JP2017137258A - Method for producing π-conjugated compound - Google Patents

Abstract

Provided is a method for producing a π-conjugated compound capable of obtaining an N-aryl compound in high yield using an aromatic condensed ring amine containing a Group 14 element or a derivative thereof. The production of a π-conjugated compound having a structure represented by general formula (2) using an amide compound having a structure represented by general formula (1). [X1 is a group 14 element; Ra and Rb are each independently H or a substituent; Y1 is an alkali metal bonded to N; Z1 and Z2 are each independently a substituted / unsubstituted aromatic hydrocarbon ring or aromatic Z1 and Z2 may be omitted; Ar1 is a substituted / unsubstituted aromatic hydrocarbon ring or aromatic heterocycle] [Selection] None

Description

  The present invention relates to a method for producing a π-conjugated compound, and more particularly to a method for producing a π-conjugated compound that can produce a π-conjugated compound in high yield.

Organic electroluminescence (EL) elements that have already been commercialized as electronic displays and flat illumination can be classified according to the light emission mechanism. Fluorescence method using light emission from singlet excitons and light emission from triplet excitons. There are two types of phosphorescence methods that use.
Fluorescent organic EL devices have a problem of low luminous efficiency, and phosphorescent organic EL devices have a problem of disadvantageous for blue light emission. In recent years, a delayed fluorescent method developed to solve these problems has been attracting attention. ing.

  The delayed fluorescence method includes a triplet-triplet anionization (TTA, triplet-triplet fusion: TTF) method in which one singlet exciton molecule is formed by collision of two triplet excitons. Two types of thermal excitation-type (thermally activated delayed fluorescence (TADF)) that use thermal inverse intersystem crossing from triplet excitons to singlet excitons have been found.

  In recent years, the TADF method, in which the phenomenon has been discovered, has a singlet excitation energy and a triplet excitation energy close to each other, and if the fluorescence quantum yield can be increased to 100%, in principle, it can be excited by electric field excitation as in the phosphorescence method. Since all the generated excitons can be converted into light, it can be a low power consumption technology similar to phosphorescence.

  In order to cause the TADF phenomenon, it is necessary to cause reverse intersystem crossing at room temperature or the temperature of the light emitting layer in the light emitting element. For this purpose, the energy difference between the lowest excited singlet level and the lowest excited triplet level ( Hereinafter, it is essential that ΔEst) be extremely small. In order to create such a state with an organic compound, the highest occupied molecular orbital (Highest Occupied Molecular Orbital; also called HOMO, the highest occupied molecular orbital) and the lowest unoccupied molecular orbital (LUMO, lowest) It is desirable that the HOMO and the LUMO in the molecule be localized as far as possible to completely separate them, and the donor unit and acceptor property are within or between the molecules. This can be achieved by providing units.

As the donor unit, a π-conjugated compound of a condensed ring amine such as carbazole is known, and among them, an aromatic condensed ring amine containing a Group 14 element is known to be promising.
As a method for synthesizing a donor unit using an aromatic condensed ring amine containing a Group 14 element as a raw material, an amine compound and an aryl halide are reacted in the presence of a catalyst comprising a base, a trialkylphosphine and a palladium compound, A method for obtaining an arylamine compound (for example, see Patent Document 1) and a method for synthesizing an N-aryl compound from an amine compound and an aryl compound in the presence of a base and a transition metal catalyst (for example, see Patent Document 2). Etc.
However, when synthesizing a donor unit using an aromatic condensed ring amine containing a Group 14 element as a raw material, there is a problem that the conventional synthesis method cannot obtain a high yield because of low reactivity.

JP 10-139742 A US Pat. No. 6,235,938

  The present invention has been made in view of the above-mentioned problems and situations, and the solution is to use aromatic condensed ring amines containing a Group 14 element or derivatives thereof to produce those N-aryl compounds in high yield. It is providing the manufacturing method of (pi) conjugated compound which can be obtained by this.

