CN116425667A - A non-doped blue light-emitting material containing anthracene, its preparation method and its application in organic electroluminescent devices - Google Patents

Abstract

The invention provides a non-doped blue luminescent material containing anthracene, a preparation method thereof and an application in an organic electroluminescent device, belonging to the technical field of organic photoelectric materials. The non-doped blue luminescent material containing anthracene provided by the present invention has the structure shown in formula I. In the present invention, carbazole, as an effective electron donor group, has advantages such as rigid molecular structure, multiple chemical modification sites, higher chemical and thermal stability; anthracene has strong fluorescence quantum efficiency And good thermal stability, can be used as a π bridge chain; the introduction of benzonitrile realizes the partial overlap and partial separation of the HOMO and LUMO of the blue light material, and obtains a hybrid localized charge transfer state luminescent material with the coexistence of LE state and CT state. It not only improves the photoluminescent efficiency, but also ensures a certain exciton utilization rate, and can reduce the conjugation to ensure the emission of blue light while ensuring the luminous efficiency and thermal stability of the luminescent material.

Description

A non-doped blue light-emitting material containing anthracene, its preparation method and its application in organic electronics Applications in Luminescent Devices

technical field

The invention relates to the technical field of organic photoelectric materials, in particular to a non-doped blue luminescent material containing anthracene, a preparation method thereof and application in organic electroluminescent devices.

Background technique

Organic Light Emitting Diodes (hereinafter referred to as OLED) has the advantages of low energy consumption, high brightness, ultra-thin, light weight, self-illumination, fast response, high color, flexible display, etc., in flat panel display and lighting technology has been widely used.

An organic electroluminescent device is a device prepared by depositing a layer of organic materials between two metal electrodes by spin coating or vacuum evaporation. A classic three-layer organic electroluminescent device includes a hole transport layer, an emitting layer and electron transport layer. Holes generated by the anode pass through the hole transport layer and electrons generated by the cathode combine to form excitons in the light emitting layer through the electron transport layer, and then emit light. In 1987, C.W.Tang et al. (Appl. Phys. Lett. 1987, 51:913-915) of Kodak Corporation of the United States made a milestone breakthrough. Organic electroluminescent devices can adjust and emit various required lights by changing the material of the light-emitting layer according to needs, such as blue light, green light, red light, orange light and white light. Full-color displays require blue, green, and red light-emitting materials with high color purity, high efficiency, long device lifetime, and thermal stability. Compared with the well-developed green and red light materials, exciton injection is difficult due to the wide band gap of the blue light molecule itself. Therefore, research and development of a high-efficiency blue material is very important for improving the performance of organic electroluminescent devices. meaning.

Contents of the invention

In view of this, the purpose of the present invention is to provide a non-doped blue light-emitting material containing anthracene, its preparation method and its application in organic electroluminescent devices. The non-doped blue luminescent material containing anthracene provided by the invention can emit blue light and has good luminous efficiency and thermal stability.

In order to achieve the above-mentioned purpose of the invention, the present invention provides the following technical solutions:

The present invention provides a non-doped blue luminescent material containing anthracene, which has the structure shown in formula I:

In formula I, Cz1 and Cz2 are independently:

Wherein Ar is phenyl, tolyl, naphthyl or biphenyl.

The present invention provides a method for preparing the above-mentioned non-doped blue luminescent material containing anthracene, comprising the following steps:

1,3-dibromo-5-chlorobenzene is subjected to a first coupling reaction with cyanophenylboronic acid having a structure shown in formula a to obtain a compound having a structure shown in formula b;

A compound having a structure shown in formula b is subjected to a second coupling reaction with pinacolate to obtain a compound having a structure shown in formula c;

A compound having a structure shown in formula c is subjected to a third coupling reaction with 9-bromoanthracene to obtain a compound having a structure shown in formula d;

A compound having a structure shown in formula d is subjected to a bromination reaction with N-bromosuccinimide to obtain a compound having a structure shown in formula e;

时，When Cz1 and Cz2 are independently

hour,

1,3-dibromo-5-chlorobenzene is subjected to a fourth coupling reaction with a compound having a structure shown in formula f to obtain a compound having a structure shown in formula g;

A compound having a structure shown in formula g is subjected to a fifth coupling reaction with pinacolate to obtain a compound having a structure shown in formula h;

performing a sixth coupling reaction between a compound having a structure represented by formula h and a compound having a structure represented by formula e, to obtain an anthracene-containing non-doped blue light-emitting material having a structure represented by formula I;

时，When Cz1 and Cz2 are independently

hour,

1,3-dibromo-5-chlorobenzene is subjected to a seventh coupling reaction with a compound having a structure shown in formula i to obtain a compound having a structure shown in formula j;

The compound having the structure shown in formula j is subjected to the eighth coupling reaction with biboronic acid pinacolate to obtain the compound having the structure shown in formula k;

The ninth coupling reaction between the compound having the structure shown in formula k and the compound having the structure shown in formula e is obtained to obtain the non-doped blue light-emitting material containing anthracene having the structure shown in formula I;

Preferably, the first coupling reaction is carried out under the conditions of an alkaline reagent and a catalyst, and the catalyst is tetrakistriphenylphosphine palladium; the temperature of the first coupling reaction is reflux temperature, and the time is 5 to 10 hours;

The second coupling reaction is carried out under the conditions of an alkali reagent and a catalyst, and the catalyst is dichloroditriphenylphosphine palladium; the temperature of the second coupling reaction is reflux temperature, and the time is 5-8 hours.

