CN111533886A - A class of donor-acceptor polymers containing fused ring units based on quinoxaline benzotriazole and their preparation method and application - Google Patents

Abstract

The invention discloses a donor-receptor type polymer containing a condensed ring unit based on quinoxalinebenzotriazole, and a preparation method and application thereof. The intermediate, the polymeric monomer and the target polymer semiconductor material have the advantages of short synthetic route steps, high total yield, good repeatability, easiness in amplified synthesis and production and the like. Such polymers also have absorption over a broad spectral range and high electron mobility. The donor-acceptor type polymer based on the quinoxaline benzotriazole-based fused ring unit can be used as an active layer and applied to organic/polymer electronic devices such as organic/polymer photodetectors and organic/polymer solar cells.

Description

A kind of donor-acceptor type polymer containing fused ring unit based on quinoxaline benzotriazole and its preparation method and application

technical field

The invention belongs to the field of organic optoelectronics, and in particular relates to a kind of donor-acceptor type polymer containing a quinoxaline-ac-benzotriazole-based fused ring unit and a preparation method and application thereof.

Background technique

Organic solar cell materials, which started in the 1990s, are a new type of sustainable and renewable low-cost green energy materials. They are easy to prepare large-area flexible batteries and have great application potential. Organic field effect transistors are transistor devices with organic semiconductor materials as the active layer. They have attracted extensive attention due to their low cost, flexibility and flexibility and the ability to fabricate large-area devices. Therefore, the field of organic optoelectronics has attracted the attention and investment of many research institutions and scientific research teams in the world, and the development of new efficient and stable materials is the focus of attention in the field of organic optoelectronics.

Photodetectors are components that convert optical signals into electrical signals based on the photoelectric effect, and have important applications in optical communication, image sensing, biomedical sensing, environmental monitoring, meteorology, and military. Currently commonly used photodetectors are generally based on inorganic semiconductor materials, such as Si-based, Ge-based, and InGaAs.

Compared with inorganic materials, organic/polymer materials have the advantages of low cost, easy adjustment of absorption wavelength, film formation by solution method, and easy attachment on different substrates, which make organic/polymer solar cells and organic/polymer photodetectors, etc. Organic electronic components have a simple manufacturing process, low production cost, light weight, easy large-area preparation, and can realize flexible devices, and have broad application prospects.

SUMMARY OF THE INVENTION

In order to overcome the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a kind of donor-acceptor type polymer containing quinoxaline benzotriazole-based fused ring units and its preparation method and application. The invention is based on a quinoxaline benzotriazole-based condensed ring unit with strong electric absorption, and constructs a new type of donor-acceptor type polymer semiconductor material together with an electron donating unit.

The primary object of the present invention is to provide a new class of donor-acceptor type polymers, which are composed of quinoxaline benzotriazole-based fused ring units and electron donating units. Such polymers have narrow band gaps and broad absorption spectra, and the spectra are easily tunable by structure, which can be used to fabricate high-efficiency organic/polymer electronic devices, especially organic/polymer photodetectors and organic/polymeric photodetectors. Polymer solar cells.

Another object of the present invention is to provide a method for preparing the above-mentioned donor-acceptor type polymer containing a quinoxaline benzotriazole-based fused ring unit.

Another object of the present invention is to provide the application of the above-mentioned donor-acceptor type polymer containing a quinoxaline benzotriazole-based fused ring unit in the field of organic optoelectronics.

The object of the present invention is achieved by at least one of the following technical solutions.

The present invention provides a class of donor-acceptor polymers containing quinoxaline benzotriazole-based fused ring units (D-π-A containing quinoxaline benzotriazole-based fused ring units type polymer), the chemical structural formula satisfies the following general formula:

In the formula, x and y are the mole fractions of each unit, where 0<x≤1, 0≤y<1, x+y=1; n is the number of repeating units, and n is an integer greater than 1;

R ₁ and R ₂ are respectively an alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 3 to 30 carbon atoms, an aromatic hydrocarbon group having 6 to 60 carbon atoms, or an aromatic hetero group having 3 to 60 carbon atoms. ring base;

Ar is an aromatic hydrocarbon group having 6 to 100 carbon atoms or an aromatic heterocyclic group having 3 to 100 carbon atoms.

Further, the Ar unit is preferably one or more of the following structures or halogenated, deuterated, and alkyl-substituted derivatives of the following structures:

wherein R ₃ is an alkyl group with 1 to 30 carbon atoms, a cycloalkyl group with 3 to 30 carbon atoms, an aromatic hydrocarbon group with 6 to 60 carbon atoms, or an aromatic heterocyclic group with 3 to 60 carbon atoms.

The present invention provides a method for preparing the above-mentioned donor-acceptor type polymer containing quinoxaline benzotriazole-based fused ring units, comprising the following steps:

(1) under the protection of inert gas, the Ar unit monomer containing bisalkyl tin functional group and the A unit monomer based on the fused ring unit of quinoxaline benzotriazole are dissolved in a solvent, and then a catalyst is added to obtain The mixed solution is heated to carry out Stille polymerization to obtain the mixture after the polymerization;

(2) After purifying the mixture in step (1), the donor-acceptor type polymer containing the quinoxaline benzotriazole-based fused ring unit is obtained.