As a result of studying the cause of the above-mentioned problem in order to solve the above-mentioned problems, the present inventor produced the method for producing a π-conjugated compound of the present invention using a specific strong base from an amine compound or a derivative thereof as a raw material. It was found that an N-aryl compound can be obtained in high yield by using the amide compound as a reactive species, and the present invention has been achieved.
That is, the said subject of this invention is solved by the following means.

  1. A method for producing a π-conjugated compound, characterized by producing a π-conjugated compound having a structure represented by the following general formula (2) using an amide compound having a structure represented by the following general formula (1) .

[In General Formula (1) and General Formula (2), X ₁ represents a Group 14 element. Ra and Rb each represent a hydrogen atom or a substituent. Y ₁ represents an alkali metal bonded to a nitrogen atom. Z ₁ and Z ₂ each represents a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocyclic ring, and _one of Z ₁ and Z ₂ may be omitted.
In General Formula (2), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocyclic ring. ]

  2. A structure represented by the general formula (1) using an amine compound having a structure represented by the following general formula (3) and at least one selected from n-BuLi, sec-BuLi, and tert-BuLi. 2. A method for producing a π-conjugated compound according to item 1, wherein an amide compound having the formula:

[In General Formula (3), X ₁ represents a Group 14 element. Ra and Rb each represent a hydrogen atom or a substituent. Z ₁ and Z ₂ each represents a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocyclic ring, and _one of Z ₁ and Z ₂ may be omitted. ]

3. The amide compound having a structure represented by the general formula (1) is a compound having a structure represented by the following general formula (5),
The compound having a structure represented by the general formula (2) is a compound having a structure represented by the following general formula (6), and a compound having a structure represented by the general formula (3) is: The method for producing a π-conjugated compound according to Item 2, which is a compound having a structure represented by the following general formula (4).

[In General Formula (4) to General Formula (6), X ₁ represents a Group 14 element. Ra and Rb each represent a hydrogen atom or a substituent. Y ₁ represents an alkali metal bonded to a nitrogen atom. R ₁ and R ₂ each independently represent a substituent, and the plurality of R ₁ and R ₂ may be the same as or different from each other. n represents an integer of 0 to 4. In General Formula (6), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocyclic ring. ]

  4). Item 4. The method for producing a π-conjugated compound according to any one of Items 1 to 3, wherein an aryl halide is used.

  5. The method for producing a π-conjugated compound according to item 4, wherein a palladium catalyst having a ligand containing a phosphine and an aromatic hydrocarbon ring is used.

  6). 6. The method for producing a π-conjugated compound according to item 5, wherein the ligand further has a chain alkyl group.

7). The method for producing a π-conjugated compound according to any one of Items 1 to 6, wherein X ₁ is a carbon atom or a silicon atom.

8). 8. The method for producing a π-conjugated compound according to item 7, wherein X ₁ is a silicon atom.

  9. The method for producing a π-conjugated compound according to item 4, wherein the aryl halide has a structure represented by the following general formula (7).

[In General Formula (7), Y ₂ represents a bromine atom or an iodine atom. Y ₃ represents a fluorine atom, a chlorine atom, a bromine atom or an iodine atom. ]

10. The method for producing a π-conjugated compound according to Item 9, wherein Y ₂ is a bromine atom or an iodine atom.

  By the above-mentioned means of the present invention, there is provided a method for producing a π-conjugated compound capable of obtaining an N-aryl compound in a high yield using an aromatic condensed ring amine containing a Group 14 element or a derivative thereof. be able to.