Preferably, the third coupling reaction is carried out under the conditions of an alkaline reagent and a catalyst, and the catalyst is dichloroditriphenylphosphine palladium; the temperature of the third coupling reaction is reflux temperature, and the time is 5 to 10 h ;

The temperature of the bromination reaction is 0-5° C., and the time is 3-5 hours.

Preferably, the fourth coupling reaction and the seventh coupling reaction are carried out under conditions of an alkaline reagent and a catalyst, and the catalyst is tetrakistriphenylphosphine palladium; the fourth coupling reaction and the seventh coupling reaction The temperature is the reflux temperature, and the time is 5-10 hours.

Preferably, the fifth coupling reaction and the eighth coupling reaction are carried out under the conditions of an alkali reagent and a catalyst, and the catalyst is dichlorobistriphenylphosphine palladium; the fifth coupling reaction, the eighth coupling reaction The temperature of the reaction is the reflux temperature, and the time is 5-8 hours.

Preferably, the sixth coupling reaction and the ninth coupling reaction are carried out under conditions of an alkali reagent and a catalyst, and the catalyst is dichloroditriphenylphosphine palladium; the sixth coupling reaction, the ninth coupling reaction The reaction temperature is the reflux temperature, and the time is 5-10 hours.

The invention provides the application of the above-mentioned non-doped blue luminescent material containing anthracene in organic electroluminescent devices.

The invention provides a non-doped blue luminescent material containing anthracene, which has the structure shown in formula I. The present invention selects carbazole as the electron-pushing group (D group), anthracene as the π-conjugated group, and benzonitrile as the electron acceptor (Acceptor, A) group, and designs and prepares a blue crystal with a D-π-A structure. fluorescent material. Carbazole (Cz) as an effective electron donor group, due to its rigid molecular structure, multiple chemical modification sites, high chemical and thermal stability and other advantages, the introduction of anthracene as a π bridge chain, mainly Anthracene has strong fluorescence quantum efficiency and good thermal stability. The introduction of benzonitrile realizes the partial overlap and partial separation of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of the blue light material, and obtains the LE state The hybridized local charge transfer (HLCT) state luminescent material that coexists with the CT state not only improves the photoluminescence efficiency, but also ensures a certain exciton utilization rate. Both the D group and the A group are connected through the meta position, which can reduce the conjugation and ensure the emission of blue light while ensuring the luminous efficiency and thermal stability.

The invention provides an organic electroluminescence device, which comprises a substrate, a hole injection material layer, a hole transport material layer, a luminescent material layer, an electron transport material layer, an electron injection material layer and a cathode material layer stacked in sequence. The luminescent material layer is the above-mentioned non-doped blue luminescent material containing anthracene. The organic electroluminescent device provided by the invention. Using the anthracene-containing non-doped blue light-emitting material provided by the invention can prepare high-efficiency, low-degree efficiency roll-off, and non-doped organic electroluminescent devices.

Description of drawings

Fig. 1 is a schematic structural diagram of an organic electroluminescent device provided by the present invention.

Detailed ways

The present invention provides a non-doped blue luminescent material containing anthracene, which has the structure shown in formula I:

In formula I, Cz1 and Cz2 are independently:

Wherein Ar is phenyl, tolyl, naphthyl or biphenyl.

表示连接位点。In the present invention,

Indicates the junction site.

As a specific embodiment of the present invention, the non-doped blue light-emitting material containing anthracene has a structure shown in any one of formulas B1-B18, see Table 1 for details.

Table 1 Concrete structure of non-doped blue light-emitting materials containing anthracene

The present invention provides a method for preparing the above-mentioned non-doped blue luminescent material containing anthracene, comprising the following steps:

1,3-dibromo-5-chlorobenzene is subjected to a first coupling reaction with cyanophenylboronic acid having a structure shown in formula a to obtain a compound having a structure shown in formula b;

A compound having a structure shown in formula b is subjected to a second coupling reaction with pinacolate to obtain a compound having a structure shown in formula c;

A compound having a structure shown in formula c is subjected to a third coupling reaction with 9-bromoanthracene to obtain a compound having a structure shown in formula d;

A compound having a structure shown in formula d is subjected to a bromination reaction with N-bromosuccinimide to obtain a compound having a structure shown in formula e;

时，When Cz1 and Cz2 are independently

hour,

1,3-dibromo-5-chlorobenzene is subjected to a fourth coupling reaction with a compound having a structure shown in formula f to obtain a compound having a structure shown in formula g;