Further, the solvent described in step (1) includes but is not limited to at least one of toluene, tetrahydrofuran, xylene, chlorobenzene, dichlorobenzene, etc.; the catalyst is a Stille polymerization catalyst, and the catalyst includes but is not limited to four At least one of (triphenylphosphine)palladium, tris(dibenzylideneacetone)dipalladium/tris(o-methylphenylphosphine); the quinoxaline-benzotriazole-based fused ring unit The A unit monomer is a dibrominated quinoxaline benzotriazole-based fused ring unit A unit monomer or a diiodo quinoxaline benzotriazole-based fused ring unit A unit monomer The dosage of the catalyst is 2‰～3% of the total molar amount of the reaction monomers; in the mixed solution, the molar amount of the Ar unit monomer containing the dialkyltin functional group is the same as the quinoxaline acene-based molar amount of the monomer. The molar amount of the A unit monomer of the fused ring unit of the triazole is equal; the structural formula of the Ar unit monomer containing the dialkyltin functional group is one of the following structural formulas:

wherein R ₃ is an alkyl group with 1 to 30 carbon atoms, a cycloalkyl group with 3 to 30 carbon atoms, an aromatic hydrocarbon group with 6 to 60 carbon atoms, or an aromatic heterocyclic group with 3 to 60 carbon atoms.

The general structural formula of the A unit monomer based on the fused ring unit of quinoxaline benzotriazole is as follows:

In the formula, R ₁ and R ₂ are respectively an alkyl group with 1 to 30 carbon atoms, a cycloalkyl group with 3 to 30 carbon atoms, an aromatic hydrocarbon group with 6 to 60 carbon atoms, or an alkyl group with 3 to 60 carbon atoms. Aromatic heterocyclic group, X is a bromine atom or an iodine atom.

The amount of the dialkyltin functional group-containing Ar unit monomer and the dibromo or iodo quinoxaline benzotriazole-based fused ring unit A unit monomer meets the requirement of the dialkyltin functional group-containing amount. The total molar amount of monomers is equal to the total molar amount of monomers containing dibromo and/or diiodine functional groups.

Further, the temperature of the Stille polymerization reaction in step (1) is 60-180° C., and the time of the Stille polymerization reaction is 0.5-72 hours.

Further, the purification in step (2) includes: cooling the polymerized mixture to room temperature, adding dropwise to the stirring methanol for precipitation, filtering, and drying to obtain a crude product, which is successively extracted with methanol and acetone, Dissolved in chlorobenzene, concentrated and precipitated again in methanol solution, filtered and dried to obtain the target product of the donor-acceptor polymer containing fused ring units based on quinoxaline benzotriazole.

Preferably, the preparation method of the donor-acceptor type polymer containing quinoxaline benzotriazole-based fused ring units provided by the present invention comprises the following steps:

(1) Under the protection of inert gas, the Ar unit monomer containing bisalkyl tin functional group and the A unit monomer based on the fused ring unit of quinoxaline benzotriazole are dissolved in a solvent, and heated to carry out Stille polymerization reaction , to obtain a mixture; add alkyl tin thiophene to the mixture, carry out the first insulation reaction, then add bromothiophene, carry out the second insulation reaction, and obtain a reaction solution;

(2) After purifying the reaction solution in step (1), the donor-acceptor type polymer containing the quinoxaline-benzotriazole-based fused ring unit is obtained.

Further, the dosage of the alkyl tin thiophene is 10-40% of the total molar amount of the reaction monomers; the dosage of the bromothiophene is 1-20 times the molar amount of the alkyl tin thiophene; the first heat preservation The reaction time is 6 to 12 hours; the time of the second incubation reaction is 6 to 12 hours.

The step of adding alkyl tin thiophene and bromothiophene in step (1) and then carrying out the heat preservation reaction is not an optional step, and can be omitted if necessary.

The donor-acceptor polymer containing quinoxaline benzotriazole-based fused ring units provided by the present invention can be used in the preparation of electronic devices. The electronic devices include organic/polymer photodetectors, organic/polymer solar cells, organic/polymer thin film transistors, organic/polymer light-emitting transistors, organic/polymer phototransistors, organic/polymer organic light-emitting electrochemical cells more than one of them.

The donor-acceptor polymers containing quinoxaline benzotriazole-based fused ring units provided by the present invention can be applied in organic/polymer electronic devices, especially organic/polymer photodetectors and organic/polymeric applications in solar cells.

The application of the donor-acceptor polymer containing quinoxaline benzotriazole-based fused ring units provided by the present invention in the preparation of electronic devices includes: The donor-acceptor type polymer of the fused ring unit or mixed with at least one other substance is dissolved in an organic solvent, and then formed into a film by spin coating, inkjet printing or printing to obtain the active layer of organic/polymer electronic devices ; Described organic solvent includes but is not limited to more than one in xylene, tetrahydrofuran, chlorobenzene, dichlorobenzene.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

(1) The donor-acceptor type polymer provided by the present invention containing a fused ring unit based on quinoxaline benzotriazole, the D unit and the A unit are directly connected, the planarity is strong, and the donor-acceptor The bulk effect is more pronounced; it has a wider absorption range and a narrower band gap; the solubility is easily regulated by the alkyl chain attached to the benzotriazole and quinoxaline;

(2) The donor-acceptor polymer containing quinoxaline benzotriazole-based fused ring units provided by the present invention has high electron mobility, which is beneficial to the preparation of high-efficiency organic electronic devices, especially Organic/polymer batteries and organic/polymer photodetectors;

(3) The preparation route of the quinoxaline-benzotriazole-based donor-acceptor compound of the present invention is short, the raw materials are readily available, the method is simple, can be prepared in high yield, and can be widely used in scale-up synthesis and production in the industry .