The expression mechanism or action mechanism of the effect of the present invention is not clear, but is presumed as follows.
The Buchwald-Hartwig method is known as a method for synthesizing an N-aryl compound from an amine compound. As a general base used in the method, sodium tert-butoxide (NaO ^t Bu), potassium carbonate (K ₂ CO ₃ ), cesium carbonate (Cs ₂ CO ₃ ) and lithium bis (trimethylsilyl) amide (LiHMDS). These bases were not strong enough to extract hydrogen from amine compounds to amides.
Therefore, in the present invention, it is speculated that a π-conjugated compound could be synthesized in a high yield by generating an amide by a method using a strong base, which is different from the Buchwald-Hartwig method. Yes.

  The method for producing a π-conjugated compound of the present invention produces a π-conjugated compound having a structure represented by the general formula (2) using an amide compound having a structure represented by the general formula (1). It is characterized by that. This feature is a technical feature common to or corresponding to the claimed invention.

  Further, the method for producing a π-conjugated compound of the present invention is at least one selected from an amine compound having a structure represented by the general formula (3) and n-BuLi, sec-BuLi, and tert-BuLi. It is preferable from the viewpoint of reactivity to produce an amide compound having a structure represented by the general formula (1) using

  In the method for producing a π-conjugated compound of the present invention, the amide compound having a structure represented by the general formula (1) is a compound having a structure represented by the general formula (5). The compound having the structure represented by the formula (2) is a compound having the structure represented by the general formula (6), and the compound having the structure represented by the general formula (3) A compound having a structure represented by the formula (4) is preferable from the viewpoint of expression of the effect of the present invention.

  In the method for producing a π-conjugated compound of the present invention, it is preferable to use an aryl halide from the viewpoint of easy organic synthesis.

  In the method for producing a π-conjugated compound of the present invention, it is preferable to use a palladium catalyst having a ligand containing a phosphine and an aromatic hydrocarbon ring because it can be obtained in a high yield.

  In addition, it is preferable that the ligand further has a chain alkyl group from the viewpoint of becoming a highly active palladium catalyst.

In the method for producing a π-conjugated compound of the present invention, it is preferable from the viewpoint of ease of synthesis that X ₁ is a carbon atom or a silicon atom.

In the method for producing a π-conjugated compound of the present invention, it is preferable from the viewpoint of manifesting the effect of the present invention that X ₁ is a silicon atom.

  In addition, in the method for producing a π-conjugated compound of the present invention, it is preferable that the aryl halide has a structure represented by the general formula (7) from the viewpoint of performing the reaction in the next step. .

Furthermore, in the method for producing a π-conjugated compound of the present invention, the Y ₂ is preferably a bromine atom or an iodine atom from the viewpoint of high reactivity and high yield.

  Hereinafter, the present invention, its components, and modes and modes for carrying out the present invention will be described in detail. In addition, "-" shown in the following description is used with the meaning which includes the numerical value described before and behind that as a lower limit and an upper limit.

[Method for producing π-conjugated compound of the present invention]
The method for producing a π-conjugated compound of the present invention produces a π-conjugated compound having a structure represented by the following general formula (2) using an amide compound having a structure represented by the following general formula (1). It is characterized by that.

In General Formula (1) and General Formula (2), X ₁ represents a Group 14 element. Ra and Rb each represent a hydrogen atom or a substituent. Y ₁ represents an alkali metal bonded to a nitrogen atom. Z ₁ and Z ₂ each represents a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocyclic ring, and _one of Z ₁ and Z ₂ may be omitted.
In General Formula (2), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocyclic ring.

(Group 14 elements)
In the general formula (1), the Group 14 element represented by X ₁ is preferably a carbon atom or a silicon atom from the viewpoint of ease of synthesis. Moreover, it can be said that the silicon atom is more useful from the viewpoint of dramatically improving the yield over the conventional Buchwald-Hartwig reaction described later.