A compound having a structure shown in formula g is subjected to a fifth coupling reaction with pinacolate to obtain a compound having a structure shown in formula h;

performing a sixth coupling reaction between a compound having a structure represented by formula h and a compound having a structure represented by formula e, to obtain an anthracene-containing non-doped blue light-emitting material having a structure represented by formula I;

时，When Cz1 and Cz2 are independently

hour,

1,3-dibromo-5-chlorobenzene is subjected to a seventh coupling reaction with a compound having a structure shown in formula i to obtain a compound having a structure shown in formula j;

The compound having the structure shown in formula j is subjected to the eighth coupling reaction with biboronic acid pinacolate to obtain the compound having the structure shown in formula k;

The ninth coupling reaction between the compound having the structure shown in formula k and the compound having the structure shown in formula e is obtained to obtain the non-doped blue light-emitting material containing anthracene having the structure shown in formula I;

In the present invention, 1,3-dibromo-5-chlorobenzene is subjected to a first coupling reaction with cyanophenylboronic acid having the structure shown in formula a to obtain a compound having the structure shown in formula b. In the present invention, the mass ratio of the 1,3-dibromo-5-chlorobenzene to the cyanophenylboronic acid having the structure represented by formula a is preferably 1:1.1-1.3, more preferably 1:1.2.

In the present invention, the first coupling reaction is carried out under the conditions of an alkaline reagent and a catalyst, the alkaline reagent is preferably potassium carbonate, and the catalyst is tetrakistriphenylphosphine palladium. In the present invention, the solvent used in the first coupling reaction is preferably a mixed solution of toluene, ethanol and water, and the volume ratio of the toluene, ethanol and water is preferably 2:1:1.

In the present invention, the first coupling reaction is preferably carried out under nitrogen protection; the temperature of the first coupling reaction is preferably reflux temperature, and the time is preferably 5-10 hours, more preferably 6-8 hours.

In the present invention, after the first coupling reaction, the present invention preferably performs post-treatment on the obtained first coupling reaction solution, and the post-treatment preferably includes:

The first coupling reaction liquid is separated to obtain an organic phase; the organic phase is concentrated and separated by column chromatography to obtain a pure compound having a structure represented by formula b.

In the present invention, the compound having the structure represented by formula b is subjected to the second coupling reaction with pinacolate biborate to obtain the compound having the structure represented by formula c. In the present invention, the mass ratio of the compound having the structure represented by formula b to pinacolate biborate is preferably 1:0.95-1.15, more preferably 1:1.

In the present invention, the second coupling reaction is carried out under conditions of an alkaline reagent and a catalyst, the alkaline reagent is preferably potassium acetate; the catalyst is preferably dichloroditriphenylphosphine palladium; in the present invention, the The solvent of the second coupling reaction is preferably toluene, more preferably anhydrous toluene.

In the present invention, the second coupling reaction is preferably carried out under nitrogen protection; the temperature of the second coupling reaction is preferably reflux temperature, and the time is preferably 5-8 hours, more preferably 6-7 hours.

After the second coupling reaction, the present invention preferably carries out post-treatment to the second coupling reaction solution obtained, and the post-treatment preferably includes:

The second coupling reaction liquid is concentrated, cooled and filtered to obtain the pure compound having the structure shown in formula c.

In the present invention, the compound having the structure represented by formula c is subjected to a third coupling reaction with 9-bromoanthracene to obtain the compound having the structure represented by formula d. In the present invention, the mass ratio of the compound having the structure represented by formula c to 9-bromoanthracene is preferably 2:3.5.

In the present invention, the third coupling reaction is preferably carried out under conditions of an alkaline reagent and a catalyst, the alkaline reagent is preferably potassium carbonate, and the catalyst is preferably dichloroditriphenylphosphine palladium; in the present invention, The solvent of the third coupling reaction is preferably a mixed solution of toluene, ethanol and water, and the volume ratio of the toluene, ethanol and water is preferably 2:1:1.

In the present invention, the third coupling reaction is preferably carried out under nitrogen protection; the temperature of the third coupling reaction is preferably reflux temperature, and the time is preferably 5-10 hours, more preferably 6-8 hours.

After the third coupling reaction, the present invention preferably carries out post-treatment to the third coupling reaction liquid, and the post-treatment preferably includes:

The third coupling reaction liquid is separated to obtain an organic phase; the organic phase is concentrated and separated by column chromatography to obtain a pure compound having a structure represented by formula d.

In the present invention, the compound having the structure represented by formula d is subjected to bromination reaction with N-bromosuccinimide to obtain the compound having the structure represented by formula e. In the present invention, the mass ratio of the compound having the structure represented by formula d to N-bromosuccinimide is preferably 2:0.8. In the present invention, the solvent of the bromination reaction is preferably DMF. In the present invention, the temperature of the bromination reaction is preferably 0-5°C, and the time is preferably 3-5 hours, more preferably 4 hours.