Description of drawings

Fig. 1 is the absorption spectrum of polymer P1 in solid-state thin film on quartz plate;

Fig. 2 is the absorption spectrum of polymer P3 solid-state thin film on the quartz plate;

Fig. 3 is the absorption spectrum of solid-state thin film of polymer P6 on the quartz plate and the absorption spectrum of the solution using chloroform as a solvent in a quartz cuvette;

Fig. 4 is the dark current-voltage ( _Jd -V) curve of polymer photodetector device based on polymer P3;

Figure 5 shows the detectivity of the polymer photodetector device based on polymer P3 under -0.1V bias.

Detailed ways

The specific implementation of the present invention will be further described below with reference to examples, but the implementation and protection of the present invention are not limited thereto. It should be pointed out that, if there are any processes that are not described in detail below, those skilled in the art can realize or understand them with reference to the prior art. If the reagents or instruments used do not indicate the manufacturer, they are regarded as conventional products that can be purchased in the market.

Example 1

Preparation of compound 7

(1) Preparation of compound 1

Under nitrogen protection, benzothiadiazole (6.81 g, 50 mmol) was dissolved in 200 mL of concentrated sulfuric acid, N-bromosuccinimide (18.71 g, 105 mol) was added in three batches at 60 °C, and stirred for 12 Hour. The reaction solution was poured into 900 mL of ice water, filtered with suction, and the filter residue was washed three times with deionized water, methanol and n-hexane successively. This operation was repeated three times, and the finally obtained filter residue was dried to obtain a solid product with a yield of 69%. The results of ¹ H NMR, ¹³ CNMR, MS and elemental analysis indicated that the obtained compound was the target product.

(2) Preparation of compound 2

Under nitrogen protection, compound 1 (5.0 g, 17 mmol) and reduced iron powder (11.40 g, 204 mmol) were dissolved in 100 mL of anhydrous acetic acid, and the reaction solution was heated to 150° C. for 3 hours. After cooling, diatomaceous earth was added for suction filtration, the filtrate obtained by suction filtration was added with water and dichloromethane for extraction, the obtained organic phase layer was spin-dried and then extracted twice with dichloromethane and water, and a solid product was obtained after spin-drying , the yield was 92%. The results of ¹ H NMR, ¹³ CNMR, MS and elemental analysis indicated that the obtained compound was the target product.

(3) Preparation of compound 3

Under nitrogen protection, compound 2 (4.0 g, 15 mmol) was dissolved in 100 mL of anhydrous acetic acid, sodium nitrite (1.56 g, 22.56 mmol) was dissolved in 20 mL of deionized water, and added dropwise to the reaction through a constant pressure dropping funnel in the system. After all the dropwise additions were completed, the reaction was carried out for 6 hours. The reaction solution was suction filtered, the filter residue was washed three times with deionized water, and the obtained filter residue was dried to obtain a solid product with a yield of 77%. The results of ¹ H NMR, ¹³ CNMR, MS and elemental analysis indicated that the obtained compound was the target product.

(4) Preparation of compound 4

Under nitrogen protection, compound 3 (5.54 g, 20.0 mmol) and potassium carbonate (5.53 g, 40.0 mmol) were dissolved in 200 mL of N,N-dimethylformamide dehydrated with magnesium sulfate and 5 mL of dimethylmethylene In the mixed solvent of sulfone, the reaction solution was heated to 80°C for 1 hour, then 2-n-butyl-1-bromooctane (5.98g, 24.0mmol) was added under nitrogen protection, and the reaction solution was heated to 90°C for reaction 12 hours. After cooling, the reaction solution was poured into cold water, and the product was extracted with water and dichloromethane, repeated 3 times. It was purified by column chromatography, using 200-300 mesh silica gel as the stationary phase, and the polarity of the eluent was petroleum ether/dichloromethane (4:1) to obtain a light yellow oily liquid product with a yield of 72%. The results of ¹ H NMR and ¹³ CNMR indicated that the obtained compound was the target product.

(5) Preparation of compound 5

Under nitrogen protection, a mixed acid of concentrated sulfuric acid (40 mL) and fuming nitric acid (40 mL) was added to the three-necked flask, the three-necked flask was placed in an ice bath and cooled to 0° C. Compound 4 (4.45 g, 10.0 mmol) was divided into 4 times, slowly added to the mixed acid at 10-minute intervals. The three-necked flask was moved to room temperature to continue the reaction for 6 hours after being placed in an ice bath to react for 1 hour. The reaction solution was poured into ice water, filtered with suction, and the filter residue was washed three times with water. Then, it was purified by column chromatography, using 200-300 mesh silica gel as the stationary phase, and the polarity of the eluent was petroleum ether/dichloromethane (2:1) to obtain a light yellow solid product with a yield of 55%. The results of ¹ H NMR, ¹³ CNMR, MS and elemental analysis indicated that the obtained compound was the target product.

