CN111233898A - Organic small molecule conjugated material containing isotactic bipyridine thiadiazole receptor and preparation method and application thereof - Google Patents

Abstract

The invention discloses an organic small molecule conjugated material containing an isotactic bipyridine thiadiazole acceptor and a preparation method and application thereof. The organic small molecule conjugated material has the following formula (I), formula (II) or formula The structural formula shown in (III). The present invention uses 7-bromo-4-chloro[1,2,5]thiadiazole[3,4-c]pyridine as raw material for the first time, and adopts Stille coupling and other reactions to synthesize isotactic bipyridine thiadiazole receptors The organic small molecule conjugated material is provided, and a technical scheme for regulating the structural regularity and optoelectronic properties of the bipyridine thiadiazole-based organic small molecule conjugated material is provided. This type of organic small molecule conjugated material has the advantages of strong electricity absorption ability, large skeleton conjugate, good solubility, excellent thermal stability and strong light absorption ability. The preparation method is simple and efficient, with good repeatability and high universality, and can be promoted The development of more structured D-A-type organic conjugated materials has commercial prospects in the field of organic optoelectronics.

Description

An organic small molecule conjugated material containing isotactic bipyridine thiadiazole acceptors and its preparation Preparation method and application

technical field

The invention belongs to the field of organic optoelectronic functional materials, relates to an organic small molecule conjugated material used for organic field effect transistor devices and a method for regulating the regularity of its structure and its application, in particular to an organic small molecule conjugated material containing an isotactic bipyridine thiadiazole acceptor. Small molecule conjugated material and preparation method and application thereof.

Background technique

Compared with random organic conjugated materials, structurally regular organic conjugated materials have more ordered main chain skeleton structure, more prominent film assembly ability, wider film absorption and higher carrier mobility, etc. Advantage. In recent years, the control of structural regularity of organic conjugated materials and their applications in the field of organic electronics has received extensive attention. Earlier research found that by controlling the sequential structure of 3-alkylthiophenes into the polymer backbone, scientists developed poly(3-alkylthiophenes) with strict head-to-tail (H-T) linkages and discovered their ability to assemble thin films, Crystallinity, absorption spectrum, carrier mobility, and photovoltaic performance have all been significantly improved (J.Am.Chem.Soc., 1992, 114, 10087–10088; Nature., 1999, 401, 685–688; Nat.Mater. , 2006, 5, 197–203). Recently, the idea of structural regularity control has been further generalized for the design of D-A-type organic small molecules and polymer conjugated materials. For example, chemists introduced structurally asymmetric pyridinethiadiazole acceptor units into the main chain of D-A-type organic/polymer semiconductor materials, and developed a A series of D-A organic/polymer semiconductor materials with excellent comprehensive properties and regular structure (J.Am.Chem.Soc., 2011, 133, 18538–18541; Chem. Commun., 2013, 49, 7192–7194; J.Am Chem. Soc., 2014, 136, 12576-12579; J. Am. Chem. Soc., 2017, 139, 17735-17738). Although pyridinethiadiazole acceptor units are widely used in the synthesis of high-performance organic/polymer semiconductor materials, D-A-type organic small molecule conjugated materials containing isotactic bipyridinethiadiazole acceptors and their structural regularity control methods There is still no report, it is of great significance to develop such organic conjugated materials and explore the relationship between structural regularity and optoelectronic properties.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a class of organic small molecule conjugated materials containing isotactic bipyridine thiadiazole acceptors, and a preparation method and application thereof. The technical problem solved by the present invention is to provide a regularity regulation method for synthesizing a series of organic small molecule conjugated materials containing isotactic bipyridine thiadiazole acceptor units, for studying the relationship between molecular structure and its properties.

An organic small molecule conjugated material containing an isotactic bipyridyl thiadiazole acceptor, the organic small molecule conjugated material containing an isotactic bipyridine thiadiazole acceptor has the following formulas (I) and (II) Or the structural formula shown in formula (III):

In the formula (I), formula (II) or formula (III), Ar is one of the structural formulas shown in formula (IV) or formula (V),

In the formula (IV) or formula (V), R ₁ is selected from a C ₄ -C ₁₆ straight chain alkyl group, and R ₂ is selected from a C ₈ -C ₃₀ branched chain alkyl group.

