CN1917250A - Method for making luminous device - Google Patents

Abstract

The present invention discloses a light emitting device comprising at least one layer comprising an organometallic dendrimer with a metal cation at its core.

Description

Method of manufacturing light emitting device

This application is a divisional application of the application No. 02805237.4 and the title of the invention "metal-containing dendrimers".

The present invention relates to metal-containing dendrimers and light emitting devices comprising said metal-containing dendrimers.

A wide variety of light-emitting low-molecular-weight metal complexes are known and have proven useful as light-emitting and charge-transporting materials in organic light-emitting devices, especially light-emitting diodes (LEDs), also known as optoelectronic (EL) devices. Analysis of spin statistics associated with the injection of opposite charge carriers that pair to form excitons shows that only 25% of the excitons formed in the LED are in the singlet state. Although it has been proposed that, under certain circumstances, the barrier of 25% singlet excitons can be exceeded, this is known to be far from 100%. For most organic materials, only singlet states are capable of radiative decay to produce light, while triplet states decay non-radiatively. It has recently been shown that it is possible to extract fluorescence from triplet excited states by including phosphorescent guest metal complexes in the host building block. However, mixture systems are sensitive to the concentration of the guest in the host, and only low concentrations of the guest can be used before phase separation causes aggregation and quenching.

Furthermore, currently used metal complexes have been designed to be volatile so that the layers can be deposited by thermal evaporation. Solution processing is preferred over evaporation in many applications, however, current materials do not form good thin films when deposited by solution processing. Furthermore, it would be advantageous to have a guest-host system in which a large number of guests can be used. This would be possible with dendritic materials.

According to the present invention, these problems are solved by forming certain dendrimers with the metal ions that are part of the core. Dendrimers are highly branched macromolecules in which branched dendrites (also known as dendrites) are attached to a core. The properties of dendrimers make them ideal for solution processing and enable the incorporation of metal complex chromophores, which have proven effective in light emitting devices (LEDs), into solution processing systems .

Known examples of metal-containing dendrimers fall into three categories: (i) metal ions at the center, (ii) metal ions at the periphery, and (iii) metal ions at branch points.

There are a large number of metal-containing dendrimers with metal ions as part of the branch points and coordinating groups attached to the metal ions, (see, for example, Chem. Comm. (2000) 1701 and Adv. Mater. 10 (4) ( 1998) 295). The photoluminescent properties of some of these materials in solution have been studied, but solid-state luminescent properties have generally not been demonstrated. It does not have to follow that a material that emits light in solution will also be light emitting in the solid state. Quenching in solid state concentration is frequent. In dendrimers with metal ions at the branch points, there is a high density of chromophores which makes condensation quenching especially likely. Likewise, in dendrimers with metal ions at the periphery, the metal ions in adjacent molecules will come close and again make concentration quenching a problem.

The present invention relates to dendrimers having metal ions as part of the core. When a metal ion chromophore is located on the core of a molecule, it will be relatively separated from the core chromophores of adjacent molecules. This will minimize possible condensation quenching or triplet-triplet extinction.

Furthermore, the organometallic dendrimers that have been disclosed generally do not have conjugated dendrons and are therefore unlikely to function properly in electroluminescent devices. For example, the only lanthanide (Ln) dendrimers reported to date have an Ln core and benzyl ether Frechet-type dendrites. These compounds have been shown to give PL emission, but have not been demonstrated in EL devices. [Kawa, M.; Frechet, J.M.J. Thin Solid Films, 331 (1998) 259].

Certain organic dendrimers have been shown to work in organic light-emitting devices. However, the use of metal ion chromophores in dendrimers expands the range of materials that can be used and will provide benefits in terms of stability and/or charge transport compared to organic systems. Of particular interest is the potential for highly efficient solution-processed phosphorescent systems. Accordingly, the present invention provides a light-emitting device comprising a layer comprising a metal ion-containing dendrimer, in particular an organometallic dendrimer having a metal cation as part of its core, said core ( or center) does not contain magnesium chelated porphyrin.

The invention relates in particular to the use of dendrimers comprising one or more at least partially conjugated organic dendrons, wherein the dendrimers have metal ions as part of the core. Dendrimers as described above form a further aspect of the invention. The atoms or groups conjugated/attached to the metal typically form part of the core itself, eg fac-tris(2-phenylpyridyl)iridium III. Thus, dendrimers generally have the formula (I):

Core-[Dendrite] _n (I)

Wherein, the core (CORE) represents a metal ion or a group comprising a metal ion, n represents an integer of 1 or greater, each dendrite (DENDRITE) may be the same or different and represents an inherently at least partially conjugated dendritic structure, The structure contains aryl and/or heteroaryl or nitrogen and optionally vinyl or ethynyl through sp ² or sp hybridized carbon atoms of said (hetero)aryl, vinyl and ethynyl or through N and (hetero)aryl with a single bond; the core is at the end of the single bond (CORE terminating in the single bond) that is attached to the sp ² hybrid (ring) of the first (hetero)aryl To or attached to a carbon atom to which is attached more than one at least partially conjugated dendritic branch; said ring carbon or nitrogen atom forming part of said dendrite. It should be understood that the terms "metal ion" or "metal cation" as used herein describe the charge state (oxidation state) that a metal would have in the absence of any attached ligand. In dendrimers comprising metal cations, the overall charge of the dendrimers is neutral and depending on the metal and the ligands involved, the metal-ligand bond will have a more or less covalent character.

When the term ethynyl as used herein refers to a divalent ethynyl group, vinyl refers to a divalent or trivalent vinyl group, and aryl refers to a divalent, trivalent or multivalent aryl group group. In preferred embodiments, the dendrites are conjugated.

Preferably, the dendrimers of the invention are luminescent in the solid state. The light emitting portion may be partly or fully within the core itself. Luminescence preferably originates from the metal complex.

Suitable branch points include aryl and heteroaryl groups, which may be fused, aromatic ring systems, and N. Connections between branch points include bonding, such as aryl-aryl, aryl-vinyl-aryl, aryl-ethynyl-aryl, aryl-aryl'-aryl (wherein aryl' may be different from aryl), N-aryl and N-aryl'-N. Individual dendrites may contain one or more branch points of each type. Additionally, in the case of intradendron aryl-vinyl-aryl and aryl-ethynyl-aryl linkages, there may be one or more aryl-vinyl or aryl-ethynyl groups between branch points connect. In practice, there may be more than one vinyl or ethynyl or aryl moiety between two aryl groups, but preferably no more than three. Furthermore, it would be advantageous to utilize asymmetric dendrimers, ie, where the dendrites are not all identical.

Thus, the dendrimers may be those of formula (II):

Core-[Dendrite ¹ ] _n [Dendrite ² ] _m (II)

wherein the core represents a metal ion or a group comprising a metal ion, n and m may be the same or different and each represent an integer of at least 1, each dendrite ¹ (which may be the same or different when n is greater than 1) and each dendrite ² (which may be the same or different when m is greater than 1) means a dendritic structure, at least one of which is fully conjugated and contains aryl and/or heteroaryl or nitrogen and optionally vinyl and/or ethynyl , which are attached via sp ² or sp hybridized carbon atoms of the (hetero)aryl, vinyl and ethynyl groups or via a single bond between N and (hetero)aryl; and the branch point in dendrite ¹ and/or the linkage between the branch points is different from that in dendrite ² ; the core is at the end of a single bond attached to the sp ² hybridized (ring) carbon atom of the first (hetero)aryl or attached to On nitrogen to which more than one conjugated dendritic branch is attached; said ring carbon atom or nitrogen forms part of said fully conjugated dendrite ¹ or dendrite ² and terminates at a single bond The core is connected to a first branch point of the other of said dendrite ¹ or dendrite ² ; at least one of the core, dendrite ¹ and dendrite ² is luminescent, and the luminescent dendrimer has the formula (III):

Core-[Dendrite] _n (III)

Wherein, the core represents a metal ion or a group comprising a metal ion, n represents an integer of 1 or greater, each dendrite may be the same or different, and represents an inherently at least partially conjugated dendritic molecular structure comprising Aryl and/or heteroaryl or N and optionally vinyl and/or ethynyl through sp ² or sp hybridized carbon atoms of said (hetero)aryl, vinyl and ethynyl or through N and a single bond connection between (hetero)aryl groups; and wherein the connections between adjacent branch points in the dendrite are not all the same, the core at the end of a single bond connected to the first (hetero)aryl ) on the sp ² hybridized (ring) carbon atom of the aryl group or on the N to which more than one dendritic branch is attached; the ring carbon atom or N forms part of the dendrite, the core and/or Or dendrites are luminous. In one aspect of the invention, the dendrites, Dendrite ¹ and/or Dendrite ² do not include N as a branch point, and are conjugated.

It should be understood that in Formulas I, II, and III, the core does not contain magnesium chelated porphyrin.

In this application, the conjugated dendrites (dendrites) are shown to consist of alternating double and single bonds away from the surface groups. However, this does not mean that the π system is completely delocalized. The delocalization of the π system depends on the regiochemistry of the linkage. In a conjugated dendron, any branch nitrogen will be attached to three aryl groups.

Dendrimers may have more than one light-emitting portion. In a preferred embodiment, the dendrimer comprises at least two intrinsically luminescent moieties, said moieties may be conjugated to each other or non-conjugated, wherein the dendrite comprises at least one said luminescent moiety. Preferably, one or more light-emitting moieties remote from the core of the dendrimer have a greater HOMO-LUMO than one or more light-emitting moieties close to the core of the dendrimer or partially or entirely within the core of the dendrimer. energy domain. In another embodiment, although the surface groups may alter the HOMO-LUMO energy domains of the chromophores on the dendrite surface, the HOMO-LUMO energy domains are substantially the same. Sometimes, in second generation dendrimers, the surface group will place the chromophore at the far end of the dendrite at a lower HOMO-LUMO energy than the next chromophore within it.

Using a UV-Vis spectrophotometer, by methods known per se, it is possible to measure the corresponding HOMO-LUMO energy domains of the respective fractions. One of the luminescent moieties may be the core itself, or be partly or fully within the core, so it is preferred that this luminescent moiety will have a smaller intrinsic HOMO- LUMO bandgap energy. Alternatively, in addition, each dendrite may itself contain more than one light-emitting moiety, in which case those light-emitting moieties further away from the core will again preferably have a larger intrinsic HOMO-LUMO bandgap than those closer to the core energy. In this case, the core itself need not be luminescent, but generally luminescent cores are preferred.

Suitable surface groups for the dendrimers include branched and unbranched alkyl groups, especially t-butyl, branched and unbranched alkoxy groups such as 2-ethylhexyloxy, hydroxy , Alkylsilane, Carboxyl, Carbocarboxylate and Vinyl. More extensive examples include: further reactable alkenes, (meth)acrylates, sulfur- or silicon-containing groups; sulfonyl groups; polyether groups; C ₁ -C ₁₅ alkyl groups (preferably tert-butyl ) group; amine group; mono-, di- or tri-C ₁ -C ₁₅ alkylamine group; -COOR group, wherein R is hydrogen or C ₁ -C ₁₅ alkyl; -OR group, formula R is hydrogen, aryl, or C ₁ -C ₁₅ alkyl or alkenyl; -O ₂ SR group, where R is C ₁ -C ₁₅ alkyl or alkenyl, or -SR group, In the formula, R is an aryl group or a C ₁ -C ₁₅ alkyl or alkenyl group; -SiR ₃ group, wherein the R groups can be the same or different and are hydrogen, a C ₁ -C ₁₅ alkyl or alkenyl group, or -SR' group (R' is aryl or C ₁ -C ₁₅ alkyl or alkenyl), aryl, or heteroaryl. Typically t-butyl and alkoxy are used. Different surface groups may be present on different dendrons or on different end groups of dendrons. Preferably, the dendrimer is solution processable, ie the surface groups render the dendrimer soluble in a solvent.

The choice of surface groups enables the dendrimers to be photopatterned. For example, there are crosslinkable groups that are capable of crosslinking upon irradiation or by chemical reaction. Alternatively, the surface groups contain removable protecting groups to leave crosslinkable groups. Typically, the surface groups are chosen such that the dendrimers are soluble in solvents suitable for solution processing.

Typically, the aryl groups within the dendron are benzene, naphthalene, biphenyl (in either case the aryl is present in the linkage between adjacent branch points) anthracene, fluorene, pyridine, oxadiazole, triazole, Triazines, thiophenes and appropriately substituted variants thereof. Generally, these groups may be optionally substituted with C ₁ -C ₁₅ alkyl or alkoxy. The aryl group at the branch point is preferably a benzene ring (which is preferably coupled at the 1, 3 and 5 positions of the ring), a pyridyl or a triazinyl ring. The dendrites themselves may contain fluorescent chromophores.

The electron affinity of dendrimers can be controlled by adding electron-withdrawing groups to the chromophore, suitable for example cyano and sulfone, which are strong electron-withdrawing groups and in the spectral region of our interest are optically clear. This and other more detailed information on dendrimers can be found in WO 99/21935, which is hereby incorporated by reference.

It should be appreciated that one or more of the dendrites attached to the core (as long as at least one of the dendrites is a specifically conjugated dendrite) may be non-conjugated. Typically, such dendrons include ether-type aryl dendrons, for example, in which benzene rings are linked by methyleneoxy chains. In addition, it should also be appreciated that when there is more than one dendrite, these dendrites may be of the same or different generation (the generation value is determined by the number of branch point groups). Advantageously, at least one dendrite is of second or higher generation in order to provide the desired solution handling properties.

The core typically contains metal cations and attached ligands; the metal is typically in the center of the core, and the core is typically luminescent. If the core is not luminescent, one or more dendrons should contain a luminescent group.

When the core comprises a metal cation and an attached ligand, the core is usually a complex of the metal cation and one, two or more coordinating groups, wherein at least one, preferably at least two coordinating groups are linked to the dendrites. Generally, the fluorescence of the dendrimers is derived from the complexes. When the core in the above formula (I), (II) or (III) represents a group comprising a metal cation, the core is usually a complex of a metal cation and two or more coordinating groups, through a single bond , at least one and preferably two or more of said groups are attached to a dendrite, dendrite ¹ or dendrite ² moiety as defined in formula (I), (II) or (III), respectively, wherein the core at the end of these formulas.