(6) Preparation of compound 6

Under nitrogen protection, compound 5 (1.07 g, 2.0 mmol) and reduced iron powder (1.34 g, 24.0 mmol) were dissolved in 100 mL of anhydrous acetic acid, and reacted at 60° C. for 4 hours. After cooling, the reaction solution was poured into water, extracted three times with dichloromethane and water, and then purified by column chromatography, using 200-300 mesh silica gel as the stationary phase, and the polarity of the eluent was petroleum ether/dichloromethane. (2:1) to give the product as a light grey solid in 91% yield. The results of ¹ H NMR, ¹³ CNMR, MS and elemental analysis indicated that the obtained compound was the target product.

(7) Preparation of compound 7

Under nitrogen protection, the compound (0.72 g, 1.50 mmol) was dissolved in 60 mL of anhydrous acetic acid, and diacetyl (274 mg, 3.18 mmol) was added dropwise to the reaction solution, and the reaction was carried out at 50° C. for 12 hours. After cooling, the reaction solution was poured into water, extracted three times with dichloromethane and water, and then purified by column chromatography, using 200-300 mesh silica gel as the stationary phase, and the polarity of the eluent was petroleum ether/dichloromethane. (1:2). Recrystallization from methanol gave a yellow solid product in 81% yield. The results of ¹ HNMR, ¹³ CNMR, MS and elemental analysis indicated that the obtained compound was the target product.

The chemical reaction equations for the synthesis of compounds 1 to 7 are shown below:

Example 2

Preparation of compound 11

(1) Preparation of compound 8

For the preparation of compound 3, refer to Example 1. Under nitrogen protection, compound 3 (5.54 g, 20.0 mmol) and potassium carbonate (5.53 g, 40.0 mmol) were dissolved in 180 mL of N,N-dimethylformamide dehydrated with magnesium sulfate and 5 mL of dimethylmethylene In the mixed solvent of sulfone, the reaction solution was heated to 85°C for 1 hour, then 1-bromohexane (3.32 g, 24.0 mmol) was added under nitrogen protection, and the reaction solution was heated to 90°C for 8 hours. After cooling, the reaction solution was poured into cold water, and the product was extracted with water and dichloromethane, repeated 3 times. Purified by column chromatography, using 200-300 mesh silica gel as the stationary phase, and the polarity of the eluent is petroleum ether/dichloromethane (volume ratio 4:1) to obtain a light yellow oily liquid product with a yield of 68% . The results of ¹ H NMR and ¹³ CNMR indicated that the obtained compound was the target product.

(2) Preparation of compound 9

Under nitrogen protection, trifluoromethanesulfonic acid (37.51 g, 250.0 mmol) was first added to the three-necked flask, the three-necked flask was placed in an ice bath and cooled to 0° C., and concentrated sulfuric acid (6.30 g, 100.0 mmol) was added dropwise. The reaction system was cooled in an ice bath for 30 minutes and brought to room temperature, and the compound (3.61 g, 10.0 mmol) was added to the reaction system at room temperature in 6 portions at 5 minute intervals. Then, the reaction solution was heated to 50°C and reacted for 6 hours. After cooling, the reaction solution was poured into a large amount of ice water, filtered with suction, and the filter residue was washed three times with water. Then, it was purified by column chromatography, using 200-300 mesh silica gel as the stationary phase, and the polarity of the eluent was petroleum ether/dichloromethane (3:2) to obtain a pale yellow solid product with a yield of 47%. The results of ¹ H NMR and ¹³ CNMR indicated that the obtained compound was the target product.

(3) Preparation of compound 10

Under nitrogen protection, compound 9 (2.26 g, 5.0 mmol) and reduced iron powder (3.36 g, 60.1 mmol) were dissolved in 200 mL of anhydrous acetic acid, and reacted at 60° C. for 4 hours. After cooling, the reaction solution was poured into water, extracted three times with dichloromethane and water, and then purified by column chromatography, using 200-300 mesh silica gel as the stationary phase, and the polarity of the eluent was petroleum ether/dichloromethane. (3:2) to give grey solid product in 88% yield. The results of ¹ H NMR, ¹³ CNMR, MS and elemental analysis indicated that the obtained compound was the target product.

(4) Preparation of compound 11

Under nitrogen protection, compound 10 (976 mg, 2.5 mmol) was dissolved in 120 mL of absolute ethanol, and then bis(2-thienyl)ethanedione (666 mg, 3.0 mmol) was added dropwise to the reaction system. Then 10 mg of p-toluenesulfonamide was added as a catalyst, and the reaction was carried out under reflux reaction conditions for 12 hours. After cooling, the reaction solution was poured into water, extracted three times with dichloromethane and water, and then purified by column chromatography, using 200-300 mesh silica gel as the stationary phase, and the polarity of the eluent was petroleum ether/chloroform (1 :1). Recrystallization from methanol gave a yellow solid product in 75% yield. The results of ¹ H NMR, ¹³ CNMR, MS and elemental analysis indicated that the obtained compound was the target product.

The chemical reaction equations for the synthesis of compounds 8 to 11 are as follows:

Example 3

Preparation of compound 12

Under nitrogen protection, compound 10 (976 mg, 2.5 mmol) was dissolved in 120 mL of anhydrous acetic acid, and diacetyl (451 mg, 5.24 mmol) was added dropwise to the reaction system. The reaction was carried out at 50°C for 12 hours. After cooling, the reaction solution was poured into water, extracted three times with dichloromethane and water, and then purified by column chromatography, using 200-300 mesh silica gel as the stationary phase, and the polarity of the eluent was petroleum ether/dichloromethane. (volume ratio of 2:3), finally a pale yellow solid product was obtained with a yield of 78%. The results of ¹ HNMR, ¹³ CNMR and elemental analysis indicated that the obtained compound was the target product.