(Substituent)
Examples of the substituent represented by Ra and Rb in the general formula (1) and the general formula (2) include an alkyl group (for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a tert-butyl group, a pentyl group, Hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (for example, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (for example, vinyl group, allyl group, etc.), alkynyl group ( For example, ethynyl group, propargyl group, etc.), aromatic hydrocarbon group (also called aromatic carbocyclic group, aryl group, etc.), for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, Anthryl, azulenyl, acenaphthenyl, fluorenyl, phenanthryl, indenyl, Nyl group, biphenylyl group, etc.), aromatic heterocyclic group (for example, furyl group, thienyl group, pyridyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group, triazinyl group, imidazolyl group, pyrazolyl group, thiazolyl group, quinazolinyl group, carbazolyl group) Group, carbolinyl group, diazacarbazolyl group (in which one of carbon atoms constituting the carboline ring of the carbolinyl group is replaced by a nitrogen atom), phthalazinyl group, etc.), heterocyclic group (for example, pyrrolidyl) Group, imidazolidyl group, morpholyl group, oxazolidyl group, etc.), alkoxy group (for example, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxy group ( For example, cyclopentyloxy group, cycl Hexyloxy group etc.), aryloxy group (eg phenoxy group, naphthyloxy group etc.), alkylthio group (eg methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group etc.), cyclo An alkylthio group (eg, cyclopentylthio group, cyclohexylthio group, etc.), an arylthio group (eg, phenylthio group, naphthylthio group, etc.), an alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyl) Oxycarbonyl group, dodecyloxycarbonyl group etc.), aryloxycarbonyl group (eg phenyloxycarbonyl group, naphthyloxycarbonyl group etc.), sulfamoyl group (eg aminosulfonyl) Group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylamino Sulfonyl group, etc.), acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group) , Pyridylcarbonyl group, etc.), acyloxy groups (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylca Bonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylamino) Carbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbo group Group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methylureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group) , Dodecylureido group, phenylureido group, naphthylureido group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group) , Phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group) , Butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl group or heteroarylsulfonyl group (for example, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group (For example, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group, piperidinyl group (also known as piperidinyl group) 2), 2,2,6,6-tetramethylpiperidinyl group, etc.), halogen atoms (eg fluorine atom, chlorine atom, bromine atom etc.), fluorinated hydrocarbon groups (eg fluoromethyl group, trifluoro) Methyl group, pentafluor Ethyl group, pentafluorophenyl group, etc.), cyano group, nitro group, hydroxy group, mercapto group, silyl group (for example, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.), phosphate ester Examples include a group (for example, dihexyl phosphoryl group), a phosphite group (for example, diphenylphosphinyl group), a phosphono group, and the like. The substituent may be further substituted with the exemplified substituent.

(Aromatic hydrocarbon ring / aromatic heterocycle)
Examples of the substituted or unsubstituted aromatic hydrocarbon ring represented by Z ₁ and Z ₂ in the general formula (1) and Ar ¹ in the general formula (2) include a phenyl group, a p-chlorophenyl group, a mesityl group, A tolyl group, a xylyl group, a naphthyl group, an anthryl group, an azulenyl group, an acenaphthenyl group, a fluorenyl group, a phenanthryl group, an indenyl group, a pyrenyl group, a biphenylyl group, and the like. For example, furyl group, thienyl group, pyridyl group, pyridazinyl group, pyrimidinyl group, pyrazinyl group, triazinyl group, imidazolyl group, pyrazolyl group, thiazolyl group, quinazolinyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (carbolinyl group) One of the carbon atoms constituting the carboline ring of Instead shows what was), it can be exemplified phthalazinyl group.

  Moreover, it represents with the said General formula (1) using the amine compound which has a structure represented by following General formula (3), and at least one chosen from n-BuLi, sec-BuLi, and tert-BuLi. It is preferable to produce an amide compound having a structure.