In one aspect of the invention, the core may be represented by a complex of formula (IV):

M[X-] _q Y _r (IV)

where M is a metal cation, each [X-] can be the same or different and is a coordinating group X attached to a single bond in which the core terminates, each Y can be the same or different and is a coordinating group, and q is Integer, r is 0 or an integer, the sum of (a.q)+(b.r) is equal to the number of effective coordination sites on M, where a is the number of coordination sites on [X-], b is the number of coordination sites on Y .

A single bond in the [X-] moiety (which is the bond where the core terminates) connects to the dendrite. In dendrimers, there are preferably at least two dendrons, in which case q in formula (IV) is an integer of 2 or more. The two or more dendrons typically have a structure represented by Dendrite, Dendrite ¹ and/or Dendrite ² as defined in formulas (I)-(III) above. If present, the coordinating group Y is a neutral or charged chelating ligand that is not attached to the dendron and serves to satisfy the coordination requirements of the metal cation.

Suitable metals include:

Lanthanide metals: such as cerium, samarium, europium, terbium, dysprosium, thulium, erbium and neodymium,

d-block metals, especially those of rows 2 and 3, i.e. elements 39-48 and 72-80: e.g. iridium, platinum, rhodium, osmium, ruthenium, rhenium, scandium, chromium, manganese, iron, cobalt , nickel and copper, and

Main group metals of the periodic table: metals such as group IA, group IIA, group IIB, group IIIB, for example, lithium, beryllium, magnesium, zinc, aluminum, gallium and indium. Suitable substituents Y, especially for rhenium, include CO and halogens such as chlorine. For iridium dendrimers, the ligand moiety attached to the metal is preferably a nitrogen-containing heteroaryl, such as pyridine attached to a (hetero)aryl, where the aryl may be a fused ring system, e.g. substituted or unsubstituted Substituted phenyl or benzothiophene. It should also be noted that pyridines may also be substituted. Generally less preferred are platinum dendrimers, especially platinum dendrimers with a porphyrin core with 1-2-distyryl dendrons attached to the mesenchyme.

It should be understood that the luminescence can be fluorescent or phosphorescent, depending on the metal and coordinating group chosen.

Suitable coordinating groups for f-block metals include oxygen or nitrogen donor systems such as carboxylic acids, 1,3-diketonates, hydroxycarboxylic acids including acylphenols and imidoacyl groups. husband base. It is known that luminescent lanthanide metal complexes require a photoactive group with a higher excited triplet state than the first excited state of the metal ion. The emission comes from the f-f transition of the metal, therefore, the emission color is determined by the chosen metal. A sharp emission is usually narrow and will result in a pure color emission useful for display applications. Potential device efficiencies will be higher than fluorescent systems due to the ability to harvest triplet excitons, ie phosphorescence.

Main group metal complexes exhibit ligand-based or charge-transfer emission.

The emission color is determined by the choice of ligand and metal. A wide variety of light emitting low molecular weight metal complexes are known and have been demonstrated in organic light emitting devices [see for example Macromol.Sym.125 (1997) 1-48, US-A5,150,006, US-A6, 083,634 and US-A 5,432,014]. Suitable ligands for divalent or trivalent metals are shown in Figure 1: they include for example oxinoids (I) with oxygen-nitrogen or oxygen-oxygen donor atoms, which are usually ring nitrogen atoms with substituted oxygen atoms, Or a substituted nitrogen atom or oxygen atom with a substituted oxygen atom, such as 8-hydroxyquinolinate (IA) and hydroxyquinoxalinol (hydroxyquinoxalinol) (IB), 10-hydroxybenzoquinolinate (quinolinato) (II) , indole (III), Schiff base (V), azoindole (IV), chromone derivatives (VI), 3-hydroxyflavone (VII), and carboxylic acids such as salicylate (VIII), amino Carboxylate (IX) and ester carboxylate (X). Substituents including the R and X groups are typically halogen, alkyl, alkoxy, haloalkyl, cyano, amino, amido, sulfonyl, carbonyl, aryl or heteroaryl on (hetero)aryl rings base, which can change the emission color. The R groups in formulas V and X are typically alkyl or aryl. The alkyl group is usually an alkyl group of 1 to 6 carbon atoms, especially an alkyl group of 1 to 4 carbon atoms, such as methyl, ethyl, propyl and butyl. Aryl is typically phenyl.

d-block metals form organometallic complexes with carbon or nitrogen donors such as porphyrin, 2-phenyl-pyridine, 2-thienylpyridine, benzoquinoline, 2-phenylbenzoxazole , 2-phenylbenzothiazole or 2-pyridylthiane and iminobenzene. For example, (hetero)aromatic rings may be substituted for the R and X groups given above. Emission from the d-block complexes can be ligand-based or due to charge transfer. For heavy d-block elements, strong spin-orbit coupling allows rapid intersystem transitions and emission from triplet states (phosphorescence).

In fluorescent electroluminescent devices, many excitons are formed in non-emitting triplet states, which will reduce the luminous efficiency.

Thus, devices based on phosphorescent emitters capable of harvesting triplet excitons have a much higher potential for efficiency than devices based on fluorescent emitters.

Trees can be built in a convergent or divergent approach, but a convergent path is preferred. Thus, dendrites are attached to appropriate ligands, which are subsequently attached to metal cations, thereby forming dendritic metal complexes. Subsequently, further non-dendritic ligands can optionally also be attached to the complex. Alternatively, ligands with appropriate reactive functional groups can be conjugated to metal ions and then reacted with appropriately functionalized dendrons. In the latter approach, not all ligands must have reactive functional groups, thus, this approach allows the attachment of dendrons to some but not all ligands that complex to the metal. The main property of dendrons is to impart solution processability to metal complexes and thus enable the formation of high-quality thin films suitable for light-emitting diodes.

As noted above, the dendritic metal complexes may be homoleptic or comprise more than one dendritic ligand. Alternatively, the metal complex may comprise one or preferably more than one such as 2 or 3 dendritic ligands plus one or more non-dendritic ligands. For example, a terbium complex may have three dendritic ligand terminations in the carboxylate moiety for complexing to the metal plus one or more co-ligands to satisfy the coordination sphere for the metal cation. Suitable neutral coligands include: 1,10-phenanthroline, bathophenanthroline, 2,2'-bispyridyl, benzophenone, pyridine N-oxide and derivatives of these. In addition, for iridium, it is also possible to have two dendritic phenylpyridine ligands and a third non-dendritic phenylpyridine ligand. Desirably, the amount of dendritic ligand is sufficient to provide the desired solution processing. In the case where all ligands are different dendritic metal complexes, the preparative process may yield a statistical mixture of all kinds of complexes. This is of course not detrimental provided the optical, electronic, and processing properties are satisfactory. In the case of mixed dendritic complexes, it is preferred that the moieties forming the attachment point with the metal are all the same or have similar binding constants. In the case of dendritic complexes comprising two or more distinct dendrites, it is desirable that at least one should be a conjugated dendrite. Conjugated dendrites can be composed of many different types of branch points.

The surface groups and dendrites can be altered so that the dendrimers are soluble in solvents such as toluene, THF, water and alcoholic solvents such as methanol, suitable for the chosen solution processing technique. Typically t-butyl and alkoxy are used. Furthermore, the choice of dendrons and/or surface groups may allow the formation of hybrids with dendrimers (organic or organometallic), polymers or molecular compounds. In one embodiment of the invention there is a mixture of phosphorescent dendrimers with organometallic cores and dendrimers with the same dendrite type but different cores.

According to another aspect of the invention, organometallic dendrimers can be incorporated into light emitting devices as a homogeneous layer or as a mixture with another dendrimer (organic or organometallic), polymer or molecular compound. In one embodiment, we show a first example where we realize that d-zone phosphors can be used as a uniform light-emitting layer in LEDs. Additionally, we also found that when phosphorescent organometallic dendrimers are mixed with fluorescent hosts, the emission spectrum may depend on the driving frequency at which electrical pulses occur. The device can be driven by applying a voltage (or current) pulse with a certain duration and period (together described as the drive frequency). Within timescales where the duration and/or period of the pulses are of a similar order of magnitude to the phosphorescent decay lifetime, the emission spectrum is sensitive to the driving frequency. In another embodiment, it has been found that it is advantageous to mix dendrimers with charge transport materials.

In particular, it has been found that the presence of hole-transfer materials and/or bipolar materials and/or electron-transfer materials is advantageous. In a further embodiment, the bipolar material should comprise carbazole units. Another embodiment has one or more of each charge transport material.

Organometallic dendrimers can be incorporated into LEDs in a conventional manner. In its simplest form, an organic light-emitting or electroluminescent device can be formed from a light-emitting layer sandwiched between two electrodes, at least one of which must be transparent to the emitted light. The device described above may have a conventional configuration including a transparent substrate layer, a transparent electrode layer, a light-emitting layer and a back electrode. For this purpose, standard materials can be used. Thus, in general, the transparent substrate layer is usually composed of glass, but other transparent materials such as PET may also be used.

The anode (which is usually transparent) is preferably made of indium tin oxide (ITO); but other similar materials including indium oxide/tin oxide, tin oxide/antimony, zinc oxide/aluminum, gold and platinum can also be used. Conductive polymers such as PANI (polyaniline) or PEDOT can also be used.

The cathode is usually composed of a low work function metal or alloy such as Al, Ca, Mg, Li, or MgAl, or optionally with an additional layer of LiF. Other layers are also known, including hole transport materials and/or electron transport materials. When the dendrimer is a phosphorescent emitter, it has been found to be particularly beneficial to have a hole blocking/electron transport layer between the luminescent dendrimer layer and the cathode. In an alternative configuration, the substrate may be an opaque material such as silicon, and light is emitted through the counter electrode.

An advantage of the present invention is that the layer comprising dendrimers can be deposited from solution. Dendrimer layers can be deposited using conventional solution processing techniques such as spin coating, printing, and dip coating. In a typical setup, a dendrimer-containing solution is applied to the transparent electrode layer, the solvent is evaporated, and subsequent layers are coated. The film thickness is usually 10-1000 nm, preferably less than 200 nm, more preferably 30-120 nm.

Below, with reference to accompanying drawing, utilize embodiment to describe the present invention, wherein:

Fig. 1 shows the coordination group of divalent or trivalent metal;

Figure 2 shows the structure of first generation lanthanide dendrimers;

Figure 3 shows a reaction scheme for the synthesis of the first generation 1-arylpyridine ligand;

Figure 4 shows a reaction scheme for the synthesis of three [2-(argon) pyridine] iridium (III) complexes;

Figure 5 shows the structure of the Fac tris[2-(4'-Gl-phenyl)pyridine]iridium(III) complex;

Figure 6 shows the structure of the Fac tris[2-(3'-Gl-phenyl)pyridine]iridium(III) complex;

Figure 7 shows the structure of a Pt G1-porphyrin dendrimer;

Figure 8 shows the structure of a Pt G2-porphyrin dendrimer;

Figure 9 shows the structures of Dendrimers A and Dendrimer B;

Figure 10 shows the film absorption spectra of pure dendrimer films (A, B and 12);

Figure 11 shows the luminescence of dendrimer A and B films doped with guest dendrimer 12 in EL and PL, a) mixture A: 12, PL excited at 320 nm (...), excited at 420 nm PL(°) and EL(-), b) Mixture B: 12, PL(...) excited at 320nm, PL(°) and EL(-) excited at 420nm;

Figure 12 shows the EL spectra of host (B), guest (10) and mixture under different operating conditions. Pure host emission (a), pure guest emission (b), 200nm mixture device pulse state (c), 200nm mixture device steady state (d), 150nm mixture device steady state (e);

Figure 13 shows the EL spectra of dendrimers 10 and 11;

FIG. 14 shows the PL spectrum of 12 compared to the EL spectrum of dendrimer 13 .

Figure 15 shows a reaction scheme for the synthesis of (GlPPy) _2btpIr (III) dendrimers.

Figure 16 shows a reaction scheme for the synthesis of tricarbonyl-chloro-{3,5-[4'-(2"-ethylhexyloxy)phenyl]phenyl}phenanthroline rhenium.

Figure 17 shows a reaction scheme for the synthesis of second-generation 2-arylpyridine ligands;

Figure 18 shows a reaction scheme for the synthesis of tris(4-{3",6"-[4''-(2""-ethylhexyloxy)phenyl]carbaxolyl}phenyl)amine.

Figure 19 shows the reaction scheme for the synthesis of blue light emitting Ir dendrimers in Example 26.

Comparative example 1

G0-Br(R1)

4-(2′-Ethylhexyloxy)phenyl bromide

Sodium hydride (60% dispersion in oil, 17.4 g, 435 mmol) was added in portions to a cold (ice bath) solution of 4-bromophenol (49.0 g, 283 mmol) in anhydrous DMF (780 cm ³ ). The mixture was stirred at the temperature for 2 hours and the ice bath was removed. A solution of 2-ethylhexyl bromide (54.4 cm ³ , 306 mmol) in 150 cm ³ dry DMF was added dropwise to the reaction mixture via addition funnel, and the reaction was stirred overnight (21 hours) at room temperature. The resulting mixture was diluted with water (400cm ³ ) and diethyl ether (500cm ³ ). The two phases were separated. The aqueous layer was extracted with ether (3 x 300 cm ³ ), and the organic portion and ether extracts were dried over anhydrous MgSO4, filtered and the filtrate collected and evaporated under reduced pressure to leave a yellow oil. Column chromatography on silica gel (half each time) with petroleum ether as eluent gave R1 (54.1 g, 67%), a colorless oil;

λ _max (CH ₂ Cl ₂ )/nm 284(ε/dm ³ mol ^-1 cm ^-1 1251), and 291sh(1001); δ _H (400MHz; CDCl ₃ ) 0.83-0.97(6H, m, Me), 1.30-1.57 (8H, m, _CH2 ), 1.68-1.79 (1H, m, CH), 3.78-3.84 (2H, m, _ArOCH2 ), 6.74-6.80 (2H, m, ArH), and 7.33-7.40 (2H, m, ArH); _δC (100MHz; CDCl ₃ ) 11.1, 14.1, 23.0, 23.8, 29.1, 30.4, 39.3, 70.7, 112.4, 116.3, 132.1, and 158.5. (and: and)

Comparative example 2

G0-SnBu ₃ (R2)

1-(2′-Ethylhexyloxy)-4-(tri-n-butyl)stannylbenzene

Under argon atmosphere, tert-butyllithium (1.7M, 21.7cm ³ , ^36.8mmol ) was slowly added to a cold (dry ice/ acetone bath) solution. The mixture was stirred at -78 °C for 2 hours, and tri-n-butyltin chloride (10 cm ³ , 36.8 mmol) was added dropwise to the mixture over 5 minutes, before being removed from the dry ice/acetone bath, at - It was stirred at 78°C for 1 hour. The mixture was stirred at room temperature for an additional ³ h before being quenched with 10% _NH4Cl (aq) (20 cm3). The aqueous layer was separated and extracted with DCM (2 x 10 cm ³ ). The dichloromethane (DCM) extracts and ether fractions were then dried ( _MgSO4 ) and filtered. Solvent was completely removed. Kugolrohr distilled off excess tri-n-butyltin chloride, leaving 12.0 g (99%) of R2, a pale yellow oil;

λ _max (CH ₂ Cl ₂ )/nm 277(ε/dm ³ mol ^-1 cm ^-1 826), and 284sh(660); δ _H (200MHz; CDCl ₃ ) 0.81-1.09(15H, m, Me), 1.21-1.81 (27H, m, CH ₂ & CH), 3.84 (2H, m, ArOCH ₂ ), 6.91 (2H, m, ArH), and 7.36 (2H, m, ArH).