Above-mentioned organic small molecule conjugated material containing isotactic bipyridine thiadiazole acceptor, preferably, described R ₁ is n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl , n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl or n-hexadecyl; the R ₂ is 2-ethyl Hexyl, 2-butylhexyl, 2-hexyloctyl, 4-hexyldecyl, 3-hexylundecyl, 2-octyldecyl, 2-octyldodecyl, 3-octyltridecyl Alkyl, 2-decyldodecyl, 2-decyltetradecyl, 3-decylpentadecyl, 2-dodecylhexadecyl, 4-octyltetradecyl, 4-decylhexadecyl, 4-hexyldecyl, 4-octyldodecyl, 4-decyltetradecyl or 4-dodecylhexadecyl.

The above-mentioned organic small molecule conjugated materials containing isotactic bipyridyl thiadiazole acceptors, preferably, the organic small molecule conjugated materials containing isotactic bipyridine thiadiazole acceptors are M1, M2, M3, M4 , M5 or M6, respectively corresponding to the structural formula shown in the following formula VI, formula VII, formula VIII, formula IX, formula X and formula XI:

As a general inventive concept, the present invention also provides a method for preparing the above-mentioned isotactic bipyridine thiadiazole acceptor-containing organic small molecule conjugated material, comprising the following steps:

(1) Under nitrogen protection, the aromatic compound intermediate Ar is converted into a lithium salt with butyllithium, and then tributyltin chloride is added to obtain the tributyltin alkyl aromatic compound intermediate formula (XII):

In the formula (XII), Ar is one of the structural formulas shown in formula (IV) or formula (V);

Wherein, the definitions of R ₁ and R ₂ are the same as the definitions of R ₁ and R ₂ in the above-mentioned products.

(2) Under nitrogen protection, tributylstannyl aromatic compound intermediate formula (XII) and 7-bromo-4-chloro[1,2,5]thiadiazo[3,4-c]pyridine were subjected to palladium-catalyzed Stille Coupling reaction to obtain intermediates a and b;

The structural formula of the intermediate a is:

The structural formula of the intermediate b is:

In described formula a or b, Ar is a kind of in the structural formula shown in formula (IV) or formula (V);

Wherein, the definitions of described R ₁ and R ₂ are the same as the definitions of R ₁ and R ₂ in the product;

(3) preparation formula (I): under nitrogen protection, Suzuki coupling reaction occurs with intermediate a and biboronic acid pinacol ester under palladium catalysis, obtains the target product formula (I) of pyridine N atom towards the outside simultaneously,

In the formula (I), Ar is one of the structures represented by the formula (IV) or the formula (V);

Wherein, the definitions of R ₁ and R ₂ are the same as the definitions of R ₁ and R ₂ in the product.

Alternatively, to prepare formula (II): under the protection of nitrogen, a Stille coupling reaction between intermediate b and 1,1,1,2,2,2-hexamethylditin is catalyzed by palladium to obtain a pyridine N atom at the same time towards the inner target product formula (II),

In the formula (II), Ar is one of the structures represented by the formula (IV) or the formula (V);

Wherein, the definitions of R ₁ and R ₂ are the same as the definitions of R ₁ and R ₂ in the product.

Or, to prepare formula (III): under nitrogen protection, the intermediate b is first reacted with 1,1,1,2,2,2-hexamethylditin under palladium catalysis for 1 hour, and then added at one time Intermediate a, continue to undergo Stille coupling reaction to obtain the target product formula (III) with the pyridine N atom facing the same side at the same time,

In the formula (III), Ar is one of the structures shown in the formula (IV) or the formula (V);

Wherein, the definitions of R ₁ and R ₂ are the same as the definitions of R ₁ and R ₂ in the product.