Example 4

Preparation of compound 13

Under nitrogen protection, thiophene (4.21 g, 50 mmol) was dissolved in 250 mL of anhydrous tetrahydrofuran, cooled to -5 °C, n-butyllithium (8 mL, 200 mmol) was added dropwise, and the mixture was stirred at -5 °C for 2 hours. A solution of trimethyltin chloride in tetrahydrofuran (450 mL, 450 mmol) was injected, and the mixture was naturally warmed to room temperature to react for 12 hours. After the tetrahydrofuran was distilled off under reduced pressure, the product was extracted with dichloromethane, washed three times with deionized water, and the dichloromethane was spin-dried. Recrystallization from methanol gave the product as a white solid in 86% yield. The results of ¹ HNMR, ¹³ CNMR, MS and elemental analysis indicated that the obtained compound was the target product.

Example 5

Preparation of compound 15

(1) Preparation of compound 14

In a nitrogen atmosphere, under an ice bath, dithienocyclopentadiene (1.78 g, 10 mmol), sodium tert-butoxide (2.88 g, 30 mmol), and bromohexadecane (6.67 g, 22 mmol) were added to 100 mL of tetrahydrofuran, The reaction was stirred for 24 hours. THF was spin-dried under reduced pressure, extracted with dichloromethane, washed three times with saturated aqueous sodium chloride solution, and spin-dried with dichloromethane. The crude product was purified by column chromatography using petroleum ether as eluent to obtain a white solid product with a yield of 90%. The results of ¹ H NMR, ¹³ CNMR, MS and elemental analysis indicated that the obtained compound was the target product.

(2) Preparation of compound 15

Under nitrogen protection, compound 19 (3.14 g, 5 mmol) was dissolved in 150 mL of anhydrous tetrahydrofuran, cooled to -5 °C, n-butyllithium (8 mL, 20 mmol) was added dropwise, and the mixture was stirred at -5 °C for 2 hours. A solution of trimethyltin chloride in tetrahydrofuran (45 mL, 45 mmol) was injected, and the mixture was naturally warmed to room temperature to react for 12 hours. After the tetrahydrofuran was distilled off under reduced pressure, the product was extracted with dichloromethane, washed three times with deionized water, and the dichloromethane was spin-dried. Recrystallization from isopropanol gave the product as a white solid in 87% yield. The results of ¹ H NMR, ¹³ CNMR, MS and elemental analysis indicated that the obtained compound was the target product.

The chemical reaction equations for the synthesis of compounds 19-20 are as follows:

Example 6

Preparation of compound 17

(1) Preparation of compound 16

Under nitrogen protection, 3,3'-dibromo-2,2'-bithiophene (3.24g, 10mmol), 2-octyldodecylamine (3.57g, 12mmol) sodium tert-butoxide (2.40g, 25mmol), Tris(dibenzylideneacetone)dipalladium (0.46g, 0.5mmol), 2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl (0.62g, 1mmol) were added to 100mL of anhydrous toluene middle. After heating to 100°C for 12 hours, washing with saturated aqueous sodium chloride solution for 3 times, after spin-drying the solvent of the organic layer, the crude product was purified by column chromatography using petroleum ether as eluent to obtain a colorless oily product with a yield of 70%. %. The results of ¹ H NMR, ¹³ CNMR, MS and elemental analysis indicated that the obtained compound was the target product.

(2) Preparation of compound 17

The reaction and purification methods of compound 22 were similar to those of compound 20, and a light yellow oily product was obtained with a yield of 84%. The results of ¹ HNMR, ¹³ CNMR, MS and elemental analysis indicated that the obtained compound was the target product.

The chemical reaction equations for the synthesis of compounds 21 to 22 are shown below:

Example 7

Preparation of compound 20

(1) Preparation of compound 18

Under nitrogen protection, thiophene (8.41 g, 100 mmol) was dissolved in 100 mL of anhydrous tetrahydrofuran, cooled to -60 °C, n-butyllithium (40 mL, 100 mmol) was added dropwise, and then stirred at -60 °C for 2 hours. Then, bromoisooctane (19.31 g, 100 mmol) was added to the reaction system, and the reaction was naturally raised to room temperature for 12 hours. After removing tetrahydrofuran with a rotary evaporator, the product was extracted with petroleum ether, washed three times with deionized water, spin-dried with dichloromethane, and then further purified by vacuum distillation, with a yield of 48%. The results of ¹ H NMR, ¹³ CNMR, MS and elemental analysis indicated that the obtained compound was the target product.

(2) Preparation of compound 19

Under nitrogen protection, compound 18 (9.82 g, 50.0 mmol) was dissolved in 150 mL of anhydrous tetrahydrofuran, cooled to -10 °C, n-butyllithium (40 mL, 100 mmol) was added dropwise, and the temperature was naturally raised to room temperature at 55 °C. The oil bath was heated, and after 2 hours of reaction at 55 °C, the reaction system was placed in an ice bath, and benzo[1,2-b:4,5-b']dithiophene-4,8-dione (3.97 g, 18.0 mmol), then moved to room temperature and reacted for 20 minutes, tin dichloride (22.0 g, 116.1 mmol) was dissolved in 25 mL of concentrated hydrochloric acid, and added to the reaction system. It was then reacted at room temperature for 12 hours. The reaction solution was poured into ice water, extracted with dichloromethane, washed three times with saturated aqueous sodium chloride solution, and spin-dried with dichloromethane. Then, it was purified by column chromatography, using 200-300 mesh silica gel as the stationary phase, the polarity of the eluent was petroleum ether/dichloromethane (9:1), and finally a yellow solid product was obtained with a yield of 66%. The results of ¹ HNMR, ¹³ CNMR and elemental analysis indicated that the obtained compound was the target product.