After the bromination reaction, the present invention preferably carries out post-treatment to the gained bromination reaction solution, and the post-treatment preferably includes the following steps:

Add sodium sulfite aqueous solution to the bromination reaction solution to quench the reaction, and precipitate a solid, which is successively filtered, washed with water and washed with ethanol to obtain a pure compound having the structure shown in formula e.

时，1,3-二溴-5-氯苯与具有式f所示结构的化合物进行第四偶联反应，得到具有式g所示结构的化合物。In the present invention, when Cz1 and Cz2 are independently

, 1,3-dibromo-5-chlorobenzene and the compound with the structure of formula f undergo the fourth coupling reaction to obtain the compound with the structure of formula g.

In the present invention, the mass ratio of 1,3-dibromo-5-chlorobenzene to the compound having the structure represented by formula f is preferably 1:2.1-2.5, more preferably 1:2.2-2.4. In the present invention, the fourth coupling reaction is preferably carried out under the conditions of an alkaline reagent and a catalyst, the alkaline reagent is preferably potassium carbonate, and the catalyst is preferably tetrakistriphenylphosphine palladium. In the present invention, the solvent of the fourth coupling reaction is preferably a mixed solution of toluene, ethanol and water, and the volume ratio of the toluene, ethanol and water is preferably 2:1:1.

In the present invention, the fourth coupling reaction is preferably carried out under nitrogen protection; in the present invention, the temperature of the fourth coupling reaction is preferably reflux temperature, and the time is preferably 5 to 10 hours, more preferably 6 to 10 hours. 8h.

After the fourth coupling reaction, the present invention preferably carries out post-treatment to the obtained fourth coupling reaction solution, and the post-treatment preferably includes:

Separating the fourth coupling reaction solution to obtain an organic phase; concentrating and separating the organic phase by column chromatography to obtain a pure compound having a structure represented by formula g.

In the present invention, the compound having the structure represented by formula g is subjected to the fifth coupling reaction with pinacolate biborate to obtain the compound having the structure represented by formula h. In the present invention, the mass ratio of the compound having the structure represented by formula g to pinacolate biborate is preferably 3:1.5.

In the present invention, the fifth coupling reaction is preferably carried out under the conditions of an alkaline reagent and a catalyst, the alkaline reagent is preferably potassium acetate, and the catalyst is preferably palladium dichloroditriphenylphosphine. In the present invention, the solvent for the fifth coupling reaction is preferably toluene, more preferably anhydrous toluene.

In the present invention, the fifth coupling reaction is preferably carried out under nitrogen protection; the temperature of the fifth coupling reaction is preferably reflux temperature, and the time is preferably 5-8 hours, more preferably 6-7 hours.

After the fifth coupling reaction, the present invention preferably carries out post-treatment to the fifth coupling reaction solution obtained, and the post-treatment preferably includes:

The fifth coupling reaction liquid was filtered while hot, concentrated and cooled and filtered sequentially to obtain a pure compound having a structure represented by formula h.

In the present invention, the compound having the structure represented by formula h is subjected to the sixth coupling reaction with the compound having the structure represented by formula e to obtain an anthracene-containing non-doped blue light-emitting material having the structure represented by formula I. In the present invention, the mass ratio of the compound having the structure represented by formula e to the compound having the structure represented by formula h is preferably 1:2.6-3.0, more preferably 1:2.7-2.8.

In the present invention, the sixth coupling reaction is preferably carried out under the conditions of an alkaline reagent and a catalyst. In the present invention, the alkaline reagent is preferably potassium carbonate, and the catalyst is preferably palladium dichloroditriphenylphosphine. In the present invention, the solvent of the sixth coupling reaction is preferably a mixture of toluene, ethanol and water, and the volume ratio of the toluene, ethanol and water is preferably 2:1:1.

In the present invention, the sixth coupling reaction is preferably performed under nitrogen protection; the temperature of the sixth coupling reaction is preferably reflux temperature, and the time is preferably 5-10 hours, more preferably 6-8 hours.

After the sixth coupling reaction, the present invention preferably carries out post-treatment to the sixth coupling reaction solution obtained, and the post-treatment preferably includes:

The sixth coupling reaction liquid is separated to obtain an organic phase; the organic phase is concentrated and separated by column chromatography to obtain a pure non-doped blue light-emitting material containing anthracene having the structure shown in formula I.

时，In the present invention, when Cz1 and Cz2 are independently

hour,

1,3-dibromo-5-chlorobenzene is subjected to a seventh coupling reaction with a compound having a structure shown in formula i to obtain a compound having a structure shown in formula j;

The compound having the structure shown in formula j is subjected to the eighth coupling reaction with biboronic acid pinacolate to obtain the compound having the structure shown in formula k;

The ninth coupling reaction between the compound having the structure represented by formula k and the compound having the structure represented by formula e is carried out to obtain the non-doped blue light-emitting material containing anthracene having the structure represented by formula I.