Comparative example 3

G1-CHO(R3)

3,5-bis[4′-(2″-ethylhexyloxy)phenyl]benzaldehyde

method 1:

Under argon atmosphere, R2 (8.50g, 17.2mmol), 3,5-bis-bromobenzaldehyde (1.18g, 4.47mmol), CuI (790mg, 4.15mmol), tetrakis (triphenylphosphine) palladium (0 ) (790 mg, 0.684 mmol) and 20 cm ³ of distilled triethylamine were heated at reflux for 14 hours. The reaction mixture was cooled and filtered through a silica gel plug using DCM as eluent. The filtrate was collected and the solvent was completely removed to give a tan oil. The residue was purified by column chromatography on silica using ethyl acetate-petroleum ether (0:1-1:10) as eluent to afford R3, a colorless oil (1.91 g, 83 %).

ν _max /cm ^-1 (pure) 1700 (C=O); λ _max (CH ₂ Cl ₂ )/nm 247 (ε/dm ³ mol ^-1 cm ^-1 22406), 274 (27554), and 339sh (1817 ); δ _H (400MHz; CDCl ₃ ) 0.88-1.01 (12H, m, Me), 1.30-1.61 (16H, m, CH ₂ ), 1.73-1.84 (2H, m, CH), 3.94 (4H, m, ArOCH ₂ ), 7.04 (4H, m, ArH), 7.62 (4H, m, ArH), 7.99 (3H, s, ArH), and 10.13 (1H, s, CHO); δ _C (100MHz; CDCl ₃ ) 11.1 , 14.1, 23.1, 23.9, 29.1, 30.5, 39.4, 70.6, 115.0, 126.0, 128.2, 130.8, 131.9, 137.4, 142.3, 159.6, and 192.5; m/z[CI(NH ₃ )]533(MNH ₄ ⁺ ) , and515(M ⁺ ).

Method 2:

p -4B (213mg, 0.851mmol), 3,5-di-bromobenzaldehyde (98mg, 0.370mmol), tetrakis(triphenylphosphine)palladium(0) (30mg, 0.026mmol), 2M Na ₂ CO ₃ (aqueous ) (0.5 cm ³ ), EtOH (0.5 cm ³ ) and toluene (1.1 cm ³ ) were degassed and heated at reflux (bath temperature 96° C.) under argon atmosphere for 18 hours. Allow the mixture to cool. Water (4cm ³ ) and diethyl ether (5cm ³ ) were added to the mixture. The two phases were separated. The aqueous layer was extracted with diethyl ether (3 x 5 cm ³ ). The organic layer and ether extract were combined, dried over anhydrous magnesium sulfate, and filtered. Solvent was completely removed. The residue was purified by column chromatography on silica gel using petroleum ether (60-80° C.) as eluent to afford R3 (172 mg, 90%) as a colorless oil.

Comparative example 4

G0-B(X) ₂

4-(2′-Ethylhexyloxy)phenylboronic acid

Under argon atmosphere, tert-butyllithium (1.7M, ^66.0cm3 , 112mmol) was carefully added to a cold (dry ice/acetone bath) of G0-BrR1 (20.0g, 70.1mmol) in ^300cm3 of anhydrous THF. in solution. The mixture was stirred at -78°C for 1 hour, then trimethyl borate (57.2 cm ³ , 421 mmol) was slowly added to the cold mixture. The reaction was stirred at -78°C for 2 hours before being removed from the dry ice/acetone bath. The mixture was stirred at room temperature for an additional 2.5 hours before being quenched with 3M HCl(aq) (30 cm ³ ). The two layers were separated. The aqueous layer was extracted with DCM (3 x 30 cm ³ ). The organic layer and DCM extract were combined and dried over anhydrous magnesium sulfate, then filtered and the solvent was completely removed. Purification by column chromatography on silica gel using ethyl acetate-petroleum ether (1:10) followed by ethyl acetate-DCM (0:1-1:3) as eluent gave the two main Bands; less polar compound 4A (6.44 g), a colorless oil; δ _H (200 MHz; CDCl ₃ ) 0.81-1.05 (6H, m, Me), 1.22-1.62 (8H, m, CH ₂ ), 1.68-1.88 (1H, m, CH), 3.91 (2H, m, ArOCH ₂ ), 6.98 (2H, m, ArH), and 7.77 (2H, m, ArH); and more moles of compound 1 trimerized Body 4B (8.40 g), a colorless oil; δ _H (200 MHz; CDCl ₃ ) 0.85-1.07 (6H, m, Me), 1.30-1.64 (8H, m, CH ₂ ), 1.70-1.90 (1H, m, CH), 3.95 (2H, m, _ArOCH2 ), 7.03 (2H, m, ArH), and 8.18 (2H, m, ArH).

NOTE: Either compound 4A or 4B can be used in the reaction to form the next generation of dendrites. In the case of 4A or 4B as a dimer, the number of protons in ¹ HNMR is considered a ratio.

Comparative example 5

G1-Br(R5)

3,5-bis[4′-(2″-ethylhexyloxy)phenyl]phenyl bromide

p-boronic acid 4B (7.90g, 31.6mmol), 1,3,5-tribromobenzene (4.53g, 14.4mmol), tetrakis(triphenylphosphine)palladium(0) (1.16g, 1.00mmol), 2M _Na2 A mixture of CO ₃ (aq) (15 cm ³ ), EtOH (15 cm ³ ) and toluene (43 cm ³ ) was degassed and heated at reflux (bath temperature 101° C.) under argon atmosphere for 22 hours. Allow the mixture to cool. Water (20cm ³ ) and diethyl ether (30cm ³ ) were added to the mixture. The two phases were separated. The aqueous layer was extracted with diethyl ether (3 x 20 cm ³ ). The organic layer and ether extract were combined, dried over anhydrous magnesium sulfate, and filtered. Solvent was completely removed. The residue was purified by column chromatography on silica gel using petroleum ether (60-80 °C) as eluent to afford R5 (6.04 g, 74%) as a colorless oil;

δ _H (200MHz; CDCl ₃ ) 0.82-1.02 (12H, m, Me), 1.26-1.60 (16H, m, CH ₂ ), 1.70-1.83 (2H, m, 2xCH), 3.90 (4H, m, ArOCH ₂ ), 6.99(4H, m, ArH), 7.54(4H, m, ArH), and 7.62(3H, s, ArH); m/z[MALDI]566(M ⁺ ).

Additionally, 910 mg (9%) of the tri-substituted compound was isolated as a colorless oil;

δ _H (200MHz; CDCl ₃ ) 0.82-1.02 (18H, m, Me), 1.25-1.63 (24H, m, CH ₂ ), 1.70-1.83 (3H, m, CH), 3.90 (6H, m, ArOCH ₂ ), 7.01(6H, m, ArH), 7.62(6H, m, ArH), and7.65(3H, s, ArH); m/z[APCI ⁺ ]692(MH ⁺ ).

Comparative example 6

G1-BX ₂ (R6)

To a cold (dry ice/acetone bath) solution of aryl bromide R5 (1.82 g, 3.22 mmol) in 18 ^cm anhydrous THF was added tert-butyl lithium (1.7M, 3.0 cm ³ , 5.15 mmol) under argon atmosphere middle. The reaction mixture was stirred at -78°C for 1 hour and its color became dark reddish brown. Tri-n-butyl borate (5.2 cm ³ , 19.3 mmol) was slowly added to the mixture and the reaction was stirred at -78°C for 1 hour before removing from the dry ice/acetone bath. The mixture was stirred at room temperature for an additional 3.5 hours before being quenched with 3M HCl(aq) (7 cm ³ ). The two layers were separated. The aqueous layer was extracted with DCM (3 x 5 cm ³ ). The organic layer and DCM extracts were dried over anhydrous magnesium sulfate and filtered. Solvent was completely removed. Purification on a silica gel column using ethyl acetate-petroleum ether (1:10) and then ethyl acetate-DCM (1:4) as eluent afforded 1.63 g (96%) of R6, a free color oil. However, the structure of R6, which can be used to form higher generation dendrites with excellent yield, has not been fully determined.

Comparative Example 7-[G-3] ₃ N (Compound A in Figure 9)

Potassium tert-butoxide (122mg, 1.09mmol) was added to [G-3]phosphonate (Comparative Example 7A, 551mg, 0.218mmol) and Comparative Example 8 (34.6mg, 0.054mmol) in anhydrous THF (15ml) solution and heated at reflux under argon for about 21.5 hours, then the solvent was removed. Dichloromethane (50ml) was added and the organic layer was washed with water (50ml) and brine (50ml), dried over anhydrous sodium sulfate, filtered and the solvent was removed to leave a yellow solid. The residue was difficult to purify by column chromatography on silica. A small amount of pure material (about 90 mg) could be isolated when a dichloromethane/petroleum ether mixture (1.5:3.5-2:3) was used as eluent. The remaining impure material (about 260mg) and iodine (17mg, 0.07mmol) were dissolved in toluene (6ml) and heated at reflux for 5.2 hours. The solvent was removed and the residue was purified by column chromatography on silica using a dichloromethane/petroleum ether mixture (1.5:3.5 to 2:3) as eluent. The main fractions were collected and the solvent was removed. The residue was mixed with the first fraction of pure material to afford 21 (268 mg, 63%), mp 266-267°C. Anal. Calcd. for _C594H687N : C, 91.0; _H , 8.8; N, 0.2. Measured C, 90.6; H, 9.3; N, 0.

ν _max (KBr disk)/cm ^-1 : 958 (C=CH trans).λ _max (CH ₂ Cl ₂ )/nm: 239 (logε/dm ³ mol ^-1 cm ^-1 5.52), 323 (6.08) , 334sh (6.04) and 424 (5.16). δ _H (400MHz; CDCl ₃ ): 1.40 (432H, s, t-Bu), 7.03-7.37 (96H, cv H, G-1 vinyl H, G-2 vinyl H and G-3 vinyl H), 7.17 and 7.50 (12H, AA'BB', cp H), 7.39 (24H, dd, J=1.5, sp H), 7.45 (48H, d, J=1.5, sp H ), 7.59 and 7.63 (12H, AA'BB', cp H), 7.65-7.77 (63H, bp H). m/z (MALDI): 7839.4 (M ⁺ , 100%). GPC: M _w =1.0× 10 ⁴ and M _n =8.8×10 ³ . (vinyl: vinyl)

Example 1

G1-COOH(1)

3,5-bis[4′-(2″-ethylhexyloxy)phenyl]benzoic acid

Dichloromethane (DCM) (0.8cm ³ ), the aldehyde (3,5-bis[4′-(2″-ethylhexyloxy)phenyl]benzaldehyde) of comparative example 3 (515mg, 1.00mmol) A solution in 5 ^cm DCM and tetra-n-butylammonium bromide (64 mg, 0.200 mmol) were added sequentially to a ^cold ( _ice bath) mixture. The mixture was stirred at 0-2°C for 30 minutes and then at room temperature for 16 hours before quenching with acetic acid (31 drops). Using DCM followed by ethyl acetate as eluent, the The mixture was passed through a small plug of hypoacetylide. The filtrate was collected and the solvent was completely removed. Column chromatography on silica gel using ethyl acetate-DCM-acetic acid (0:1:0 to 1:4:0.01) as eluent The crude residue was purified to give 458 mg (86%) of 1, a pale yellow solid; mp 105° C.; (measured: C, 79.2; H, 8.7. Calcd. for C ₃₅ H ₄₆ O ₄ C , 79.2; H, 8.7%);

ν _{max / cm} ^{-1 (} pure ⁾ ₁₆₈₇ (C=O) ^; ); δ _H (400MHz; CDCl ₃ ) 0.90-1.03 (12H, m, Me), 1.35-1.63 (16H, m, CH ₂ ), 1.77-1.86 (2H, m, CH), 3.93 (4H, m, ArOCH ₂ ), 7.04 (4H, m, ArH), 7.63 (4H, m, ArH), 7.98 (1H, s, ArH), and 8.27 (2H, brs, ArH), ( _COOH not obser); 100MHz; CDCl ₃ ) 11.1, 14.1, 23.1, 23.9, 29.1, 30.5, 39.4, 70.6, 93.2, 114.9, 126.6, 128.2, 130.3, 132.2, 141.8, 159.4, and 185.6; m/z[CI(NH ₃ )] 549(MNH ₄₊ ), ^and 531(M ⁺ ).

Example 2

G1-COO-Eu(2)

Europium 3,5-bis[4′-(2″-ethylhexyloxy)phenyl]benzoate

Under reduced pressure (water aspirator), to G1-COOH (1) (500 mg, 0.942 mmol), freshly dried Eu(OAc) ₃ ·3H ₂ 0 (70°C, 0.5 mbar, overnight) (103 mg, 0.314 mmol) and 28cm of ^{chlorobenzene} was heated (bath temperature 70-75°C). The solvent was removed slowly over 1.5 hours and the residue was evaporated in vacuo to leave a light yellow oil. It was then triturated with MeOH to give a pale yellow solid. The solid was then dried under vacuum (0.5 mbar, overnight) to yield 552 mg (100%) of europium complex 2 as a pale yellow solid; (measured: C, 71.7; H, 7.9. For C ₁₀₅ H ₁₃₅ EuO ₁₂ Calculated for _: C, 72.4; H, 7.8%; calculated for _{C105H137EuO13} , C, 71.7; H, 7.9% ₎ ; _λmax /nm (thin film) 268 and 328.