(3) Preparation of compound 20

Under nitrogen protection, compound 19 (28.95 g, 50.0 mmol) was dissolved in 250 mL of anhydrous tetrahydrofuran, cooled to -10 °C, n-butyllithium (8 mL, 20 mmol) was added dropwise, and then stirred at -10 °C for 2 hours. A solution of trimethyltin chloride in tetrahydrofuran (45 mL, 45 mmol) was injected, and the mixture was naturally warmed to room temperature to react for 12 hours. After removing tetrahydrofuran by rotary evaporator, the product was extracted with dichloromethane, washed three times with deionized water, and then spin-dried in dichloromethane. First recrystallize with petroleum ether, then recrystallize with anhydrous alcohol, and then recrystallize with anhydrous ethanol to finally obtain a pale yellow solid with a yield of 75%. The results of ¹ H NMR, ¹³ CNMR, MS and elemental analysis indicated that the obtained compound was the target product.

Example 8

Preparation of polymer P1

Under nitrogen protection, compound 12 (88.24 mg, 0.2 mmol) and compound 19 (180.92 mg, 0.2 mmol) were dissolved in 4.4 mL of anhydrous chlorobenzene, and tetrakis(triphenylphosphine)palladium (8 mg) was added. The reaction was performed at 140°C for 24 hours, and the first capping was performed with 2-(tributyltin)thiophene (20 mg). After the reaction for 6 hours, the second capping was performed with 2-bromothiophene (30 mg), and the reaction was continued for 6 hours. . End the reaction, after the reaction is lowered to room temperature, the reaction solution is precipitated in methanol, and the polymer obtained by filtration is successively extracted with methanol, acetone, n-hexane, and chloroform through a Soxhlet extractor, and each extraction lasts 8 hours. . Finally, the solution obtained by chloroform extraction was concentrated, precipitated in methanol, filtered and dried to obtain a fibrous polymer. The results of ¹ H NMR and elemental analysis indicated that the obtained compound was the target product.

The chemical reaction equation for the synthesis of polymer P1 is shown below:

Example 9

Preparation of polymer P2

The reaction and purification methods of polymer P2 are similar to those of polymer P1, and the fibrous polymer is also obtained. The results of ¹ H NMR and elemental analysis indicated that the obtained compound was the target product. The reaction equation is as follows:

Example 10

Preparation of polymer P3

The reaction and purification methods of polymer P3 are similar to those of polymer P1, and a fibrous polymer is also obtained. The results of ¹ H NMR and elemental analysis indicated that the obtained compound was the target product.

The reaction equation is as follows:

Example 11

Preparation of polymer P4

Under nitrogen protection, compound 12 (88.24 mg, 0.2 mmol) and compound 17 (157.09 mg, 0.2 mmol) were dissolved in 4 mL of anhydrous o-dichlorobenzene, and tetrakis(triphenylphosphine)palladium (8 mg) was added. The reaction was carried out at 140°C for 48 hours, and the first capping was performed with 2-(tributyltin)thiophene (20 mg). After the reaction for 6 hours, the second capping was carried out with 2-bromothiophene (30 mg), and the reaction was continued for 6 hours. . End the reaction, after the reaction is lowered to room temperature, the reaction solution is precipitated in methanol, and the polymer obtained by filtration is successively extracted with methanol, acetone, n-hexane, and chloroform through a Soxhlet extractor, and each extraction lasts 8 hours. . Finally, the solution obtained by chloroform extraction was concentrated, precipitated in methanol, filtered and dried to obtain a fibrous polymer. The results of ¹ H NMR and elemental analysis indicated that the obtained compound was the target product.

The reaction equation is as follows:

Example 12

Preparation of polymer P5

In a nitrogen atmosphere, compound 12 (88.24 mg, 0.2 mmol), compound 15 (190.57 mg, 0.2 mmol), tris(dibenzylideneacetone)dipalladium (4 mg) and tris(o-methylphenyl)phosphorus (8 mg) were combined ) was dissolved in 3.6 mL of anhydrous chlorobenzene. The reaction was carried out at 140°C for 48 hours, and the first capping was performed with 2-(tributyltin)thiophene (20 mg). After the reaction for 6 hours, the second capping was carried out with 2-bromothiophene (30 mg), and the reaction was continued for 6 hours. After finishing the reaction, after the reaction was lowered to room temperature, the reaction solution was precipitated in methanol, the polymer obtained by filtration was subjected to Soxhlet extraction with methanol and acetone successively, and chloroform was used as the eluent to carry out column chromatography, and dried to obtain fibers shape polymer. The results of ¹ H NMR and elemental analysis indicated that the obtained compound was the target product.