In the present invention, the specific conditions of the seventh coupling reaction are the same as the fourth coupling reaction, the specific conditions of the eighth coupling reaction are the same as the fifth coupling reaction, and the specific conditions of the ninth coupling reaction are the same as the sixth coupling reaction. The coupling reaction is the same, the only difference lies in the structure of the reaction raw materials, which will not be repeated here.

The invention provides the application of the above-mentioned non-doped blue luminescent material containing anthracene in organic electroluminescent devices.

The present invention provides an organic electroluminescent device, comprising an anode layer, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer and a cathode layer stacked in sequence, and the light-emitting layer is the above-mentioned Anthracene non-doped blue luminescent material.

Preferably, the material of the anode layer is ITO glass.

In the present invention, the material of the hole injection layer is preferably HAT-CN, and the thickness of the hole injection layer is preferably 10-20 nm, more preferably 15 nm.

In the present invention, the material of the hole transport layer is preferably NPB and TATC, the thickness of the NPB is preferably 50-100 nm, more preferably 60-80 nm; the thickness of the TATC is preferably 10-20 nm, more preferably 15nm.

In the present invention, the thickness of the light-emitting layer is preferably 30-50 nm, more preferably 40 nm.

In the present invention, the material of the electron transport layer is preferably TPBI, and the thickness of the electron transport layer is preferably 40-60 nm, more preferably 50 nm.

In the present invention, the material of the electron injection layer is preferably LiF, and the thickness of the electron injection layer is preferably 1-10 nm, more preferably 4-8 nm.

In the present invention, the material of the cathode layer is preferably aluminum. In the present invention, the thickness of the cathode layer is preferably 100-150 nm, more preferably 120-140 nm.

In the present invention, the source of said HAT-CN, NPB, TATC, TPBI is commercially available, and the structural formula is as follows:

In the present invention, the hole injection layer, hole transport layer, light emitting layer, electron transport layer, electron injection layer and cathode layer are preferably deposited by vapor deposition. The present invention has no special requirements on the specific method of vapor deposition, and the method of vapor deposition well known to those skilled in the art can be used.

The non-doped blue light-emitting material containing anthracene provided by the present invention, its preparation method and application in organic electroluminescent devices will be described in detail below in conjunction with the examples, but they should not be understood as limiting the protection scope of the present invention.

Example 1

Preparation of Compound B1

The first step: the preparation of intermediate B1-1

1,3-dibromo-5-chlorobenzene (5g, 18.49mmol), 4-cyanophenylboronic acid (3.0g, 20.42mmol) and potassium carbonate (3.8g, 27.49mmol), then added toluene (50mL), Ethanol (25mL) and deionized water (25mL), added 0.25g tetrakistriphenylphosphine palladium under nitrogen protection, refluxed for 10 hours, cooled, separated, the organic phase was concentrated to dryness, and the crude product was separated by column chromatography to obtain 4.7g of the product. Yield 80%. MS(ESI,m/z):[M] ⁺ calcd for:C ₂₀ H ₁₁ ClN ₂ ,314.1,found,314.3.

The second step: the preparation of intermediate B1-2

The intermediate B1-1 (4g, 12.71mmol), pinacolate (3.9g, 15.36mmol), potassium acetate (3.7g, 37.70mmol) and anhydrous toluene (50mL) were added to a three-necked flask, nitrogen protection 0.2 g of dichloroditriphenylphosphine palladium was added, refluxed for 8 hours, filtered while hot, and the filtrate was concentrated to about 10 mL, cooled and filtered to obtain 3.8 g of the product with a yield of 73%. MS(ESI,m/z):[M+H] ⁺ calcd for:C ₂₆ H ₂₄ BN ₂ O ₂ ,407.2,found,406.9.

The third step: the preparation of intermediate B1-3

9-bromoanthracene (2g, 7.78mmol), intermediate B1-2 (3.5g, 8.61mmol) and potassium carbonate (1.6g, 11.58mmol) were added to a three-necked flask, then toluene (20mL) and ethanol (10mL) were added And deionized water (10mL), under the protection of nitrogen, add 0.1g dichloroditriphenylphosphine palladium, reflux reaction for 10 hours, cooling and liquid separation, the organic phase is concentrated to dryness, and separated by column chromatography to obtain 2.5g product, yield 70% . MS(ESI,m/z):[M+H] ⁺ calcd for:C ₃₄ H ₂₁ N ₂ ,457.2,found,457.4.

The fourth step: the preparation of intermediate B1-4

Intermediate B1-3 (2.0g, 4.38mmol) and DMF (20mL) were placed in a single-necked flask, NBS (0.8g, 4.49mmol) dissolved in DMF (10mL) was added dropwise to the above solution, after stirring for 5h, dropwise The reaction was quenched by adding 30 mL of dilute sodium sulfite aqueous solution, and a solid was precipitated, filtered, washed with water, washed with ethanol, and dried to obtain 2.1 g of the product with a yield of 91%. MS(ESI,m/z):[M] ⁺ calcd for:C ₃₄ H ₁₉ BrN ₂ ,534.1,found,534.2.