The above-mentioned preparation method of the organic small molecule conjugated material containing the isotactic bipyridine thiadiazole acceptor, preferably, the step (1) is specifically: under nitrogen protection, the aromatic compound intermediate (Ar) is mixed with a solvent , at -78 ℃, add n-butyllithium, react for 0.5 hours to 2 hours, then add tributyltin chloride, react at room temperature for 5 hours to 30 hours, extract with dichloromethane and saturated brine, separate the organic phase, After drying over anhydrous magnesium sulfate, after filtration, the solvent is removed by spinning to obtain the tributylstannyl aromatic intermediate represented by formula XII. The molar ratio of the aromatic compound intermediate (Ar), n-butyllithium and tributyltin chloride is 1.0:1.0-1.3:1.0-1.3.

The above-mentioned preparation method of the organic small molecule conjugated material containing isotactic bipyridine thiadiazole acceptor, preferably, the step (2) is specifically: under nitrogen protection, the tributyltin shown in formula (XII) Alkyl aromatic compound intermediate, 7-bromo-4-chloro[1,2,5]thiadiazole[3,4-c]pyridine, palladium catalyst and solvent are mixed, and stirred at 70～150℃ for 5～24 reactions h, extract with dichloromethane and saturated brine, separate the organic phase, dry over anhydrous magnesium sulfate, filter, and spin to remove the solvent to simultaneously obtain intermediate compound a and intermediate compound b, the intermediate compound shown in the formula (XII). The molar ratio of 7-bromo-4-chloro[1,2,5]thiadiazole[3,4-c]pyridine to the palladium catalyst is 1.0:1.0-1.5:0.005-0.2.

The above-mentioned preparation method of the organic small molecule conjugated material containing isotactic bipyridine thiadiazole acceptor, preferably, the preparation of formula (I) in the step (3) is specifically: under nitrogen protection, intermediate a, Biboronate pinacol ester, potassium acetate, palladium catalyst and solvent are mixed, and the reaction is stirred at 70 to 150 ° C for 5 to 24 hours. After the mixture solution is cooled to room temperature, it is extracted with dichloromethane and saturated brine, and the organic phase is separated. Dry over anhydrous magnesium sulfate, after filtration, spin to remove the solvent, and the crude product is purified by silica gel column chromatography to obtain the target product formula (I) with the pyridine N atom facing the outside at the same time, the intermediate a, pinacol biboronate, The molar ratio of potassium acetate to palladium catalyst is 1.0:1.0-2.0:1.0-3.0:0.005-0.2.

The above-mentioned preparation method of the organic small molecule conjugated material containing isotactic bipyridine thiadiazole acceptor, preferably, the preparation of formula (II) in the step (3) is specifically: under nitrogen protection, intermediate b, 1,1,1,2,2,2-Hexamethylditin, palladium catalyst and solvent are mixed, and the reaction is stirred at 70 to 150 ° C for 10 to 24 hours. After the mixture solution is cooled to room temperature, dichloromethane and Saturated brine extraction, separation of the organic phase, drying over anhydrous magnesium sulfate, after filtration, the solvent was removed by spinning, and the crude product was purified by silica gel column chromatography to obtain the target product formula (II) with the pyridine N atom facing the outside, the intermediate b. The molar ratio of 1,1,1,2,2,2-hexamethylditin to the palladium catalyst is 1.0:0.4-1.0:0.01-0.2.

The above-mentioned preparation method of the organic small molecule conjugated material containing the isotactic bipyridine thiadiazole acceptor, preferably, the preparation of the formula (III) in the step (3) is specifically: under nitrogen protection, intermediate b, Palladium catalyst, 1,1,1,2,2,2-hexamethylditin and solvent are mixed, and the reaction is stirred at 70～150℃ for 0.5 hour～2 hours, then intermediate a is added at one time, and the temperature is continued at 70～150℃. The reaction was stirred at 150°C for 3 to 24 hours. After the mixture solution was cooled to room temperature, it was extracted with dichloromethane and saturated brine, the organic phase was separated, dried over anhydrous magnesium sulfate, filtered, and the solvent was removed. Silica gel column chromatography was purified to obtain the target product formula (III) with the pyridine N atom facing the same side at the same time. The intermediate b, intermediate a, 1,1,1,2,2,2-hexamethylditin and The molar ratio of the palladium catalyst is 1.0:1.0:0.8-1.6:0.01-0.2.