The chemical reaction equation for the synthesis of polymer P5 is shown below:

Example 13

Preparation of polymer P6

The reaction and purification methods of polymer P6 are similar to those of polymer P5, and a fibrous polymer is also obtained. The results of ¹ H NMR and elemental analysis indicated that the obtained compound was the target product.

The reaction equation is as follows:

Example 14

Testing of Polymer Absorption Spectra

Fig. 1, Fig. 2, Fig. 3 are the ultraviolet-visible-near-infrared absorption spectra of the films of polymers P1, P3, and P6 on a quartz plate or in a chlorobenzene solution, respectively. It can be seen from FIG. 1 that P1 has absorption in a wide wavelength range of 300 to 900 nm. It can be seen from FIG. 2 that P3 has absorption in a wide wavelength range of 300 to 1000 nm. It can be seen from FIG. 3 that P3 has absorption in a wide wavelength range of 300 to 1200 nm. It can be seen from these three figures that polymers P1, P3, and P6 show a wide absorption range in both solution and film, and the absorption maximum absorption sideband values of the films are around 900 nm, 1000 nm, and 1200 nm, respectively.

Example 15

Fabrication of polymer solar cell devices

Take pre-made indium tin oxide (ITO) glass with a square resistance of 15Ω, ultrasonically clean it with acetone, detergent, deionized water and isopropanol in sequence, and treat with plasma for 10 minutes. A polyethoxythiophene (PEDOT:PSS) film doped with polystyrene sulfonic acid was spin-coated on ITO with a thickness of 40 nm. The PEDOT:PSS films were dried at 80°C for 8 hours in a nitrogen atmosphere glove box. The o-dichlorobenzene solution (1 wt. %) of polymer P1 and PC ₇₁ BM with a mass ratio of 1:1.5 was then spin-coated on the surface of the PEDOT:PSS film with a thickness of 100 nm. Then a 5 nm thick PFN-Br film was spin-coated on the active layer. Finally, a metal Al layer with a thickness of 100 nm was evaporated, and the device structure was ITO/PEDOT:PSS/P1:PC ₇₁ BM/PFN-Br/Al.

Polymer solar cells based on polymer P1 as electron donor material possess a broad absorption from 300 nm to 1000 nm, as shown in Figure 1. The photoelectric conversion efficiency of the device was tested under 1 natural light intensity through a standard simulated lamp system, and the photoelectric conversion efficiency (PCE) of the device was 5.1%, indicating good photoelectric conversion performance.

Example 16

Preparation of polymer photodetectors

Take pre-made indium tin oxide (ITO) glass with a square resistance of 15Ω, ultrasonically clean it with acetone, detergent, deionized water and isopropanol in sequence, and treat with plasma for 10 minutes. A polyethoxythiophene (PEDOT:PSS) film doped with polystyrene sulfonic acid was spin-coated on ITO with a thickness of 25 nm. The PEDOT:PSS films were dried at 80°C for 8 hours in a nitrogen atmosphere glove box. The chlorobenzene solution (1 wt. %) of polymer P3 and PC ₆₁ BM with a mass ratio of 1:1.2 was then spin-coated on the surface of the PEDOT:PSS film with a thickness of 100 nm. Then a 5 nm thick PFN-Br film was spin-coated on the active layer. Finally, a metal Al layer with a thickness of 100 nm was evaporated, and the device structure was ITO/PEDOT:PSS/P3:PC ₆₁ BM/PFN-Br/Al.

The polymer photodetector based on polymer P3 as the electron donor material has a wide response from 300nm to 1000nm, as shown in Figure 2, the current-voltage data of the device is obtained from a current-voltage source (Keithley 2400) at -2V to 2V The dark current J _d is as low as 2.5×10 ^-8 A/cm ² at a voltage of -0.1V, the curve is shown in Figure 4, and the detection rate at 850 nm wavelength can reach 1.09 ×10 ¹² Jones, it can be seen that the P3-based device has lower dark current and higher switching ratio. Its curve is shown in Figure 5, and it can be seen that the P3-based device has a response in a wide wavelength range and a high photodetection rate.

The above examples are only preferred embodiments of the present invention, and are only used to explain the present invention, but not to limit the present invention. Changes, substitutions, modifications, etc. made by those skilled in the art without departing from the spirit of the present invention shall belong to the present invention. the scope of protection of the invention.

Claims (10)

1. A donor-receptor type polymer containing a fused ring unit based on quinoxalinylbenzotriazole is characterized in that the chemical structural formula satisfies the following general formula:

wherein x and y are mole fractions of each unit, wherein 0< x <1, 0< y <1, and x + y is 1; n is the number of repeating units, n is an integer greater than 1;

R₁、R₂an alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 3 to 30 carbon atoms, an aromatic hydrocarbon group having 6 to 60 carbon atoms or an aromatic heterocyclic group having 3 to 60 carbon atoms;

ar is an aromatic hydrocarbon group having 6 to 100 carbon atoms or an aromatic heterocyclic group having 3 to 100 carbon atoms.

2. The quinoxalinylbenzotriazole-based fused ring unit-containing donor-acceptor type polymer according to claim 1, wherein said Ar unit is preferably one or more of the following structures or a halogenated, deuterated, alkyl-substituted derivative of the following structures:

wherein R is₃Is an alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 3 to 30 carbon atoms, an aromatic hydrocarbon group having 6 to 60 carbon atoms or an aromatic heterocyclic group having 3 to 60 carbon atoms.