Example 3

G1-COO-Tb (3)

Terbium 3,5-bis[4′-(2″-ethylhexyloxy)phenyl]benzoate

Under reduced pressure (water aspirator), to G1-COOH (1) (500 mg, 0.942 mmol), freshly dried Tb(OAc) ₃ ·3H ₂ O (70°C, 0.5 mbar, overnight) (105 mg, 0.314 mmol) and 28 cm of ^{chlorobenzene} was heated (bath temperature 70-75 ° C). Most of the solvent was slowly removed over 1.5 hours and the residue was dried under vacuum to leave a light yellow oil. The oil was then triturated with MeOH to give a pale yellow solid. The solid was then dried under vacuum (0.5 mbar, overnight) to yield 548 mg (100%) of the desired terbium complex 3 as a pale yellow solid; (measured values: C, 71.9; H, 7.6. For C ₁₀₅ H Calculated _for135TbO12 : C, 72.1; H, 7.8%; calculated for _{C105H137TbO13} , C, 71.4 _; H, 7.8%); _{λmax /} nm (thin film) 270 _and 330.

General procedure for coordination of co-ligands with G1-COO-Ln (applicable for europium and terbium).

A mixture of europium complex 2 (6.0 mg, 0.003 mmol), 2,2'-bispyridyl (0.5 mg, 0.003 mmol, ) and 0.2 cm ³ toluene was stirred for 10 minutes to give a clear/homogeneous solution. The solution was filtered through raw cotton prior to spin coating onto the quartz substrate at 1500 rpm for 60 seconds;

G1-COO-Eu 2,2'-dipyridyl; _λmax /nm (thin film) 268 and 329;

Gl-COO-Eu 4,4'-di-tert-butyl-2,2'-dipyridyl; _λmax /nm (thin film) 268 and 327;

Gl-COO-Eu 4,4'-di-tert-butyl-2,2'-dipyridyldi-N-oxide; _λmax /nm (thin film) 267 and 323;

G1-COO-Eu·1,10-phenanthroline; _λmax /nm (thin film) 268 and 329;

G1-COO-Eu·1,10-phenanthroline N-oxide; _λmax /nm (thin film) 268 and 329;

Gl-COO-Eu·Bathocuproine; _λmax /nm (thin film) 271 and 329;

Gl-COO-Tb 4,4'-di-tert-butyl-2,2'-dipyridyl di-N-oxide;

_λmax /nm (thin film) 267 and 326;

G1-COO-Tb·1,10-phenanthroline; _λmax /nm (thin film) 270 and 326;

G1-COO-Tb 1,10-phenanthroline N-oxide; _λmax /nm (thin film) 270 and 326;

G1-COO-Tb. Bathocuproine; _λmax /nm (thin film) 270 and 329.

Example 4

2-(4'-BrPh)Py

2-(4′-Bromophenyl)pyridine

p-2-Bromopyridine (1.22g, 7.69mmol), 4-bromophenylboronic acid (2.00g, 10.0mmol), tetrakis(triphenylphosphine)palladium(0) (622mg, 0.538mmol), _{2M Na2CO3} (aq) (8cm ³ ), a mixture of EtOH (8cm ³ ) and toluene (22cm ³ ) was degassed, then heated at reflux (bath temperature 105°C) under argon atmosphere for 17h. Allow the reaction to cool. Water (10cm ³ ) and diethyl ether (10cm ³ ) were added to the mixture. The two phases were separated. The aqueous layer was extracted with diethyl ether (3 x 10 cm ³ ). The organic layer was combined with ether extracts, washed with brine (1×30 cm ³ ) and dried over anhydrous magnesium sulfate. Solvent was completely removed. The residue was purified by column chromatography on silica gel using petroleum ether (60-80° C.) to give the desired product 4 (1.52 g, 84%) as a colorless solid. Melting point 62°C; (EC Butterworth, IM Heibron and DH Hey, J.Chem.Soc., 1940, 355) δ _H (200MHz; CDCl ₃ ) 7.23-7.35 (1H, m, PyH), 7.58-7.67 (2H, m, ArH ), 7.68-7.81 (2H, m, PyH), 7.83-7.93 (2H, m, ArH), and 8.69 (1H, m, PyH). ¹ H NMR is similar to that reported in MAGutierrez, GR Newkome, J. Selbin, J Organomet. Chem., 1980, 202, 341-350.

Example 5

2-(4′-Gl-Ph)Py

2-(4′-{3″,5″-bis[4-(2″″-ethylhexyloxy)phenyl]phenyl}phenyl)pyridine

The boron compound (G1-BX ₂ ) (1.18g, 2.22mmol) of Comparative Example 6, 2-(4'-bromophenyl)pyridine (400mg, 1.71mmol), tetrakis(triphenylphosphine)palladium(0) (138 mg, 0.120 mmol), 2M Na ₂ CO ₃ (aqueous solution) (1.8 cm ³ ), a mixture of EtOH (1.8 cm ³ ) and toluene (5.0 cm ³ ) was degassed, then heated at reflux under an argon atmosphere (bath temperature 103°C) for 16h. The mixture was cooled and diluted with water (4cm ³ ) and diethyl ether (5cm ³ ). The two phases were separated. The aqueous layer was extracted with diethyl ether (3 x 10 cm ³ ). The organic layer and ether extract were combined and dried over anhydrous sodium sulfate. The solvent was completely removed to give 1.5 g of crude product. The residue was purified by column chromatography on silica gel using ethyl acetate-petroleum ether (0:1-1:10) as eluent to give 5 (1.04 g, 95%) as a white solid; (measured: C, 84.1; H, 8.3, N, _2.3 calcd for _C45H53NO3C , _84.5 ; H, 8.4, N, 2.2%);

λ _max /nm (thin film) 286; δ _H (400MHz; CDCl ₃ ) 0.89-1.03 (12H, m, Me), 1.32-1.67 (16H, m, CH ₂ ), 1.77-1.88 (2H, m, CH) , 3.93 (4H, m, ArOCH ₂ ), 7.05 (4H, m, ArH), 7.25-7.28 (1H, m, PyH), 7.66 (4H, m, ArH), 7.75-7.85 (7H, m, ArH & PyH), 8.15 (2H _, m, ArH), and 8.76 (1H _, m, PyH); 122.2, 124.3, 127.3, 127.7, 128.3, 133.4, 136.8, 138.4, 141.6, 141.8, 142.1, 149.7, 157.0, 159.2, m/z [APCI ⁺ ] 640 (M ⁺ ).

Example 6

2-(3′-BrPh)Py

2-(3′-Bromophenyl)pyridine

p-2-Bromopyridine (2.40g, 15.3mmol), 3-bromophenylboronic acid (4.00g, 19.9mmol), tetrakis(triphenylphosphine)palladium(0) (1.24g, 1.07mmol), 2M _{Na2CO 3} (aq) (16cm ³ ), a mixture of EtOH (16cm ³ ) and toluene (44cm ³ ) was degassed and heated at reflux (bath temperature 106°C) under argon atmosphere for 17h. The reaction was allowed to cool to give an orange-yellow mixture. The mixture was diluted with water (10cm ³ ) and ether (20cm ³ ). The two phases were separated. The aqueous layer was extracted with diethyl ether (3 x 15 cm ³ ). The organic layer and ether extract were combined and dried over anhydrous sodium sulfate. The solvent was completely removed to leave an orange oil. The oil was purified by column chromatography on silica gel using ethyl acetate-petroleum ether (0:1-1:10) as eluent to afford 6 (2.86 g, 80%) as a pale yellow oil. δ _H (200MHz; CDCl ₃ ) 7.18-7.40 (2H, m, PyH & ArH), 7.55 (1H, m, ArH), 7.66-7.85 (2H, m, PyH), 7.92 (1H, m, ArH), 8.17 -8.19 (1H, m, ArH), and 8.71 (1H, m, PyH). ¹ H NMR is similar to that reported in M. van der Sluis, V. Beverwijk, A. Termaten, F. Bickelhaupt, H. Kooijman, ALSpek, Organometallics, 1999, 18, 1402-11407.

Example 7

2-(3′-Gl-Ph)Py

2-(3′-{3″,5″-bis[4-(2″″-ethylhexyloxy)phenyl]phenyl}phenyl)pyridine

The boron compound of Comparative Example 6: (G1-BX ₂ ) (455mg, 0.858mmol), 2-(3′-bromophenyl)pyridine (154mg, 0.659mmol), tetrakis(triphenylphosphine)palladium(0) (54mg, 0.046mmol), 2M Na ₂ CO ₃ (aqueous solution) (0.7cm ³ ), a mixture of EtOH (0.7cm ³ ) and toluene (2.0cm ³ ) was degassed and heated under reflux under an argon atmosphere (bath temperature 103 ℃) 17h. The mixture was cooled and passed through a pad of silica gel using diethyl ether as eluent. The filtrate was collected and the solvent was completely removed to leave an orange oil. The oil was purified by column chromatography on silica gel using ethyl acetate-petroleum ether (0:1-1:10) as eluent to afford 7 (362 mg, 86%), a colorless oil. (Measured: C, 84.2; H, 8.5, N, 2.2. Calculated for C ₄₅ H ₅₃ NO ₂ C, 84.5; H, 8.4, N, 2.2%); λ _max /nm (thin film) 270; δ _H ( 400MHz; CDCl ₃ ) 0.90-1.03 (12H, m, Me), 1.32-1.67 (16H, m, CH ₂ ), 1.79-1.86 (2H, m, CH), 3.95 (4H, m, ArOCH ₂ ), 7.06 (4H, m, ArH), 7.23-7.31 (1H, m, PyH), 7.62 (1H, m, ArH), 7.68 (4H, m, ArH), 7.75-7.88 (6H, m, PyH & ArH), 8.05 (1H, m, ArH), 8.37 (1H _{, m} , ArH), and 8.77 (1H, m, PyH); , ^{70.5,114.8,120.8,122.3,124.3,124.5,126.0,128.0,128.3,129.2,133.4,136.8,140.0,141.94,141.97,142.1,149.7,157.4,159.2} , and 164.3 m (M ⁺ ).

Example 8

(2-PhPy)[2-(3'-BrPh)Py] ₂ Ir

(2-Phenylpyridine)-bis[2-(3'-bromophenyl)pyridine]iridium(III)

Before cooling, 2-(3'-bromophenyl)pyridine (367 mg, 1.57 mmol), iridium chloride trihydrate (124 mg, 0.352 mmol), H ₂ O (3.0 cm ³ ) and 2 - The mixture of ethoxyethanol (10 cm ³ ) was heated (bath temperature: 130° C.) for 23 h. A golden yellow solid precipitated from the mixture. The solid was filtered, washed with 95% EtOH ( ^20cm3 ) and dried to yield 197mg. The resulting material was passed through a silica gel column using ethyl acetate-petroleum ether (0:1-1:10), DCM then methanol as eluents. The filtrate was collected (about 600 cm ³ ) and concentrated to about 50 cm ³ . An orange-yellow solid precipitated and was collected by filtration. The filter cake was washed with MeOH (ca. 10 cm ³ ). The golden yellow solid was dried to give 177 mg;

δ _H (200MHz; CDCl ₃ ) 5.74 (2H, d, J8.4Hz, ArH), 6.70 (2H, m, ArH), 6.78-6.79 (2H, m, PyH), 7.62 (2H, d, J2.0Hz , ArH), 7.74-7.93 (4H, m, PyH), and 9.19 (2H, d, J5.8Hz, PyH); m/z [APCI ⁺ ] 659 (C ₂₂ H ₁₄ Br ₂ IrN ₂ ⁺ ).

A mixture of the iridium complex and 2-phenylpyridine (738 mg, 4.756 mmol) and silver triflate (82 mg, 0.317 mmol) was heated (bath temperature: 130-140° C.) for 4.0 days under argon atmosphere. The reaction mixture was then cooled to room temperature to give a tan precipitate. The solid was washed with ethanol (10 cm ³ ) and dried. The residue was further purified by column chromatography on silica gel using DCM as eluent to afford 100 mg (78%) of 8 as an orange-yellow solid;

λ _max (thin film)/nm 248, 297, and 389; δ _H (200MHz; CDCl ₃ ) 6.65-.98 (11H, m, ArH and/or PyH), and 7.45-7.93 (11H, m, ArH and/or or PyH); m/z [APCI ⁺ ] 814 (MH ⁺ ).

Example 9

(2-PhPy)[2-(3′-G1-Ph)Py] ₂ Ir

(2-Phenylpyridine)-bis[2-(3′-{3″,5″-bis[4-(2″″-ethylhexyloxy)phenyl]phenyl}phenyl)pyridine] iridium(III)

The boron compound (G1-BX ₂ ) (196mg, 0.369mmol) of Comparative Example 6 , 8 (100mg, 0.123mmol), tetrakis (triphenylphosphine) palladium (0) (10mg, 0.009mmol), 2MNa ₂ CO ₃ (aq) (0.3cm ³ ), a mixture of EtOH (0.3cm ³ ) and toluene (1.0cm ³ ) was degassed and heated at reflux (bath temperature 103°C) under argon atmosphere for 44h. The mixture was cooled and purified by column chromatography on silica gel using ethyl acetate-petroleum ether (1:10) and then DCM-petroleum ether (1:4) as eluents to give about 18 mg (about 9% ) of 9 , an orange solid. λ _max /nm (thin film) 279 and 390; δ _H (200MHz; CDCl ₃ ) 0.83-1.02 (24H, m, Me), 1.23-1.64 (32H, m, CH ₂ ), 1.68-1.88 (4H, m, CH), 3.90 (8H, m, ArOCH ₂ ), 6.88-7.09 (17H, m, ArH and/or PyH), 7.24-7.27 (1H, m, ArH and/or PyH), 7.57-7.75 (21H, ArH and/or PyH), and 7.89-8.03 (5H, m, ArH and/or PyH).

Example 10

Fac[2-(4′-G1-Ph)Py] ₃ Ir

Fac tris[2-(4′-{3″,5″-bis[4-(2″″-ethylhexyloxy)phenyl]phenyl}phenyl)pyridine]iridium(III)

2-(4'-G1-Ph)Py 5 (490 mg, 0.766 mmol), iridium chloride trihydrate (68 mg, 0.191 mmol), H ₂ O (1.6 cm ³ ) and 2-Ethoxyethanol (4.9cm ³ ) was heated (bath temperature: 130°C) for 28h. The resulting mixture was passed through a silica gel column using ethyl acetate-petroleum ether (0:1-1:10) followed by DCM as eluent. Solvent was completely removed. The residue was dissolved in about ² cm of DCM and about 2 ^cm of methanol was added, then the mixture was allowed to cool. The precipitate (about 238 mg) was collected and used in the next step without further purification. The mother liquor was concentrated to recycle unreacted 5 (ca. 244 mg).