In the general formula (3), X ₁ represents a Group 14 element. Ra and Rb each represent a hydrogen atom or a substituent. Z ₁ and Z ₂ each represents a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocyclic ring, and _one of Z ₁ and Z ₂ may be omitted.
That is, it is represented by the general formula (1) using an amine compound having a structure represented by the general formula (3) and at least one strong base selected from n-BuLi, sec-BuLi and tert-BuLi. A compound that can serve as a target donor unit can be synthesized in high yield from an amide having the above structure.
In addition, the Group 14 element, the substituent, the aromatic hydrocarbon ring, and the aromatic heterocyclic ring in the general formula (3) are synonymous with the general formula (1) to the general formula (2).
Here, the background to the production method of the π-conjugated compound of the present invention, the reaction mechanism, and the outline of the conventional Buchwald-Hartwig reaction will be described.

[Donor unit]
Carbazole is known as a general donor unit. Carbazole is an aromatic condensed ring amine, has high reactivity and is easily available, and is therefore a very easy compound for organic synthesis.
On the other hand, acridan (9,9-dimethylacridane) and phenazacillin (10,10-dimethylphenazacillin), which are aromatic condensed ring amines as well as carbazole, are expected as donor units of TADF compounds.

Acridan is an aromatic condensed ring amine in which three six-membered rings having a non-aromatic nitrogen-containing six-membered ring are condensed (666-membered ring type), and has a donor property stronger than carbazole. Phenazacillin is a 666-membered aromatic condensed ring amine having a non-aromatic six-membered ring containing a silicon atom and a nitrogen atom, and has a stronger donor property than acridan.
Therefore, it seems that using these compounds can satisfy the condition of completely separating HOMO and LUMO, which is one of the conditions for developing TADF performance, more easily than using carbazole. It is.

  By the way, when a tertiary aromatic condensed ring amine having an aryl at the N position is synthesized by reacting an aromatic condensed ring amine such as carbazole with an aryl halide, a reaction using a palladium catalyst and a base is performed. It is common to use. This is called the Buchwald-Hartwig reaction (see Patent Document 1 and Patent Document 2) as described above, and is an extremely versatile reaction in order to obtain the target product in a high yield in the reaction system.

  However, when the Buchwald-Hartwig reaction was attempted using acridan instead of carbazole, it was found that the target product could not be obtained in a high yield because the reactivity was lower than that of carbazole.

[Buchwald-Hartwig reaction]
The reaction mechanism of the Buchwald-Hartwig reaction was shown (see Laszlo Kurti, 1 other "Strategic applications of Named Reaction in Organic Synthesis" 2005, P70). According to this, two routes have been proposed, and amines are involved in both the process 1 and the process 2 of the respective routes. Process 1 is a process in which the amine nitrogen atom undergoes nucleophilic attack (coordination) to the palladium reaction intermediate after oxidative addition. Process 2 is a process in which the nitrogen atom of the amine undergoes nucleophilic attack (coordination) on the palladium reaction intermediate after oxidative addition and subsequent halogen-base exchange.
The role of the base in the reaction is to react with the halogen contained in the palladium reaction intermediate.

(Amine)
Common bases in the Buchwald-Hartwig reaction include sodium tert-butoxide (NaO ^t Bu), potassium carbonate (K ₂ CO ₃ ) and cesium carbonate (Cs ₂ CO ₃ ). These are strong bases and have the effect of facilitating nucleophilic attack (coordination) on the Pd reaction intermediate by strengthening the basicity on the nitrogen atom of the amine. It does not reach to generate. As an example, an estimated reaction mechanism between acridan and NaO ^t Bu was shown.

By using a specific strong base for the aromatic condensed ring amine containing a Group 14 element, an amide (N-) form is generated, which becomes a reactive species. A compound obtained by reacting the aromatic condensed ring amide with an aryl halide in the presence of a palladium catalyst having a ligand containing a specific phosphine in a high yield. I believe.
The reaction to obtain a tertiary amine (N-aryl form) by cross-coupling of an amine and an aryl halide in the presence of a palladium catalyst is a Buchwald-Hartwig reaction, but the reaction used in the present invention is precisely Is not a Buchwald-Hartwig reaction.