Step 5: Preparation of Intermediate B1-5

1,3-dibromo-5-chlorobenzene (2g, 7.40mmol), 4-(9-H-carbazol-9 base) phenylboronic acid (4.5g, 15.67mmol) and potassium carbonate (3.1g, 22.43mmol ), then add toluene (20mL), ethanol (10mL) and deionized water (10mL), add 0.1g tetrakistriphenylphosphine palladium under nitrogen protection, reflux reaction for 10 hours, cooling, liquid separation, organic phase is concentrated to dryness, crude product After column chromatography, 3.1 g of the product was obtained with a yield of 70%. MS(ESI,m/z):[M] ⁺ calcd for:C ₄₂ H ₂₇ ClN ₂ ,594.2,found,594.5.

Step 6: Preparation of Intermediate B1-6

The intermediate B1-5 (3g, 5.04mmol), pinacolate (1.5g, 5.91mmol), potassium acetate (1.5g, 15.28mmol) and anhydrous toluene (30mL) were added to a three-necked flask, nitrogen protection 0.1 g of dichloroditriphenylphosphine palladium was added, refluxed for 8 hours, filtered while hot, and the filtrate was concentrated to about 10 mL, cooled and filtered to obtain 2.5 g of the product with a yield of 72%. MS(ESI,m/z):[M+H] ⁺ calcd for:C ₄₈ H ₄₀ BN ₂ O ₂ ,687.3,found,687.5.

Step 7: Preparation of compound B1

Intermediate B1-4 (1.0g, 1.87mmol), Intermediate B1-6 (1.35g, 1.97mmol) and potassium carbonate (0.39g, 2.82mmol) were added to a three-necked flask, then toluene (10mL) ethanol ( 5mL) and deionized water (5mL), under the protection of nitrogen, add 0.05g dichloroditriphenylphosphine palladium, reflux reaction for 10 hours, cooling and liquid separation, the organic phase is concentrated to dryness, separated by column chromatography to obtain 1.45g product, the yield 76%. ¹ H NMR (400MHz, CDCl ₃ )δ:8.20-8.23(m,4H),7.99-8.02(m,4H),7.89-7.91(m,2H),7.79-7.81(m,2H),7.71-7.76 (m,10H),7.66-7.69(m,4H),7.45-7.47(m,4H),7.40-7.43(m,8H).HRMS(ESI,m/z):[M+H] ⁺ calcd for :C ₇₆ H ₄₇ N ₄ ,1015.3795,found,1015.3798.Anal.:calcd:C,89.91;H,4.57;N,5.52;found:C,89.95;H,4.52;N,5.50.

Example 2

Preparation of Compound B5

The first step: the synthesis of intermediate B5-1

The synthesis method is the same as the intermediate B1-5, and the yield is 75%. MS(ESI,m/z):[M] ⁺ calcd for:C ₄₂ H ₂₇ ClN ₂ ,594.2,found,594.0.

The second step: the synthesis of intermediate B5-2

The synthesis method is the same as the intermediate B1-6, and the yield is 66%. MS(ESI,m/z):[M+H] ⁺ calcd for:C ₄₈ H ₄₀ BN ₂ O ₂ ,687.3,found,687.7.

The third step: the preparation of compound B5

The synthesis method is the same as compound B1, and the yield is 82%. ¹ H NMR (400MHz, CDCl ₃ )δ:8.20-8.23(m,4H),8.01-8.03(m,2H),7.85-7.90(m,4H),7.71-7.78(m,8H),7.66-7.69 (m,4H),7.61-7.64(m,2H),7.53-7.56(m,2H),7.32-7.49(m,16H),7.21-7.29(m,4H).HRMS(ESI,m/z) :[M+H] ⁺ calcd for:C ₇₆ H ₄₇ N ₄ ,1015.3795,found,1015.3796.Anal.:calcd:C,89.91;H,4.57;N,5.52;found:C,89.86;H,4.61; N,5.54.

Example 3

Preparation of compound B8

The first step: the preparation of intermediate B8-1

The synthesis method is the same as that of intermediate B1-1, and the yield is 83%. MS(ESI,m/z):[M] ⁺ calcd for:C ₂₀ H ₁₁ ClN ₂ ,314.1,found,314.4.

The second step: the preparation of intermediate B8-2

The synthesis method is the same as the intermediate B1-2, and the yield is 75%. MS(ESI,m/z):[M+H] ⁺ calcd for:C ₂₆ H ₂₄ BN ₂ O ₂ ,407.2,found,406.8.

The third step: the preparation of intermediate B8-3

The synthesis method is the same as that of intermediate B1-3, and the yield is 72%. MS(ESI,m/z):[M+H] ⁺ calcd for:C ₃₄ H ₂₁ N ₂ ,457.2,found,457.0.