Under argon atmosphere, for the iridium complex obtained above, cyclic ligand 5 (about 244 mg), 2-(4′-G1-Ph)Py 5 (200 mg, 0.313 mmol) and silver triflate (70 mg , 0.272mmol) of the mixture was heated (bath temperature 130-140°C) for 88h. The reaction mixture was then cooled to room temperature and about 5 ^cm of DCM was added. The tan mixture was purified by column chromatography on silica gel using DCM-ethyl acetate-petroleum ether (0:1:10-1:1:10) as eluent to give 200 mg (for IrCl ₃ . 10 for two steps of 3H ₂ O (49%), an orange-yellow solid; TGA _(5%) 410 °C; (measured: C, 76.8; H, 7.5, N, 2.0. C ₁₃₅ H ₁₅₆ IrN ₃ O ₆ Calculated value C, 76.9; H, 7.5, N, 2.0%);

λ _max /nm (thin film) 277, and 397; _H (200MHz; CDCl ₃ ) 0.78-1.03 (36H, m, Me), 1.15-1.50 (48H, m, CH ₂ ), 1.52-1.72 (6H, m, CH), 3.65 (12H, m, ArOCH ₂ ), 6.58 (12H, m, ArH), 6.92 (3H, t, J6.4Hz, PyH), and 7.32-7.92 (39H, m, ArH &PyH); m /z[MALDI]2105, 2106, 2107, 2108, 2109, 2110, 2111, 2112, 2113(M ⁺ ).

Example 11

Fac[2-(3′-G1-Ph)Py] ₃ Ir

Fac tris[2-(3′-{3″,5″-bis[4-(2″″-ethylhexyloxy)phenyl]phenyl}phenyl)pyridine]iridium(III)

Before cooling, 2-(3'-G1-Ph)Py 7 (294 mg, 0.459 mmol), iridium chloride trihydrate (41 mg, 0.115 mmol), H ₂ O (1.0 cm ³ ) and 2-ethoxy A mixture of ethyl alcohol (3.0 cm ³ ) was heated (bath temperature: 125-135° C.) for 39 h. The resulting mixture was passed through a silica gel column using ethyl acetate-petroleum ether (0:1-1:10), DCM then MeOH as eluents. The filtrate was collected (about 600 cm ³ ) and concentrated to about 50 cm ³ . An orange-yellow solid precipitated and was collected by filtration. The residue was washed with MeOH (ca. 10 cm ³ ). The golden yellow solid was dried (177 mg). The residue was precipitated with DCM and methanol ( ^3cm3 ) to give impure iridium complex as a yellow solid (125mg). At the same time, excess 2-(3'-G1-Ph) Py7 was collected from the mother liquor. Both products were used in the next step without further purification. A mixture of the iridium complex obtained above and recycled 2-(3'-G1-Ph)Py 7 and silver triflate (34 mg, 0.133 mmol) was heated under argon atmosphere (bath temperature: 130 °C) 3.5 days. The reaction was then cooled to room temperature. The tan mixture was purified on a silica gel column using DCM-ethyl acetate-petroleum ether (0:1:10-1:1:10) as eluent to obtain 95 mg (for the IrCl ₃ ·3H ₂ O TGA _(5%) 400 °C; (measured: C, 76.7; H , 7.2, N, 2.1. Calcd. for C ₁₃₅ H ₁₅₆ IrN ₃ O ₆ C, 76.9; H , 7.5, N, 2.0%);

λ _max /nm (thin film) 279 and 390; δ _H (400MHz; CD ₂ Cl ₂ ) 0.92-1.07 (36H, m, Me), 1.31-1.66 (48H, m, CH ₂ ), 1.73-1.86 (6H, m, CH), 3.95 (12H, m, ArOCH ₂ ), 7.00-7.13 (18H, m, ArH & PyH), 7.30 (3H, m, ArH) 7.62-7.g3 (27H, m, ArH & PyH) , 8.10 (3H _, m, ArH), and _8.15 (3H, m, PyH); 123.6, 123.8, 124.2, 129.0, 129.7, 134.0, 134.3, 137.4, 138.1, 142.5, 144.1, 145.4, 148.2, 160.0, and 167.0; m/z [MALDI] 2105, 2106, 2107, 2111, 1109, 2 , 2112, 2113 (M ⁺ ).

Example 12

G1-Pt-porphyrin

5,10,15,20-Tetrakis[3′,5′-bis(3″,5″-di-tert-butylstyryl)phenyl]porphyrinatoplatinum(II) (12)

5,10,15,20-tetrakis[3′,5′-bis(3″,5″-di-tert-butylstyryl)phenyl]porphyrin (WO99/21935: 1-porphyrin: No. I/Second Example) (50.0 mg, 21.5 mmol) was added to a refluxing solution of platinum(II) chloride (11.4 mg, 42.9 mmol) in benzonitrile (1 cm ³ ). The solution was then heated at reflux under nitrogen flow for 1 hour to remove evolved hydrogen chloride. Solvent was removed under vacuum. Next, column chromatography on silica was performed eluting with DCM-petroleum ether (1:3). The impure fractions were combined and further purified by column chromatography using DCM-petroleum ether (1:4) as eluent. The combined material was recrystallized from a DCM-MeOH mixture to afford 42.0 mg (77%) of 12 as a brick-red solid; mp > 295° C. (decomposition) (measured: C, 81.6; H, 7.9; N, 2.1. calcd for _C172H204N4Pt (C, 81.9; H, 8.2; N, 2.2 _% ); ν _max (KBr)/cm ^-1 1594 (C=C), and 959 (C= _CH trans); _max (CHCl ₃ )/nm(logε/dm ³ mol ^-1 cm ^-1 ) 309(5.43), 328sh(5.30), 413(5.64), 514(4.60), and 544(4.21); δ _H (400MHz, CDCl ₃ ) 1.35 (144H, s, t-Bu), 7.36-7.43 (40H, m, ArH & vinyl H), 8.11 (4H, br s, ArH), 8.29 (8H, d, J 1.0Hz, ArH) , and 8.97 (8H, s, b-pyrrolic H); m/z [MALDI] 2523 (MH ⁺ ) (pyrrolic: pyrrole)

Example 13

G2-Pt-porphyrin

5,10,15,20-Tetrakis[3′,5′-bis(3″,5″-bis(3,5-di-tert-butylstyryl)styryl)phenyl]porphyrin Platinum(II) root(13)

5,10,15,20-Tetrakis[3′,5′-bis(3″,5″-bis(3,5-di-tert-butylstyryl)styryl)phenyl]porphyrin (WO99/21935: 2-Porphyrin: first/second example) (50.0 mg, 10.3 mmol) was added to platinum(II) chloride (21.3 mg, 80.1 mmol) in benzonitrile (1.0 cm ³ ) The solution was refluxed, and further washed with benzonitrile (1.0cm ³ ). The mixture was then heated at reflux under nitrogen flow for 2.5 hours to remove evolved hydrogen chloride. The solvent was removed and the residue was purified by column chromatography using DCM-petroleum ether (1:4) as eluent to afford 36.8 mg (71%) of 13 , an orange solid; δ _H (200 MHz, CDCl ₃ ) 1.31 (288H, s, t-Bu), 7.18-7.65 (120H, m, vinyl H & ArH), 8.23 (4H, s, ArH), 8.34 (8H, s, ArH), and 9.05 (8H, s , b-pyrrole H).

Device manufacturing

LEDs were fabricated by the following method. A patterned indium tin oxide (ITO) substrate was cleaned with acetone and 2-propanol in an ultrasonic bath. A hole injection layer of PEDOT (Bayer) was spin-coated from water at 1000 rpm onto a clean ITO substrate and dried on a hot plate at 80° C. for 5 minutes. The dendrimer solution was then spin-coated onto the PEDOT layer at a speed of 800 rpm to obtain a film typically 100 nm thick; the aluminum cathode was then evaporated to obtain a device with an active area of ² mm. Device testing was performed under vacuum using a Keithley source measure unit operating in DC and a Hewlett Packard pulser operating in a pulsed state (settling time < 10 ns). The RC value of the device that determines the time required to charge the LED is estimated at about 100ns, and the driving conditions are chosen appropriately. Emission spectra were measured using an ISA Spectrum One CCD spectrometer. PL and PL excitation (PLE) spectra were obtained on an ISA Fluoromax fluorometer. All emission spectra are collected for instrument response. As a cross-check, PL spectra were also recorded on the CCD and found to be identical to those obtained on the fluorometer.

Example 14, device results for G1-Pt-porphyrin 12

Thin films and LED devices were prepared using 12 mixed with Dendrimer A or Dendrimer B (Figure 9). Thin films of the 12/host mixture were formed by spin coating THF solutions (10 mg/ml) of the two dendrimers (host to guest ratio 10:1 w/w, corresponding molar ratio about 3:1). No phase separation was observed for these spin-coated films, and the absorption was found to be the sum of the components. Films of this mixture appeared to be of comparable quality to films prepared from the single substances.

Comparing Examples 7A-7C and 8, the synthesis of A will be described in Comparative Example 7 below.

Dendrimer B is obtained as follows:

1,3,5-tris[(4'-formylstyryl)phenyl]benzene

4-Vinylbenzaldehyde (1.95 g, 14.7 mmol), N,N-dimethylacetamide (40 mL), 1,3,5-tris(4′- Bromophenyl)benzene (2.00g, 3.68mmol), trans-bis(μ-acetyl)-bis[o-(di-o-tolylphosphino)benzyl]dipalladium(II) (10mg, 11μmol) , a mixture of 2,6-di-tert-butyl-p-cresol (646 mg, 29.3 mmol), and sodium carbonate (1.56 g, 14.7 mmol) was deoxygenated. The mixture was then stirred at 130°C for 50.5 hours. Water (100ml) and dichloromethane (100ml) were added. The aqueous layer was separated and extracted with dichloromethane (3x100ml, 2x50ml, 2x100ml). The combined organic layers were washed with water (3 x 500ml) and brine (250ml), dried over anhydrous sodium sulfate, filtered and the solvent was completely removed to leave a yellow/brown solid. Trituration with dichloromethane followed by recrystallization from dichloromethane gave 1,3,5-tris[(4'-formylstyryl)phenyl]benzene (1.24 g, 48%) as a yellow powder , melting point 163°C. Anal _. Calcd. _{for C51H36O3} : C, 87.9; H, 5.2. Measured values: C, 87.4; H, 5.4. ν _max (KBr)/cm ^-1 1690 (C=O) and 962 (C=CH trans).λ _max (CH ₂ Cl ₂ )/nm: 358 (logε/dm ³ mol ^-1 m ^-1 5.10) .δ _H (500MHz, CDCl ₃ ) 7.24 and 7.35 (6H, d, J=16.5Hz, vinylic H), 7.69 (6H, 1/2AA'BB', cp H), 7.77 (6H, 1/2AA'BB ', cp H), 7.71 (6H, 1/2AA 'BB', cp H), 7.86 (3H, s, cep H), 7.91 (6H, 1/2AA 'BB', cp H) and 10.0 (3H, s, CHO); m/n (CI) 697.0 (MH ⁺ , 100%). (vinylic: vinyl)

[G-3] ₃ B9B

Potassium tert-butoxide (171 mg, 1.52 mmol) was added to 1,3,5-tris[(4'-formylstyryl)phenyl]benzene (51.5 mg, 0.07 mmol), Comparative Example 7A (759 mg, 0.30 mmol) in solution in anhydrous tetrahydrofuran (20 mL) heated at reflux. The solution was heated at reflux for 18 hours and then allowed to cool. Water (50ml) and dichloromethane (50ml) were added, and the organic layer was separated. The aqueous layer was extracted with dichloromethane (50ml), then brine (50ml) was added to the aqueous layer before the final extraction with dichloromethane (50ml). The combined organic layers were washed with brine (50ml), dried over anhydrous sodium sulfate, filtered and the solvent was removed. The residue was purified by column chromatography on silica in two steps. The first chromatographic step used a dichloromethane/petroleum ether mixture (2:3) as eluent and the main fractions were collected and the solvent removed. The residue was further purified using dichloromethane/petroleum ether mixture (3:7-2:3) as eluent to afford B (349 mg, 60%). Further, purification by recrystallization from a dichloromethane/methanol mixture gave a yellow oil, which was then triturated with methanol to give a powder, m.p. (decomposition) 281°C. For _C600H690 : C, 91.2; H _, 8.8. Measured values: C, 91.7; H, 9.1.

ν _max (KBr)/cm ^-1 958 (C=CH trans).λ _max (CH ₂ Cl ₂ )/nm: 323(logε/dm ³ mol ^-1 cm ^-1 6.06), 377sh(5.46) and 400sh (5.22).δ _H (400MHz, CDCl ₃ ) 1.40 (432H, s, t-butyl H), 7.18-7.45 (96H, cv H, G-1 vinylH, G-2 vinyl H and G-3 vinyl H) , 7.40 (24H, dd, J=1.5, sp H), 7.46 (48H, d, J=1.5, spH), 7.62-7.82 (87H, cp H, G-1 bp H, 3-2bp H and G- 3 bp H) and 7.90 (3H, s, cep H); m/z (MALDI) 7905.2 (MH ⁺ , 100%); Calc MH ⁺ 7903.1.(t-butyl: tert-butyl)

Absorption spectra of substances A, B and 12 are shown in FIG. 10 . For A, B and 12, it was found that the stilbene moiety would produce an absorption peak at 320 nm. In A the core will give additional absorption at 420 nm, while in B the core will give absorption at 370 nm, while for 12 absorption bands will be observed at 420 nm, 514 nm and 544 nm, corresponding to those of Gl-Pt-porphyrin 12 Soret and Q-spectral bands.

Figure 11 shows the PL and EL spectra of the material mixture under sustained excitation. Upon photoexcitation, the emission of A is green with a peak at 495 nm, while that of B is blue with a peak at 470 nm. In a mixture of the two, the guest dendrimer 12 emits in a near-IR red with a peak of at 662nm and 737nm. Emissions from host dendrimers A and B are due to fluorescence, while emission from guest 12 is believed to be due to phosphorescence. For a mixture of A: 12 and B: 12 , the emission of the host PL will be much stronger than that of the guest PL.