  On the other hand, the strong base for generating an amide in the present invention is not particularly limited, but lithium bis (trimethylsilyl) amide (LiHMDS), lithium diisopropylamide (LDA), lithium-2,2,6,6-tetramethylpi Peridide (LiTMP) and n-butyllithium (n-BuLi) are preferable, and BuLi is more preferable. Since these are more powerful strong bases, they remove amide hydrogen atoms to generate amides. As an example, the estimated reaction mechanism when acridan and n-BuLi were used was shown.

  Although the reaction mechanism of the present invention is not clarified, it is presumed that the amide form is a reactive species.

  From the above estimated reaction mechanism, as a more preferable method for producing a π-conjugated compound, an amide compound having a structure represented by the general formula (1) has a structure represented by the following general formula (5). A compound having a structure represented by the general formula (2) is a compound having a structure represented by the following general formula (6), and a structure represented by the general formula (3). The compound which has it is a method of manufacturing as a compound which has a structure represented by following General formula (4).

In general formula (4) to general formula (6), X ₁ represents a Group 14 element. Ra and Rb each represent a hydrogen atom or a substituent. Y ₁ represents an alkali metal bonded to a nitrogen atom. R ₁ and R ₂ each independently represent a substituent, and the plurality of R ₁ and R ₂ may be the same as or different from each other. n represents an integer of 0 to 4. In General Formula (6), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocyclic ring.
The Group 14 elements, substituents, aromatic hydrocarbon rings and aromatic heterocycles in the general formulas (4) to (6) have the same meanings as the general formulas (1) to (3).

(Phosphine ligand)
In the method for producing a π-conjugated compound of the present invention, a palladium catalyst having a ligand containing a phosphine and an aromatic hydrocarbon ring is preferably used. More preferably, the ligand of the palladium catalyst has a chain alkyl group in addition to the phosphine and the aromatic hydrocarbon ring.

(Aryl halide)
The method for producing a π-conjugated compound of the present invention preferably uses an aryl halide.
One of the preferred embodiments of the present invention is to use an aryl dihalide. Specifically, the aryl halide preferably has a structure represented by the following general formula (7).

In General Formula (7), Y ₂ represents a bromine atom or an iodine atom. Y ₃ represents a fluorine atom, a chlorine atom, a bromine atom or an iodine atom.
The Y ₂ is more preferably a bromine atom or an iodine atom.

Halogen Y ₁ aromatic condensed ring nitrogen atoms and dihalogenated in the aryl amine is reacted shows an example of synthesizing the desired compound.
Since the halogen Y ₂ still remains in the N-position aryl of the target compound, it can be used as a reaction point in the next step (for example, cross-coupling reaction, nucleophilic substitution reaction, lithiation reaction, etc.).

Thus as a reaction point Y ₂ of the target product was obtained using the production method of the present invention, for example, there are advantages such as the acceptor units can be easily introduced. Since acridan is a donor unit, a compound having both a donor unit and an acceptor unit in the molecule can be obtained, and TADF performance can be expected.

[Specific examples of π-conjugated compounds according to the present invention]
An example of a π-conjugated compound produced by the method for producing a π-conjugated compound of the present invention is shown below.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "mass part" or "mass%" is represented.
Regarding the method for producing a π-conjugated compound of the present invention, 10,10-dimethyl-9- (4-bromophenyl) -9,10-dihydroacridane (target compound 1) using the production methods of Condition 1 and Condition 9 And the procedure for synthesizing 10,10-dimethyl-9- (4-bromophenyl) -9,10-dihydrophenazacillin (target compound 2) using the production method under Condition 12.
Moreover, the structure of the phosphine ligand of Table 1 is shown.