The fourth step: the preparation of intermediate B8-4

The synthesis method is the same as that of intermediate B1-4, and the yield is 91%. MS(ESI,m/z):[M] ⁺ calcd for:C ₃₄ H ₁₉ BrN ₂ ,534.1,found,534.4.

The fifth step: the preparation of intermediate B8-5

The synthesis method is the same as the intermediate B1-5, and the yield is 70%. MS(ESI,m/z):[M] ⁺ calcd for:C ₄₂ H ₂₇ ClN ₂ ,594.2,found,593.9.

Step 6: Preparation of Intermediate B8-6

The synthesis method is the same as the intermediate B1-6, and the yield is 77%. MS(ESI,m/z):[M+H] ⁺ calcd for:C ₄₈ H ₄₀ BN ₂ O ₂ ,687.3,found,687.1.

The seventh step: the preparation of compound B8

The synthesis method is the same as compound B1, and the yield is 75%. ¹ H NMR (400MHz, CDCl ₃ )δ:8.20-8.23(m,4H),8.03-8.06(m,2H),7.94-7.97(m,4H),7.91(s,3H),7.80-7.83(m ,6H),7.64-7.70(m,3H),7.44-7.53(m,10H),7.32-7.43(m,10H),7.20-7.29(m,4H).HRMS(ESI,m/z):[ M+H] ⁺ calcdfor:C ₇₆ H ₄₇ N ₄ ,1015.3795,found,1015.3791.Anal.:calcd:C,89.91;H,4.57;N,5.52;found:C,89.88;H,4.55;N,5.58 .

Example 4

The blue organic electroluminescent device OLEDs prepared as non-doped blue light-emitting material with the compound B1 of Example 1, the structure of the device is: ITO/HAT-CN (10nm)/NPB (50nm)/TATC (10nm)/compound B1(30nm)/TPBI(40nm)/LiF(1nm)/Al(100nm). Device preparation equipment: MB-MO-SE1 vacuum thermal evaporation coating equipment from Mbraun, Germany; testing equipment: Keithley Source 2400, Photo Research PR655 spectrometer.

The compounds used in the device are all commercial products, and the structural formula is as follows:

The specific preparation steps of the device are as follows:

Use 10Ω/sq ITO glass as the substrate, clean it with glass cleaning agent first, then use deionized water and acetone to sonicate 3 times each, and after UV-ozone treatment for 15 minutes, the organic layer is evaporated. First, 10nm of hole injection material HAT-CN was deposited on the ITO glass substrate, then 50nm of NPB was deposited as a hole transport layer, and then 10nm of TATC was deposited as a hole transport layer, followed by evaporation deposition of luminescent material compound B1 to form 30nm light-emitting layer, followed by 40nm electron transport material TPBI, 1nm electron injection material LiF and 100nm cathode aluminum. During material vapor deposition, the pressure of the vacuum chamber is lower than 1×10 ^-4 Pa. The luminous brightness-voltage-current density and current efficiency-current density-external quantum efficiency curves of the device were measured on a Keithley Source 2400 semiconductor performance testing system, and the electroluminescence spectrum was measured on a PhotoResearch PR655 spectrometer. All measurements were carried out at room temperature and atmosphere. The lighting voltage of the prepared device was 3.3V, the maximum luminous brightness was 19775cd/m2, the maximum current efficiency was 9.27cd/A, and the maximum external quantum efficiency was 8.44%.

Example 5

The blue organic electroluminescent device OLEDs prepared as the non-doped blue light-emitting material of embodiment 2 compound B5, the structure of the device is: ITO/HAT-CN (10nm)/NPB (50nm)/TATC (10nm)/compound B5(30nm)/TPBI(40nm)/LiF(1nm)/Al(100nm). The specific device preparation steps are the same as in Example 4. All measurements were carried out at room temperature and atmosphere. The lighting voltage of the prepared device was 3.4V, the maximum luminous brightness was 18641cd/m2, the maximum current efficiency was 9.18cd/A, and the maximum external quantum efficiency was 8.26%.

Example 6

The blue organic electroluminescent device OLEDs prepared as the non-doped blue light-emitting material of embodiment 3 compound B8, the structure of the device is: ITO/HAT-CN (10nm)/NPB (50nm)/TATC (10nm)/compound B8(30nm)/TPBI(40nm)/LiF(1nm)/Al(100nm). The specific device preparation steps are the same as in Example 4. All measurements were carried out at room temperature and atmosphere. The lighting voltage of the prepared device was 3.3V, the maximum luminous brightness was 21260cd/m2, the maximum current efficiency was 9.89cd/A, and the maximum external quantum efficiency was 8.94%.

It can be seen from the test data that the compound provided by the invention is used as a blue light material to obtain a high-efficiency blue light organic electroluminescent device in a non-doped device.

The structural diagrams of the organic electroluminescent devices made by B1, B5, and B8 are shown in Figure 1, and the numbers in Figure 1 indicate the HOMO and LUMO energy levels of the materials in each layer.