The most surprising result illustrated in Figure 11 is the large difference between the EL spectra of mixture B12 compared to the PL spectra. In contrast to PL, in EL the emission of the guest will be much stronger than the emission of the host in the B:12 mixture. For the mixture of A:12, there is also an increase in the guest emission relative to the host in the EL relative to the PL, but this increase is significantly smaller than in the case of the mixture of B:12. The difference between the EL and PL spectra is due to charge trapping in the EL device, which affects the occurrence of recombination therein. In both mixtures there will be a red shift in the guest EL emission compared to the PL emission. The device can be driven continuously or by pulsed driving. It was also found that the emission spectrum is dependent on driving conditions and duty cycles.

Example 15, Device Results of Ir Dendrimer [2-(4'-G1-Ph)Py] ₃ Ir 10

Devices containing the novel Ir dendrimers 10 were fabricated using standard methods described above. Using pure Ir dendrimer layer and using mixed dendrimer B and PBD (2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole) ) layer preparation device of Ir dendrimers of the mixture. The structures of the two devices are:

ITO/PEDOT/ 10 (140nm)/Al

ITO/PEDOT/Dendrimer B: 10 : PBD/Al

Herein, in the mixture, the weight ratio of dendrimer B: 10 :PBD was 1:0.1:0.4, and two devices were formed, one of which had a 150 nm thick mixed layer and the other had a 200 nm thick mixed layer.

The emission spectra of pure substances and mixtures are shown in FIG. 12 . The iridium dendrimers (10) show a broad EL in green (peak at 535nm with features at 577nm and 623nm). The phenylene dendrimers (B) emit in blue (peak at 460 nm). In a mixture, both host and guest emit. The EL spectrum of a mixture is not just a superposition of guest and host. In thicker devices, the emission band of the host cannot be determined, and there is still a distinct unstructured emission below the band of the iridium dendrimers. Most importantly, a new emission band was observed at 660 nm, which in some cases would form an emission maximum. In a pure 10 setup, this band is not immediately visible.

The EL spectrum of the mixture appears white, while the PL spectrum of the film is green. This indicates that the main characteristic formed in the EL at 660 nm is not due to exciplexes, but due to the formation of intermolecular charge transfer states between host-guest and guest. A strong dependence of the emission spectrum under driving conditions was observed, suggesting that the emission consists of both phosphorescent and fluorescent components.

Example 16, Device Results of Iridium Dendrimer [2-(3′-G1-Ph)Py] ₃ Ir(11)

The EL spectra of dendrimers 11 and 10 are shown in FIG. 13 . The spectrum of 11 is slightly broader and shows fewer electronic vibrational structures. The emission peak is at 518nm, while that of 10 is at 532nm, and has electronic vibrational properties at 569nm. In 11's red trailing launch, there is a noticeable increase. A device consisting of 10's is more effective than a device containing 11's.

Embodiment 17, the device result of G2-Pt-porphyrin (13)

Fabrication of monolayer devices (PEDOT/13/Al) of pure G2-Pt-porphyrin dendrimers (13). In Figure 14, the EL spectrum of 13 is compared with the PL spectrum of the Gl-Pt-porphyrin dendrimer (12). The EL spectra showed stronger weighting of lower energy emission peaks, as previously observed in free base and platinum porphyrin dendrimers.

Example 18

This embodiment of a red-emitting Ir dendrimer is illustrated in Figure 15, and reference numbers are taken accordingly.

(Glppy) ₂ btpIr(III)(111)

Dichloromethane (5 ml) was added to Glppy Ir dimer (9) (411 mg, 0.317 mmol), 2-benzothiophen-2-ylpyridine (10) (1.44 g, 6.83 mmol) and trifluoromethanesulfonic acid Silver (81 mg, 0.31 mmol), and the solution was stirred at room temperature for 5 minutes, then the solvent was completely removed. The reaction is shown in Figure 16. The melt-like mixture was then heated at 150°C for 67.5 hours and allowed to cool. The residue was purified by column chromatography on silica using dichloromethane-petroleum ether (1:2-2:3) as eluent to afford (Glppy) _2btpIr (III)(111)( 130.4 mg, 28%), an orange solid. δ _H (400MHz, CDCl ₃ ) 0.98 (24H, m, CH ₃ ), 1.30-1.60 (32H, m, alkyl H), 1.79 (4H, m, OCH ₂ CH), 3.94 (8H, d, J5. 5, OCH ₂ ) and 6.81-8.05 (41H, m, aryl H). m/z (MALDI) 1681.4 (M ⁺ , 100%).

Under argon atmosphere, for the iridium complex obtained above, cyclic ligand 5 (about 244 mg), 2-(4′-G1-Ph)Py 5 (200 mg, 0.313 mmol) and silver triflate (70 mg , 0.272mmol) of the mixture was heated (bath temperature 130-140°C) for 88h. The reaction mixture was then cooled to room temperature and about 5 ^cm of DCM was added. The tan mixture was purified by column chromatography on silica gel using DCM-ethyl acetate-petroleum ether (0:1:10-1:1:10) as eluent to give 200 mg (for IrCl ₃ . 10 for two steps of 3H ₂ O (49%), an orange-yellow solid; TGA _(5%) 410 °C; (measured: C, 76.8; H, 7.5, N, 2.0. C ₁₃₅ H ₁₅₆ IrN ₃ O _6Calc , 76.9; H, 7.5, N, 2.0%); _λmax /nm (thin film) 277 and 397; _δH (200MHz; CDCl ₃ ) 0.78-1.03 (36H, m, Me), 1.15-1.50 (48H, m, CH ₂ ), 1.52-1.72 (6H, m, CH), 3.65 (12H, m, ArOCH ₂ ), 6.58 (12H, m, ArH), 6.92 (3H, t, J 6.4Hz, PyH ), and 7.32-7.92 (39H, m, ArH &PyH); m/z [MALDI] 2105, 2106, 2107, 2108, 2109, 2110, 2111, 2112, 2113 (M ⁺ ).

Example 19

Examples 19 and 20 forming Re dendrimers are illustrated in FIG. 16 .

Gl-Phen, 31

{3,5-[4′-(2″-ethylhexyloxy)phenyl]phenyl}phenanthroline

method 1

Under argon atmosphere, the compound Gl-BX ₂ (496mg, 0.944mmol) of Comparative Example 6, bromophenanthroline (221mg, 0.858mmol), 2M Na ₂ CO ₃ (aqueous solution) (0.5cm ³ ), EtOH (0.5 cm ³ ) and toluene (1.5 cm ³ ) were degassed for 10 minutes. Tetrakis(triphenylphosphine)palladium(0) (32mg, 0.028mmol) was added to the reaction mixture, then heated at reflux under argon atmosphere for 22h. The reaction mixture was cooled to room temperature and diluted with water (20cm ³ ) and diethyl ether (20cm ³ ). The two layers were separated. The aqueous layer was extracted with diethyl ether (3 x 20 cm ³ ). The organic layer and ether extract were combined, washed with water (1×40 cm ³ ), dried over anhydrous magnesium sulfate, and the solvent was removed. Silica gel column chromatography using methanol-ethyl acetate (1:0-1:10) gave 251 mg (40%) of 31 as a colorless oil;

ν _max /cm ^-1 (KBr) 1607, 1590, and 1512; λ _max (CH ₂ Cl ₂ )/nm 269 (ε/dm ³ mol ^-1 cm ^-1 75850); δ _H (200MHz; CDCl ₃ ) 0.89 -0.99 (12H, m, Me), 1.26-1.59 (16H, m, CH ₂ ), 1.71-1.80 (2H, m, CH), 3.90 (4H, m, ArOCH ₂ ), 7.02 (4H, m, ArH ), 7.57-7.70(8H, m, ArH & PhenH), 7.85(1H, s, PhenH), 7.87(1H, t, J1.6Hz, ArH), 8.27(1H, dd, J8.1 & 1.7Hz, PhenH), 8.43 (1H, dd, J8.4 & 1.6Hz, PhenH), 9.22 (1H, d, J1.6Hz, PhenH), 9.24 (1H, d, J1.6Hz, PhenH); δ _C (50MHz; CDCl ₃ ) 11.1, 14.1, 23.0, 23.8, 29.1, 30.5, 39.4, 70.6, 114.9, 122.9, 123.4, 123.7, 124.8, 126.5, 128.2, 129.7, 132.8, 134.7, 136.0, 138.0, 136.4.8, 14 , 150.1, 150.3, 150.7, 159.3; m/z [MALDI] 1393 (2M+Cu ⁺ ).

Method 2:

Under argon atmosphere, for the first generation of borolane (349mg, 0.57mmol), bromophenanthroline (221mg, 0.855mmol), 2M Na ₂ CO ₃ (aqueous solution) (4cm ³ ), EtOH (4cm ³ ) and toluene (16 cm ³ ) was degassed for 15 minutes. Tetrakis(triphenylphosphine)palladium(0) (21 mg, 0.018 mmol) was then added to the reaction mixture before heating at reflux under argon atmosphere for 22 hours. The mixture was cooled and diluted with water (20cm ³ ) and diethyl ether (20cm ³ ). The organic layer and the extract were combined, washed with water (40cm ³ ) and dried over anhydrous magnesium sulfate. Solvent was removed under vacuum.

Purification on a silica gel column using methanol-ethyl acetate (0:1 to 1:9) as eluent gave 333 mg (88%) of 31 as a colorless oil.

Example 20

G1-Phen Re, 32

Tricarbonyl-chloro-{3,5-[4′-(2″-ethylhexyloxy)phenyl]phenyl}phenanthroline rhenium p-phenanthroline ligand 31 (126mg, 0.190mmol) and A mixture of chlororhenium pentacarbonyl (681 mg, 0.190 mmol) in 10 ^cm of toluene was heated at reflux for 1.5 h. The mixture turned yellow and then orange. The reaction mixture was cooled to ambient temperature and the solvent was removed under reduced pressure. - Petroleum ether as eluent, purification on a silica gel column gave 76 mg (41%) of 32 , a golden yellow powder; νmax/cm ^-1 (KBr) 2021, 1916, 1893; (measured value: C, 60.5 H, _5.5 ; N, 2.8 _{; Calcd} for _{C49H52ClN2O5ReC} , 60.6; H, 5.4; N, 2.9%); _λmax /nm (thin film) 276; m/z [MALDI] 935 (M-Cl).

Examples 21-24

These examples are illustrated in FIG. 17 .

Example 21

PPh-BOR ₂

2-[3′-(4″, 4″, 5″, 5″-tetramethyl-1″, 3″, 2″-dioxaborolan-2″-yl)phenyl]pyridine

To a cold (dry ice/acetone bath) ^solution of 6 (8.10 g, 34.6 mmol) in 130 cm anhydrous tetrahydrofuran was added tert-butyllithium (1.7M, 36.6 cm ³ , 62.1 mmol) under argon atmosphere. The mixture was stirred at -78°C for 2 hours, and then 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (9cm ³ ) Add to cold mixture. The reaction was stirred at -78°C for 2 hours and the dry ice/acetone bath was removed. The mixture was stirred at room temperature for an additional 20 hours before being quenched with water (30 cm ³ ). The two layers were separated. The aqueous layer was extracted ^* with diethyl ether (3 x 40 cm ³ ). The organic layer and ether extract were combined and dried over anhydrous sodium sulfate, then the solvent was completely removed.

^* The aqueous layer was washed with NaHCO ₃ (sat. solution) (1×40 cm ³ ) and extracted with diethyl ether (2×40 cm ³ ), yielding 4.0 g of a yellow solid after drying and removal of solvent. Purification of these crude mixtures by column chromatography on silica gel using DCM-petroleum ether (0:1 to 1:30) as eluent afforded 4.92 g (50%) of 23 as a white solid; ( Measured: C, 72.6; H, 7.2; N, 5.0 _. Calculated for _C17H20BNO2C , 72.6; H, 7.2; N, 5.0 _% ); 72.6; H, _7.2 ; ₂₀ BNO ₂ measurement C, 72.6; H, 7.2; N, 5.0%); δ _H (400MHz; CDCl ₃ ) 1.37 (12H, s, Me), 7.23 (1H, m, PyH), 7.51 (1H, m, ArH), 7.76 (1H, m, PyH), 7.80 (1H, m, ArH), 7.87 (1H, m, PyH), 8.14 (1H, m, ArH), 8.40 (1H, m, ArH), and 8.71 (1H, m, PyH); _δC (101MHz; CDCl ₃ ) 24.9, 83.9, 120.7, 122.0, 128.2, 129.9, 133.2, 135.3, 136.6, 138.7, 149.6, 154.6, and 157.5; m/z [APCI ⁺ ] 283(MH ⁺ ).

Example 22

DBPPh-Py, 24

2-[3'(3",5"-di-bromophenyl)phenyl]pyridine

p-23 (5.15g, 281mmol), 1,3,5-tribromobenzene (6.92g, 315mmol), tetrakis(triphenylphosphine)palladium(0) (846mg, 0.732mmol), 2M Na ₂ CO ₃ (aqueous ) (12cm ³ ), EtOH (12cm ³ ) and toluene (48cm ³ ) were degassed, and then heated under reflux (bath temperature 105-110° C.) for 19.5 h under an argon atmosphere. Allow the mixture to cool. Water (10cm ³ ) and ether (20cm ³ ) were added to the mixture. The two phases were separated. The aqueous layer was extracted with diethyl ether (3 x 20 cm ³ ). The organic layer and ether extract were combined and dried over anhydrous sodium sulfate. Solvent was completely removed. The residue was purified by column chromatography on silica gel using ethyl acetate-petroleum ether (0:1-1:20) as eluent to afford 24 (4.70 g, 66%) as a white solid. (measured: C _, 52.6; H, 2.5, N, _3.6 . _Calcd . for C17H11Br2N C, 52.5; H, 2.9, N, 3.6%);

δ _H (400MHz; CDCl ₃ ) 7.29 (1H, m, PyH), 7.57 (2H, m, ArH), 7.67 (1H, m, ArH), 7.75 (2H, m, ArH), 7.79 (2H, m, PyH), 7.99 (1H, m, _ArH ), 8.19 (1H, m, _ArH ), and 8.74 (1H, m, PyH); , 129.1, 129.4, 132.7, 136.9, 138.9, 140.2, 144.6, 149.8, and 156.8; m/z[EI] 386, 388, 390 (MH ⁺ ).