(Condition 1: Synthesis of target compound 1)
In a 50 mL two-necked eggplant flask, Pd ₂ (dba) ₃ .CHCl ₃ (10.4 mg, 1.0 mol%, 1.00 × 10 ⁻² mmol), TTBP · HBF ₄ (tri-tert-butylphosphonium tetrafluoroborate) Lat, 8.7 mg, 3.0 mol%, 3.00 × 10 ⁻² mmol), NaO ^t Bu (145 mg, 1.5 equiv, 1.5 mmol) were added, and the atmosphere was replaced with nitrogen. Thereafter, dry toluene (3 mL) was added to the reaction vessel, and the mixture was heated and stirred at 100 ° C. for 5 minutes.
Thereafter, 10,10-dimethyl-9,10-dihydroacridan (210 mg, 1.0 mmol), 1-bromo-4-iodobenzene (708 mg, 2.5 equiv, 2.5 mmol), and dry toluene (2 mL) were added. And stirred with heating at 100 ° C. for 28 hours.

  After the reaction, the mixture was filtered through celite, methylene chloride was added to the reaction solution, and the organic layer was extracted by washing with purified water and brine. Thereafter, it was dried over magnesium sulfate, and the solvent was distilled off under reduced pressure. The obtained residue was purified by silica gel chromatography to obtain the target compound 1 (100 mg, yield 28%) as a white solid.

(Condition 9: Synthesis of target compound 1)
To a 50 mL two-necked eggplant flask, 10,10-dimethyl-9,10-dihydroacridan (760 mg, 3.6 mmol) was added and purged with nitrogen. Thereafter, dry toluene (11 mL) was added to the reaction vessel, and the mixture was ice-cooled to 0 ° C. To this solution, 1.55M n-BuLi in n-hexane (2.5 mL, 1.1 equiv, 3.9 mmol) was added dropwise and stirred at 0 ° C. for 1 hour.

Then, Pd ₂ (dba) ₃ .CHCl ₃ (190 mg, 5.0 mol%, 1.8 × 10 ⁻¹ mmol), 2- (di-tert-butylphosphino) biphenyl [JohnPhos] (140 mg, 12.5 mol) %, 4.5 × 10 ⁻¹ mmol), 1-bromo-4-iodobenzene (3.6 g, 3.5 equiv, 13 mmol) and dry toluene (3 mL) were added and stirred at 50 ° C. for 18 hours.

  After the reaction, the mixture was filtered through celite, methylene chloride was added to the reaction solution, and the organic layer was extracted by washing with purified water and brine. Thereafter, it was dried over magnesium sulfate, and the solvent was distilled off under reduced pressure. The obtained residue was purified by silica gel chromatography to obtain the target compound 1 (1.1 g, yield 80%) as a white solid.

(Condition 12: Synthesis of target compound 2)
To a 50 mL two-necked eggplant flask was added 10,10-dimethyl-9,10-dihydrophenazacillin (730 mg, 3.2 mmol), and the atmosphere was replaced with nitrogen. Thereafter, dry toluene (10 mL) was added to the reaction vessel, and the mixture was ice-cooled to 0 ° C. To this solution, a 1.60 M n-BuLi solution in n-hexane (2.2 mL, 1.1 equiv, 3.4 mmol) was added dropwise and stirred at 0 ° C. for 1 hour.

Then, Pd ₂ (dba) ₃ .CHCl ₃ (170 mg, 5.0 mol%, 1.6 × 10 ⁻¹ mmol), 2- (di-tert-butylphosphino) biphenyl [JohnPhos] (120 mg, 12.5 mol) %, 4.0 × 10 ⁻¹ mmol), 1-bromo-4-iodobenzene (3.2 g, 3.5 equiv, 11 mmol) and dry toluene (3 mL) were added and stirred at 50 ° C. for 14 hours.

  After the reaction, the mixture was filtered through celite, methylene chloride was added to the reaction solution, and the organic layer was extracted by washing with purified water and brine. Thereafter, it was dried over magnesium sulfate, and the solvent was distilled off under reduced pressure. The obtained residue was purified by silica gel chromatography to obtain the target compound 2 (0.95 g, yield 78%) as a white solid.