The above is only a preferred embodiment of the present invention, it should be pointed out that, for those of ordinary skill in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications can also be made. It should be regarded as the protection scope of the present invention.

Claims (10)

1. An anthracene-containing undoped blue light-emitting material having a structure represented by formula I:

in formula I, cz1 and Cz2 are independently:

wherein Ar is phenyl, tolyl, naphthyl or biphenyl.

2. The method for preparing the anthracene-containing undoped blue light emitting material according to claim 1, comprising the steps of:

performing a first coupling reaction on 1, 3-dibromo-5-chlorobenzene and cyanobenzeneboronic acid with a structure shown in a formula a to obtain a compound with a structure shown in a formula b;

carrying out a second coupling reaction on the compound with the structure shown in the formula b and pinacol biborate to obtain a compound with the structure shown in the formula c;

carrying out a third coupling reaction on the compound with the structure shown in the formula c and 9-bromoanthracene to obtain a compound with the structure shown in the formula d;

brominating a compound with a structure shown in a formula d with N-bromosuccinimide to obtain a compound with a structure shown in a formula e;

when Cz1 and Cz2 are independently

In the time-course of which the first and second contact surfaces,

carrying out a fourth coupling reaction on the 1, 3-dibromo-5-chlorobenzene and a compound with a structure shown in a formula f to obtain a compound with a structure shown in a formula g;

carrying out a fifth coupling reaction on the compound with the structure shown in the formula g and the pinacol diboronate to obtain a compound with the structure shown in the formula h;

carrying out a sixth coupling reaction on the compound with the structure shown in the formula h and the compound with the structure shown in the formula e to obtain an anthracene-containing undoped blue luminescent material with the structure shown in the formula I;

when Cz1 and Cz2 are independently

In the time-course of which the first and second contact surfaces,

carrying out a seventh coupling reaction on the 1, 3-dibromo-5-chlorobenzene and a compound with a structure shown in a formula i to obtain a compound with a structure shown in a formula j;

performing eighth coupling reaction on the compound with the structure shown in the formula j and pinacol biborate to obtain a compound with the structure shown in the formula k;

carrying out a ninth coupling reaction on the compound with the structure shown in the formula k and the compound with the structure shown in the formula e to obtain an anthracene-containing undoped blue luminescent material with the structure shown in the formula I;

3. the method according to claim 2, wherein the first coupling reaction is performed under the conditions of a base reagent and a catalyst, and the catalyst is tetraphenylphosphine palladium; the temperature of the first coupling reaction is reflux temperature and the time is 5-10 h;

the second coupling reaction is carried out under the conditions of an alkali reagent and a catalyst, wherein the catalyst is dichloro diphenyl phosphine palladium; the temperature of the second coupling reaction is reflux temperature and the time is 5-8 h.

4. The preparation method according to claim 2, wherein the third coupling reaction is performed under the conditions of a base reagent and a catalyst, and the catalyst is dichloro-diphenyl-phosphine-palladium; the temperature of the third coupling reaction is reflux temperature and the time is 5-10 h;

the bromination reaction temperature is 0-5 ℃ and the bromination reaction time is 3-5 h.

5. The preparation method according to claim 2, wherein the fourth coupling reaction and the seventh coupling reaction are performed under the conditions of a base reagent and a catalyst, and the catalyst is tetraphenylphosphine palladium; the temperature of the fourth coupling reaction and the seventh coupling reaction is reflux temperature, and the time is 5-10 h.

6. The preparation method according to claim 2, wherein the fifth coupling reaction and the eighth coupling reaction are performed under the conditions of a base reagent and a catalyst, and the catalyst is dichloro diphenyl phosphine palladium; the temperature of the fifth coupling reaction and the eighth coupling reaction is reflux temperature, and the time is 5-8 h.

7. The preparation method according to claim 2, wherein the sixth coupling reaction and the ninth coupling reaction are performed under the conditions of a base reagent and a catalyst, and the catalyst is dichloro diphenyl phosphine palladium; the temperature of the sixth coupling reaction and the ninth coupling reaction is reflux temperature, and the time is 5-10 h.

8. The use of the anthracene-containing undoped blue light-emitting material according to claim 1 or the anthracene-containing undoped blue light-emitting material prepared by the preparation method according to any one of claims 2 to 7 in an organic electroluminescent device.

9. An organic electroluminescent device comprising an anode layer, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer and a cathode layer which are sequentially stacked, wherein the light emitting layer is the non-doped blue luminescent material containing anthracene according to claim 1 or the non-doped blue luminescent material containing anthracene prepared by the preparation method according to any one of claims 2 to 7.

10. The organic electroluminescent device of claim 9, wherein the anode layer is made of ITO glass, the hole injection layer is made of HAT-CN, the hole transport layer is made of NPB and TATC, the electron transport layer is made of TPBI, the electron injection layer is made of LiF, and the cathode layer is made of aluminum.

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