Example 23

2-(3'-G2-Ph)Py, 25

2-[3′-(3″-{3, 5-bis[4″″-(2″″-ethylhexyloxy)phenyl]phenyl}phenyl)phenyl]pyridine

Before cooling, under an argon atmosphere, the boron compound (G1-BX ₂ ) (4.50 g, 8.48 mmol) of Comparative Example 6, 2-[3′-(3″,5″-di-bromophenyl)benzene yl]pyridine (1.32g, 3.39mmol), tetrakis(triphenylphosphine)palladium(0) (274mg, 0.237mmol), 2M Na ₂ CO ₃ (aq) (3.7cm ³ ), EtOH (3.7cm ³ ) and A mixture of toluene (10 cm ³ ) was degassed and then heated at reflux (bath temperature 110° C.) for 69 hours. The resulting mixture was diluted with water (4cm ³ ) and ether (10cm ³ ). The two layers were separated. The aqueous layer was extracted with diethyl ether (3 x 10 cm ³ ). The organic layer and ether extracts were combined, washed with brine (1 x ^30cm3 ), dried ( _{Na2SO4 )} and the solvent removed to leave a light yellow oil. The oil was purified by column chromatography on silica gel using ethyl acetate-petroleum ether (0:1 to 1:30) followed by DCM-petroleum ether (1:20 to 1:10) as eluent, Obtained 2.97 g (73%) of 25, a white foam; (measured: C, 84.8; H, 8.7; N, 1.1. Calcd. for C ₈₅ H ₁₀₁ NO ₄ C, 85.0; H, 8.5, N, 1.2 %);

λ _max /nm (thin film) 271; δ _H (400MHz; CDCl ₃ ) 0.90-1.02 (24H, m, Me), 1.33-1.60 (32H, m, CH ₂ ), 1.73-1.88 (4H, m, CH) , 3.94 (8H, m, ArOCH ₂ ), 8.05 (8H, m, ArH), 7.23-7.32 (1H, m, PyH), 7.62-7.73 (9H, m, ArH), 7.77-7.90 (9H, m, PyH & ArH), 8.02(3H, m, ArH), 8.07(1H, m, ArH), 8.38(1H, m, ArH), and 8.76(1H, m, PyH); _δC (101MHz; CDCl ₃ ) 11.1, 14.1, 23.1, 23.9, 29.1, 30.5, 39.4, 70.5, 114.9, 120.8, 122.3, 124.4, 124.7, 125.7, 126.1, 126.2, 128.0, 128.4, 129.4, 133.2, 136.8, 140.6, 14.12 142.4, 142.7, 150.0, 157.3, and 159.2; m/z [MALDI] 1201, 1202, 1203, 1204, 1205 (MH ⁺ ).

Example 24

Fac[2-(3′-G2-Ph)Py] ₃ Ir, 27

Fac tri{2-[3′-(3″,5″-bis{3,5-bis[4″″-(2″ethylhexyloxy)phenyl]phenyl}phenyl)benzene base] pyridine} iridium (III)

25 (2.97 g, 2.47 mmol), iridium chloride trihydrate (174 mg, 0.50 mmol), H ₂ O (4 cm ³ ) and 2-ethoxyethanol (13 cm ³ ) under argon atmosphere before cooling Heating (bath temperature: 107° C.) for 60 h. The precipitate ^* was filtered off and purified by silica gel column using DCM-petroleum ether (1:30 to 1:10) to give a yellow solid (900 mg), a chlorine-bridged dimer 26 ; δ _H (500 MHz; CDCl ₃ )0.82-1.08 (96H, m, Me), 1.32-1.63 (128H, m, CH ₂ ), 1.74-1.88 (16H, m, CH), 3.93 (32H, m, ArOCH ₂ ), 6.26 (4H, m , ArH), 6.98 (4H, m, PyH), 7.06 (32H, m, ArH), 7.16 (4H, ArH), 7.71 (32H, m, ArH), 7.80-8.03 (44H, m, ArH & PyH) , 8.18 (4H, m, _PyH ), and 9.51 (4H, m, PyH); , 124.9, 125.5, 128.8, 131.6, 133.8, 134.9, 137.0, 142.5, 142.8, 143.0, 143.5, 145.0, 145.8, 152.2, 159.6, and _{168.8; m/z [MALDI] 2591, 2592, 25093 (C 200 H} IrN ₂ O ₈ -Cl ⁺ ), 2626 (C ₁₇₀ H ₂₀₀ IrN ₂ O ₈ ).

^* Meanwhile, excess 25 (1.96 g) was recovered from the solution after purification by column chromatography on silica gel using ethyl acetate-petroleum ether (1:30 to 1:10) as eluent.

Under an argon atmosphere, a mixture of the iridium complex (900 mg) obtained above, recovered 25 (1.96 g) and silver triflate (300 mg) was heated (bath temperature: 145° C.) for one week. The reaction mixture was then cooled to room temperature. The tan mixture was dissolved in 50 cm ³ of DCM before being purified on a silica gel column using DCM-petroleum ether ⁽ 1:20) as eluent and then concentrated to about 10 cm _3. 27 in two steps of 3H ₂ O > 40%), a yellow solid; TGA _(5%) 400°C; (measured: C, 80.7; H, 8.0,; N, 1.1. C ₂₅₅ H ₃₀₀ IrN calcd for ₃ O ₁₂ (C, 80.8; H, 8.0, N, 1.1%);

λ _max /nm (thin film) 271, 340 (sh), and 390; δ _H (400MHz; CD ₂ Cl ₂ ) 0.82-1.02 (72H, m, Me), 1.28-1.61 (96H, m, CH ₂ ), 1.70-1.84 (12H, m, CH), 3.91 (24H, m, ArOCH ₂ ), 6.97-7.12 (30H, ArH & PyH), 7.22 (3H, m, ArH), 7.43 (3H, m, PyH), 7.72 (24H, m, ArH), 7.78 (3H, m, PyH), 7.82 (6H, m, ArH), 7.93 (12H, m, ArH), 8.02 (3H, m, ArH), 8.09 (6H, m , ArH), and 8.14-8.24 (6H, m, PyH &ArH); m/z [MALDI] 3791 (broad) (M ⁺ ).

Example 25

Example 25 compound Device structure Peak efficiency (PE) (cd/A) Voltage at PE Brightness at PE (cd/m ² ) Maximum brightness and voltage cd/m ² V Turn-on voltage (V) 111G1-btpIrppy2Figure 15 ITO/111(50nm)/Ca(20nm)/Al(100nm) 0.15 13 850 938,13 4.0 111G1-btpIrppy2Figure 15 ITO/111:CBP(20:80wt%)(110nm)/Ca(20nm)/Al(100nm) 3.0 14 1260 3836, 18 6.0 111G1-btpIrppy2Figure 15 ITO/PEDOT(45nm)/111:CBP(20:80wt%)(110nm)/Ca(20nm)/Al(100nm) 3.7 14 390 2388, 20 6.0 111G1-btpIrppy2Figure 15 ITO/111:TCTA(13:87wt%)(45nm)/TPBI(45nm)/LiF(0.6nm)/Ca(20nm)/Al(100nm) 3.2 6.8 60 3713, 15 4.0 27G2-Irppy3Figure 17 ITO/27(120nm)/Ca(20nm)/Al(100nm) 7.0 12 1250 >6000, 17 42 27G2-Irppy3Figure 17 ITO/27(40nm)/BCP(60nm)/LiF(1.2nm)/Al(100nm) 18 6.0 40 >100, 7.0 4.0 27G2-Irppy3Figure 17 ITO/27:TCTA(30:70wt%)/TPBI(60nm)/LiF(1.2nm)/Al(100nm) 35-40 3.8 50-150 5066, 6.0 >3.0 27G2-Irppy3Figure 17 ITO/27:CBP(46:54wt%)/BCP(60nm)/LiF(1.2nm)/Al(100nm) twenty three 6.0 30 1000, 10 4.4 11G1-Irppy3Figure6 ITO/11:TCTA(13:87wt%)/BCP(60nm)/LiF(1.2nm)/Al(100nm) 30 5.0-6.0 100-250 3900, 8.0 33 11G1-Irppy3Figure6 ITO/11:TCTA(13:87wt%)/TPBI(60nm)/LiF(1.2nm)/Al(100nm) 45-50 4.0 114 3005, 6.0 >3.0 32G1-ReFigure16 ITO/32:EHP-TCTA(25:75wt%)(100nm)/Ca(20nm)/Al(100nm) 0.12 8.4 twenty one 250, 15 3.8 11G1-Irppy3 ITO/11:CBP(20:80wt%)/Ca(20nm)/Al(100nm) 28 13.4 3450 11G1-Irppy3 ITO/11:CBP(20:80wt%)(120nm)/LiF/Ca(20nm)/Al(100nm) 37.5 12.2 2250 9970 3.6 11G1-Irppy3 ITO/11:CBP:TPBI(21:51:28wt%)(120nm)/LiF/Ca(20nm)/Al(100nm) 46 8.6 1000 9980 2.7

(Figure: Figure)

The results given above were obtained from devices prepared according to one of the following procedures.

Standard device (without PEDOT)

1. Etch the ITO square material 12×12mm into the 4×12mm ITO strip by acid etching

2. Ultrasonic action for 10 minutes of acetone cleaning

3. Ultrasonic action for 10 minutes of propan-2-ol cleaning

4. Dry the substrate under a stream of dry nitrogen

5. Treat the substrate with oxygen plasma for 5 minutes at 100W

6. Deposition of Dendrimer Films by Spin Coating

7. Place the substrate in a vacuum evaporator

8. Deposit 20 nm of calcium at a rate of 0.1 nm/s under a vacuum of 1 × 10 ^-6 mbar

9. Deposit 100 nm of aluminum at a rate of 0.1 nm/sec under a vacuum of 1×10 ⁻⁶ mbar.

In step 6, a solution concentration of 20 mg/ml is typically used to obtain a film thickness of 100-120 nm, and a concentration of 5 mg/ml is used to obtain a film thickness of 45-50 nm. The solvent is typically ChCl ₃ and the spin rate is 2000 rpm for 60 seconds.

For devices with PEDOT, perform the following steps between steps 5 and 6:

A. Spin-coat PEDOT from aqueous solution for 1 minute at 2500rpm

B. Dry the PEDOT layer in air at 85°C for 5 minutes

TCTA is tris(carbazolyl)triphenylamine. As in Example Z, EHP-TCTA was prepared. CBP is 4,4'-N,N'-dicarbazole-biphenyl. BCP is 2,9-dimethyl-4,7-biphenyl-1,10-phenanthroline. TPBI is 2,2',2"-(1,3,5-phenylene(tris[1-phenyl-1H-benzimidazole].

The 11+ and 27+ devices were prepared in the following manner. ITO substrates were patterned by photolithography, cut into 1″×1″ squares, and washed sequentially with detergent (NH3:H2O2, 1:1) and Clean with deionized water for 1 hour. The dried substrates were transferred into an anhydrous nitrogen atmosphere glove box where they were subjected to _O2 plasma treatment (Emitech K1050X plasma equipment) at 60 W for 4 minutes. Thin films of CBP or TCTA-doped dendrimers were deposited onto substrates by spin coating inside a glove box. Spin coating was performed with a solution in _CHCl3 (CBP and TCTA) or toluene (TCTA) at a concentration of 5 mg/ml for 1 min with a spin speed of 2000 rpm. Without exposure to air, the dried spin-coated films were transferred to the chamber of a vacuum evaporator for subsequent vacuum deposition of organic charge transport layers and/or metal electrodes at low pressure (<10 ⁻⁶ Torr). The thickness of the evaporated layer was monitored by an in-situ quartz microbalance, and the material was deposited at a rate of 0.1-0.5 nm/s.

Devices based on 11 and 27 emit green light with C.I.E. coordinates around (0.31, 0.63), while devices based on 111 emit red light with C.I.E. coordinates around (0.64, 0.35).

From the results in the table it can be seen that for green emitting Ir dendrimers it would be advantageous to mix it with a charge-transfer species (TCTA or CBP). A hole blocking layer (TPBI) between the emissive layer and the cathode will provide further efficiency improvement. It has been found that the ratio of 11 to TCTA is quite flexible and that in the range of 5-10 mol %, the efficiency of the device changes only slightly. Mixing phosphorescent dendrimers with electron transport species (TPBI) and bipolar charge transport species (CBP) would be advantageous as this would enable very high efficiencies to be obtained from devices containing only a single organic layer (Table in the last line).

Example Z

This embodiment is illustrated in FIG. 18 .

EHP-TCTA

Tris(4-{3″,6″-di[4-(2″″-ethylhexyloxy)phenyl]carbazolyl}phenyl)amine

Tris(dibenzylideneacetone)bis-palladium(0)[ _Pd2 (dba)3] (14mg, 0.015mmol) and tri-tert-butylphosphine (10% in hexane, ^0.01cm3 ) were added to Carbazolyl compound (3,6-bis[4′-(2″-ethylhexyloxy)phenyl]carbazole; DEHP-Car) (860 mg, 1.49 mmol), tris(4-bromophenyl)amine (200 mg, 0.415 mmol), sodium tert-butoxide (240 mg, 2.49 mmol) and distilled toluene (1.0 cm ³ ) and degassing of xylene (1.0 cm ³ ) (Schlenk line, evacuated and back filled with argon) The dark purple mixture was again degassed for 4 days before heating at reflux under an argon atmosphere (bath temperature 130° C.). The mixture was cooled, quenched with H ₂ O (0.5 cm ³ ), and washed with DCM -Petroleum ether (0:1 to 1:10) was purified by column chromatography on silica gel as eluent to give 468 mg of 57% Z as a pale tan solid; TGA _(5%) 375° C.; λ _max /nm (thin film) 266, and 304; δ _H (500MHz; CDCl ₃ ) 0.93-1.09 (36H, m, Me), 1.33-1.674 (8H, m, Ch ₂ ), 1.78-1.89 (6H, m, CH ), 3.95 (12H, m, ArOCH ₂ ), 7.07 (12H, m, ArH), 7.54-7.77 (36H, m, ArH & CarH), and 8.40 (6H, m, CarH); δ _c (126MHz; CDCl ₃ ) 11.6, 14.6, 23.6, 24.4, 29.6, 31.1, 39.9, 71.1, 110.6, 115.4, 118.9, 124.5, 125.8, 125.9, 128.5, 128.7, 133.4, 133.9, 134.7, 140.9, 146.8, and 159 mz [MALDI] 1967, 1968, 1769, 1970, 1971 (MH ⁺ ).