(Consideration of condition: calculation of yield of target compound)
In order to search for optimum reaction conditions, 9,9-dimethyl-10- (4-bromophenyl) acridan (target compound 1) or 10,10-dimethyl-9- (4-bromophenyl) phenazacillin was synthesized by the above-described synthesis method. The yield of (target compound 2) was calculated. Conditions 1 to 14 were examined in the same manner except that the raw materials, base, and phosphine ligand were changed to the compounds shown in Table 1.

  GC-MS measurement was performed on a sample collected from the reaction solution, and the yield of the target compound was determined. Although the reaction temperature and reaction time vary depending on each condition, the reaction temperature is 50 to 100 ° C., the reaction time is 5 to 48 hours, and the yields listed in Table 1 are final. is there.

From the results in Table 1, it was found that the target compound was obtained in high yield when the method for producing a π-conjugated compound of the present invention was used.
Further, when n-BuLi was used as the base, the target compound could be obtained with higher yield.

Claims (10)

A method for producing a π-conjugated compound, characterized by producing a π-conjugated compound having a structure represented by the following general formula (2) using an amide compound having a structure represented by the following general formula (1) .

[In General Formula (1) and General Formula (2), X ₁ represents a Group 14 element. Ra and Rb each represent a hydrogen atom or a substituent. Y ₁ represents an alkali metal bonded to a nitrogen atom. Z ₁ and Z ₂ each represents a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocyclic ring, and _one of Z ₁ and Z ₂ may be omitted.
In General Formula (2), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocyclic ring. ] A structure represented by the general formula (1) using an amine compound having a structure represented by the following general formula (3) and at least one selected from n-BuLi, sec-BuLi, and tert-BuLi. The method for producing a π-conjugated compound according to claim 1, wherein an amide compound having the above is produced.

[In General Formula (3), X ₁ represents a Group 14 element. Ra and Rb each represent a hydrogen atom or a substituent. Z ₁ and Z ₂ each represents a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocyclic ring, and _one of Z ₁ and Z ₂ may be omitted. ] The amide compound having a structure represented by the general formula (1) is a compound having a structure represented by the following general formula (5),
The compound having a structure represented by the general formula (2) is a compound having a structure represented by the following general formula (6), and a compound having a structure represented by the general formula (3) is: The method for producing a π-conjugated compound according to claim 2, wherein the compound has a structure represented by the following general formula (4).

[In General Formula (4) to General Formula (6), X ₁ represents a Group 14 element. Ra and Rb each represent a hydrogen atom or a substituent. Y ₁ represents an alkali metal bonded to a nitrogen atom. R ₁ and R ₂ each independently represent a substituent, and the plurality of R ₁ and R ₂ may be the same as or different from each other. n represents an integer of 0 to 4. In General Formula (6), Ar ¹ represents a substituted or unsubstituted aromatic hydrocarbon ring or aromatic heterocyclic ring. ]   The method for producing a π-conjugated compound according to any one of claims 1 to 3, wherein an aryl halide is used.   The method for producing a π-conjugated compound according to claim 4, wherein a palladium catalyst having a ligand containing a phosphine and an aromatic hydrocarbon ring is used.   The method for producing a π-conjugated compound according to claim 5, wherein the ligand further has a chain alkyl group. The method for producing a π-conjugated compound according to claim 1, wherein X ₁ is a carbon atom or a silicon atom. The method for producing a π-conjugated compound according to claim 7, wherein X ₁ is a silicon atom. The method for producing a π-conjugated compound according to claim 4, wherein the aryl halide has a structure represented by the following general formula (7).

[In General Formula (7), Y ₂ represents a bromine atom or an iodine atom. Y ₃ represents a fluorine atom, a chlorine atom, a bromine atom or an iodine atom. ] The method for producing a π-conjugated compound according to claim 9, wherein Y ₂ is a bromine atom or an iodine atom.