3. A method for preparing a donor-receptor type polymer containing a fused ring unit based on quinoxalinylbenzotriazole according to claims 1-2, comprising the steps of:

(1) under the protection of inert gas, dissolving an Ar unit monomer containing a dialkyl tin functional group and an A unit monomer of a condensed ring unit based on quinoxalinylbenzotriazole in a solvent, then adding a catalyst to obtain a mixed solution, and heating to perform Stille polymerization reaction to obtain a mixture after polymerization reaction;

(2) after purifying the mixture in the step (1), obtaining the donor-receptor type polymer containing the fused ring unit based on the quinoxalinebenzenetriazole.

4. The method for producing a donor-acceptor-type polymer containing a condensed ring unit based on quinoxalinylbenzotriazole according to claim 3, wherein the solvent in the step (1) comprises at least one of toluene, tetrahydrofuran, xylene, chlorobenzene, dichlorobenzene; the catalyst is a Stille polymerization catalyst, and the catalyst comprises at least one of tetrakis (triphenylphosphine) palladium, tris (dibenzylideneacetone) dipalladium/tris (o-methylphenyl phosphine); the A unit monomer of the condensed ring unit based on the quinoxalinobenzotriazole is a double brominated A unit monomer of the condensed ring unit based on the quinoxalinobenzotriazole or a double iodo A unit monomer of the condensed ring unit based on the quinoxalinobenzotriazole; the dosage of the catalyst is 2 per mill-3% of the total mole amount of the reaction monomer; in the mixed solution, the molar amount of the Ar unit monomer containing the dialkyl tin functional group is equal to that of the A unit monomer based on the condensed ring unit of the quinoxalinobenzotriazole; the structural formula of the Ar unit monomer containing the dialkyl tin functional group is one of the following structural formulas:

R₃is alkyl with 1-30 carbon atoms, and 3-c30 cycloalkyl groups, aromatic hydrocarbon groups having 6 to 60 carbon atoms, or aromatic heterocyclic groups having 3 to 60 carbon atoms;

the structural general formula of the A unit monomer of the fused ring unit based on the quinoxalinobenzotriazole is shown as follows:

in the formula, R₁、R₂Each of which is an alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 3 to 30 carbon atoms, an aromatic hydrocarbon group having 6 to 60 carbon atoms or an aromatic heterocyclic group having 3 to 60 carbon atoms, and X is a bromine atom or an iodine atom.

5. The method for preparing a donor-acceptor-type polymer containing a condensed ring unit based on quinoxalinylbenzotriazole according to claim 3, wherein the temperature of the Stille polymerization reaction in the step (1) is 60 to 180 ℃ and the time of the Stille polymerization reaction is 0.5 to 72 hours.

6. The method for producing a donor-receptor-type polymer containing a condensed ring unit based on quinoxalinylbenzotriazole according to claim 3, wherein the purification in step (2) comprises: and cooling the mixture after the polymerization reaction to room temperature, dropwise adding the mixture into stirred methanol for precipitation, filtering and drying to obtain a crude product, extracting the crude product by using methanol and acetone in sequence, dissolving the crude product by using chlorobenzene, precipitating the crude product in a methanol solution again after concentration, filtering and drying to obtain the target product donor-receptor type polymer containing the fused ring unit based on the quinoxalinobenzo triazole.

7. The method for producing a donor-receptor-type polymer containing a condensed ring unit based on quinoxalinylbenzotriazole according to claim 3, characterized by comprising the steps of:

(1) under the protection of inert gas, dissolving an Ar unit monomer containing a dialkyl tin functional group and an A unit monomer of a condensed ring unit based on quinoxalinobenzotriazole in a solvent, and heating for Stille polymerization reaction to obtain a mixture; adding alkyl tin thiophene into the mixture to perform a first heat preservation reaction, then adding bromothiophene to perform a second heat preservation reaction to obtain a reaction solution;

(2) and (2) purifying the reaction solution obtained in the step (1) to obtain the donor-receptor type polymer containing the fused ring unit based on the quinoxalinebenzotriazole.

8. The method for preparing a donor-acceptor-type polymer containing a condensed ring unit based on quinoxalinylbenzotriazole according to claim 7, wherein the alkyl tin thiophene is used in an amount of 10 to 40% of the total molar amount of the reaction monomers; the dosage of the bromothiophene is 1-20 times of the molar weight of the alkyl tin thiophene; the time of the first heat preservation reaction is 6-12 hours; the time of the second heat preservation reaction is 6-12 hours.

9. Use of a quinoxalinylbenzotriazole based fused ring unit containing donor-acceptor type polymer according to any of claims 1-3 for the preparation of an electronic device comprising one or more of an organic/polymer photodetector, an organic/polymer solar cell, an organic/polymer thin film transistor, an organic/polymer light emitting transistor, an organic/polymer phototransistor, an organic/polymer organic light emitting electrochemical cell.

10. Use of a quinoxalinylbenzotriazole based fused ring unit containing donor-acceptor type polymer according to claim 9 for the preparation of electronic devices, characterized in that it comprises: dissolving the donor-receptor type polymer containing the fused ring unit based on the quinoxalinylbenzotriazole in an organic solvent, and then forming a film through spin coating, ink-jet printing or printing to obtain an active layer of the organic/polymer electronic device; the organic solvent comprises more than one of dimethylbenzene, tetrahydrofuran, chlorobenzene and dichlorobenzene.

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