Prepare DEHP-Car as follows:

Under argon atmosphere, to 3,6-dibromocarbazole (12.0g, 37.1mmol), boron compound G0-BX2 (comparative example 4) (24.1g, 96.4mmol), tetrakis (triphenylphosphine) palladium (0 ) (800mg, 0.692mmol), 2M Na ₂ CO ₃ (aqueous solution) (40cm ³ ), EtOH (40cm ³ ) and toluene (100cm ³ ) were degassed, then heated under reflux (bath temperature 100°C) for 42h. The mixture was cooled and diluted with water (30cm ³ ) and diethyl ether (40cm ³ ). The two layers were separated. The aqueous layer was extracted with diethyl ether (3 x 40 cm ³ ). The organic layer and ether extracts were combined, washed with brine (1 x 50 cm ³ ) and dried (Na ₂ SO ₄ ). The solvent was completely removed and purified by column chromatography on silica gel using ethyl acetate-petroleum ether (0:1 to 1:10) and DCM-ethyl acetate-petroleum ether (4:1:20) as eluents Purification of <RTI ID=0.0>(69%)</RTI> afforded 14.7 g (69%) of DEHP-Car as a white solid; m/z [APCI ⁺ ] 576 (M ⁺ ).

Example 26

This embodiment of a blue emitting Ir dendrimer is illustrated in Figure 19 and reference numbers are taken accordingly.

G1-styrene (4)

Potassium tert-butoxide (0.98 g, 8.76×10 ^-3 mol) was slowly added to compound (1) [comparative example R3] (3.00 g, 5.84×10 ^-3 mol) and methyltriphenyl iodide (2.83 g, 7.01×10 ⁻³ mol) in a stirred mixture in tetrahydrofuran (30 cm ³ ). The mixture was stirred at RT for 1.5 hours and the solvent was removed in vacuo, the 60-80°C petroleum fraction (75 cm ³ ) was added, the mixture was stirred for 10 minutes, passed through a pad of silica, and the 60-80°C petroleum fraction was used- The product was eluted with DCM (4:1) to obtain a colorless oil.

Yield 2.0 g (67%); δ _H (200 MHz; CDCl ₃ ) 7.60 (m, 6H), 7.35 (s, 1H) 7.02 (d, 4H), 6.85 (dd, 10H), 5.88 (d, 1H) , 5.35(d, 1H), 3.92(d, 4H), 1.78(hept, 2H), 1.70-1.25(m, 16H), 0.96(m, 12H)

2-(2,4-Difluorophenyl)-5-bromopyridine (5)

p-2,4-difluorophenylboronic acid (2) (0.37g, 2.32×10 ^-3 mol), 2,5-dibromopyridine (3) (0.5g, 2.11×10 ^-3 mol), tetrakis(tri A mixture of phenylphosphine)palladium(0) (80mg, 6.96×10 ^-5 mol), aqueous sodium carbonate (2M, 0.2cm ³ ), methanol (0.1cm ³ ) and toluene (1.5cm ³ ) was heated under reflux for 18h. Water (10cm ³ ) and DCM (15cm ³ ) were added, the organic layer was separated, dried over anhydrous magnesium sulfate, filtered and concentrated to a crystalline solid which was purified by two recrystallizations from ethanol.

Yield 240 mg (42%); δ _H (500 MHz; CDCl ₃ ) 8.81 (d, 1H), 8.06 (m, 1H), 7.93 (m, 1H), 7.72 (m, 1H), 7.07 (m, 1H) , 6.98(m, 1H)

Compound (6)

For compound (5) (306mg, 1.13×10 ^-3 mol), compound (4) (696mg, 1.36×10 ^-3 mol), Herrmann's catalyst (12mg, 1.28×10 ^-5 mol), N,N- A mixture of dimethylacetamide (6cm ³ ), sodium carbonate (0.13g) and 2,6-di-tert-butyl-p-cresol (0.14g, 2.86×10 ^-4 mol) was heated at 140°C for 2 days. DCM (10cm ³ ) and water (10cm ³ ) were added, the organic layer was separated, washed with water (10cm ³ ), dried over anhydrous magnesium sulfate, filtered and concentrated to a brown oil which was purified by column chromatography [silica gel, hexane Purification by eluting to DCM; repeated - silica gel, DCM] afforded a light brown oil.

Yield 316 mg (40%) δ _H (200MHz; CDCl ₃ ) 8.91 (d, 1H), 8.10 (m, 2H), 7.86-6.95 (m, 16H), 3.92 (d, 4H), 1.78 (hept, 2H ), 1.70-1.25(m, 16H), 0.96(m, 12H)

Compound (7)

A mixture of compound (6) (450 mg, 6.41×10 ⁻⁴ mol) and palladium on carbon (5% w/w, 34 mg) in tetrahydrofuran (7 cm ³ ) was stirred vigorously for 18 h under hydrogen atmosphere. The mixture was passed through a pad of hypoacetylide and rinsed thoroughly with DCM (75 cm ³ ). The solution was concentrated to a light brown oil which was purified by column chromatography [silica gel, DCM].

Yield 357mg (79%); δ _H (200MHz; CDCl ₃ ) 8.56(d, 1H), 8.00(m, 1H), 7.75-6.85(m, 15H), 3.91(d, 4H), 3.08(s, 4H), 1.78(hept, 2H), 1.70-1.25(m, 16H), 0.96(m, 12H)

Compound (8)

At 140°C, compound (7) (175mg, 2.49×10 ^-4 mol), iridium(III) chloride trihydrate (40mg, 1.13×10 ^-4 mol), 2-butoxyethanol (2.2cm ³ ) and water (0.35cm ³ ) mixture was heated for 20h. DCM (10cm ³ ) and water (10cm ³ ) were added, the organic layer was separated and concentrated to a yellow oil which was purified by column chromatography [silica gel, DCM-petroleum fraction 60-80°C, 1:1] to give a yellow oil . Compound (7) (65 mg, 9.29×10 ^-5 mol) and silver trifluoromethanesulfonate (25 mg, 9.88×10 ^-5 mol) were added, and the mixture was heated at 140° C. for 24 h. The product was purified by column chromatography [silica gel, DCM-petroleum distillate 60-80°C, 1:1, repeated 3 times] to give a yellow glassy solid.

Yield 11 mg (5%) δ _H (400MHz; CDCl ₃ ) 8.16(d, 3H), 7.62-6.82(m, 42H), 6.30(m, 6H), 3.86(m, 12H), 2.70(m, 12H ), 1.73 (hept, 6H), 1.70-1.25 (m, 48H), 0.96 (m, 36H)

The PL data for this dendrimer are as follows:

Thin films of a mixture of compound 8 and CBP (20 wt% of compound 8) were prepared from a 1 mg/ml solution in DCM, spin-coating the dendrimer/CBP mixture at 2000 rpm for 1 min. The CIE coordinates of the PL emission (excited at 333 nm) are: x = 0.144, y = 0.326.

It should be noted that in this example, as with other Ir dendrimer examples, the three groups that coordinate with Ir are all covalently bonded via Ir-C and Ir-N bonds. The covalently bound systems described above are superior in terms of stability to systems in which one of the three coordinating groups is more ionic in nature.

Claims (37)

1. A method of making a light emitting device comprising forming at least one layer comprising an organometallic dendrimer having a metal cation as part of its core, the core being free of magnesium chelated porphyrin; wherein The at least one layer of the organometallic dendrimers is deposited from solution. 2. A method according to claim 1, wherein the dendrimer is in the light emitting layer. 3. A method according to claim 1 or 2, wherein the dendrimer is a luminescent material. 4. A method according to claim 1 or 2, wherein dendrimers are used as uniform layer. 5. A method according to claim 1 or 2, wherein the dendrimer fluoresces in the solid state. 6. A method according to claim 1 or 2, wherein the dendrimers phosphoresce in the solid state. 7. The method according to claim 1 or 2, wherein the dendrimer has at least one dendrite that is inherently at least partially conjugated. 8. The method according to claim 7, wherein the dendrimer has at least two dendrites that are inherently at least partially conjugated. 9. The method of claim 8, wherein all dendrites are inherently at least partially conjugated. 10. The method according to claim 1 or 2, wherein the dendrimer is mixed with at least one other dendrimer and/or polymer and/or molecular substance. 11. A method according to claim 10, wherein the organometallic dendrimer phosphorescent in the solid state and mixed with a corresponding non-metallic dendrimer having the same branches as the organometallic dendrimer shape structure. 12. The method according to claim 10, wherein the molar ratio of organometallic dendrimers to other components is 1:1 to 1:100. 13. The method according to claim 2, comprising forming at least one charge transport layer and/or charge injection layer in addition to the light emitting layer. 14. The method according to claim 1, wherein the organometallic dendrimer has the formula (I): Core-[Dendrite] _n (I) Wherein, the core represents a metal ion or a group comprising a metal ion, n represents an integer of 1 or greater, each dendrite may be the same or different and represents an inherently at least partially conjugated dendritic molecular structure comprising an aryl group and/or heteroaryl or nitrogen and optionally vinyl or ethynyl through sp ² or sp hybridized carbon atoms of said aryl or heteroaryl, vinyl and ethynyl or through N and aryl or A single-bond connection between heteroaryl groups; the core is at the end of a single bond to the sp hybridized ring carbon atom of the first aryl ^or heteroaryl group or to which more than one at least part On the nitrogen of the conjugated dendritic branch; the ring carbon atom or nitrogen forms part of the dendrite. 15. The method according to claim 1, wherein the organometallic dendrimer has the formula (II): Core-[Dendrite ¹ ] _n [Dendrite ² ] _m (II) Wherein the core represents a metal ion or a group comprising a metal ion, n and m may be the same or different and each represent an integer of at least 1, when n is greater than 1 each dendrite ¹ may be the same or different and when ÷m is greater than 1 each A dendrite ² may be the same or different and represents respectively a dendritic structure, at least one of which is conjugated and contains aryl and/or heteroaryl and/or nitrogen and optionally vinyl and/or ethynyl , which are attached via sp ² or sp hybridized carbon atoms of said aryl or heteroaryl, vinyl and ethynyl groups or via a single bond between N and the aryl or heteroaryl; and at branch points and/or The connections between the branch points in dendrite ¹ differ from those in dendrite ² ; the core is terminated by a single bond attached to an sp hybridized ring carbon atom of ^the first aryl or heteroaryl group or Nitrogen to which more than one conjugated dendritic branch is attached; the ring carbon atom or nitrogen forms part of the conjugated dendrite ¹ or dendrite ² and the core terminated at a single bond connects To the first branch point of the other of said dendrite ¹ or dendrite ² ; core, at least one of dendrite ¹ and dendrite ² is luminescent. 16. The method according to claim 1, wherein the organometallic dendrimer has the formula (III): Core-[Dendrite] _n (III) wherein the core represents a metal ion or a group comprising a metal ion, n represents an integer greater than 1, each dendrite may be the same or different and represents an inherently at least partially conjugated dendritic molecular structure comprising aryl and /or heteroaryl or N and optionally vinyl and/or ethynyl through sp ² or sp hybridized carbon atoms of said aryl or heteroaryl, vinyl and ethynyl or through N and aryl or heteroaryl groups, and wherein the connections between adjacent branch points in the dendrite are not all identical, the core is at the end of a single bond connected to the first aryl or Heteroaryl having ^sp2 hybridized ring carbon atoms or nitrogens attached to more than one dendritic branch, said ring carbon atoms or N forming part of said dendrites, the core and/or dendrites being luminescent of. 17. The method of any one of claims 14-16, wherein the dendrite, Dendrite ¹ and/or Dendrite ² does not comprise N as a branch point and is an inherently at least partially conjugated dendritic molecular structure. 18. The method according to any one of claims 1-2 and 14-16, wherein the organometallic dendrimer comprises at least one coordinating group which is not dendritic. 19. A method according to any one of claims 1-2 and 14-16, wherein the metal which is part of the core is not magnesium. 20. A method according to any one of claims 1-2 and 14-16, wherein the metal cation is a cation of a d-block metal. 21. A method according to claim 20, wherein the metal is iridium or rhenium. 22. A method according to any one of claims 1-2 and 14-16, wherein the core comprises metal ions and porphyrin or carboxylate or phenylpyridine. 23. A method according to any one of claims 1-2 and 14-16, wherein the metal ion is only in the center. 24. The method according to any one of claims 1-2 and 14-16, wherein the HOMO-LUMO energy gap of the core is lower than the energy gap of the conjugated portion in the dendrite. 25. A method according to any one of claims 14-16, wherein the HOMO-LUMO energy gap of each part of the dendrite decreases stepwise from the surface to the point of attachment to the core. 26. The method according to any one of claims 14-16, wherein at least one surface group is attached to the distal end of the dendrite. 27. The method according to claim 26, wherein at least one surface group is selected from further reactable alkenes; acrylates or methacrylates; sulfur-containing or silicon-containing groups; sulfonyl groups; polyether groups; ₁ -C ₁₅ alkyl group; amine group; mono-, di- or tri-C ₁ -C ₁₅ alkylamine group; -COOR group, wherein R is hydrogen or C ₁ -C ₁₅ alkyl; -OR Group, wherein R is hydrogen, aryl, or C ₁ -C ₁₅ alkyl or alkenyl; -O ₂ SR group, wherein R is C ₁ -C ₁₅ alkyl or alkenyl; -SR group , wherein R is aryl, or C ₁ -C ₁₅ alkyl or alkenyl; -SiR ₃ group, wherein R is the same or different, and is hydrogen, C ₁ -C ₁₅ alkyl or alkenyl, or - SR' group, wherein R' is aryl or C ₁ -C ₁₅ alkyl or alkenyl, aryl or heteroaryl. 28. A method according to claim 27, wherein the surface groups result in solution processability. 29. The method of claim 27, wherein the surface groups render the dendrimer photopatternable. 30. A method according to any one of claims 1-2 and 14-16, wherein the color of the emission is controlled by the duration and frequency of the driving electrical pulses. 31. A method according to any one of claims 1-2 and 14-16, wherein said light emitting device is a light emitting diode (LED). 32. The method of claim 2, comprising forming at least one organic layer in addition to the light emitting layer. 33. A method according to claim 32, wherein the emissive layer is deposited over the organic layer. 34. The method according to claim 13, wherein the emissive layer is deposited on the charge transport layer and/or the charge injection layer. 35. The method according to claim 1, wherein the organometallic dendrimer is neutral. 36. The method according to claim 1, wherein said dendrimers are deposited by spin coating, printing or dip coating. 37. The method according to claim 1, wherein at least one layer comprising organometallic dendrimers is 10-1000 nm, preferably below 200 nm, more preferably 30-120 nm.

Images