The above-mentioned preparation method of the organic small molecule conjugated material containing isotactic bipyridine thiadiazole acceptor, preferably, the formula (IV) is mainly prepared by the following method: under the protection of nitrogen, thiophene is treated with butyllithium It is converted into thiophene lithium salt and then added with 1-bromoalkane to obtain the 2-alkylthiophene intermediate represented by formula (IV).

The above-mentioned preparation method of the organic small molecule conjugated material containing isotactic bipyridine thiadiazole acceptor, preferably, the formula (V) is mainly prepared by the following method:

(S1) under nitrogen protection, adopt nucleophilic substitution method to react 2-bromocarbazole with 1-bromoalkane to obtain 2-bromo-9-alkyl-substituted carbazole intermediate c;

The structural formula of the intermediate c is:

Wherein, the definition of described R ₂ is the same as the definition of R ₂ in the product;

(S2) Under nitrogen protection, using Stille coupling reaction, intermediate c is reacted with thiophenebutyltin reagent to obtain any one of the structures represented by formula (V).

The above-mentioned preparation method of the organic small molecule conjugated material containing isotactic bipyridine thiadiazole acceptor, preferably, the preparation process of the formula (IV) is specifically: under nitrogen protection, mix thiophene and solvent, -78 Add n-butyllithium at ℃, react for 1.5 to 2 hours, then add 1-bromoalkane, react overnight, extract with dichloromethane and saturated brine, separate the organic phase, dry over anhydrous magnesium sulfate, filter, spin The solvent is removed to obtain the 2-alkylthiophene intermediate represented by formula (IV); the molar ratio of the thiophene, n-butyllithium and 1-bromoalkane is 1.0:1.0-1.3:1.0-1.3.

The above-mentioned preparation method of the organic small molecule conjugated material containing isotactic bipyridine thiadiazole acceptor, preferably, in the preparation process of the formula (V), the (S1) is specifically: under nitrogen protection, the 2-Bromocarbazole, 1-bromoalkane, sodium hydride and solvent are mixed, stirred and reacted at 50～150℃ for 5～24 hours, extracted with dichloromethane and saturated brine, separated organic phase, dried over anhydrous magnesium sulfate , after filtration, the solvent is removed by spinning to obtain 2-bromo-9-alkyl-substituted carbazole intermediate c; the molar ratio of the 2-bromocarbazole, 1-bromoalkane and sodium hydride is 1.0:1.0～3.0 : 1.0～3.0;

The (S2) is specifically: under nitrogen protection, mixing 2-bromo-9-alkyl-substituted carbazole intermediate c, thiophenebutyltin reagent, palladium catalyst and solvent, and stirring at 70-150° C. for 5-24 reactions h, extracted with dichloromethane and saturated brine, separated the organic phase, dried over anhydrous magnesium sulfate, filtered, and removed the solvent to obtain any compound in the structure shown in formula (V); the 2-bromo- The molar ratio of the 9-alkyl-substituted carbazole intermediate c, the thiophenebutyltin reagent and the palladium catalyst is 1.0:1.0-3.0:0.01-0.2.

The preparation method of the above-mentioned organic small molecule conjugated material containing isotactic bipyridine thiadiazole acceptors, preferably, the palladium catalyst is selected from tetrakis (triphenylphosphine) palladium, bis (triphenylphosphine) dichloride at least one of palladium, palladium acetate and tris(dibenzylideneacetone)dipalladium.

The above-mentioned preparation method of the organic small molecule conjugated material containing isotactic bipyridine thiadiazole acceptor, preferably, the solvent is selected from toluene, xylene, trimethylbenzene, N,N'-dimethylformamide, N,N'-dimethylacetamide, N-methylpyrrolidone, chlorobenzene, dichlorobenzene, trichlorobenzene, 1,4-dioxane, tetrahydrofuran, acetonitrile and 1,4-dioxane at least one of.

As a general inventive concept, the present invention also provides the above-mentioned isotactic bipyridylthiadiazole acceptor-containing organic small molecule conjugated material or the above-mentioned preparation method containing isotactic bipyridinethiadiazole acceptor. The application of organic small molecule conjugated materials in the preparation of organic thin film field effect transistor devices.

For the above application, preferably, the application method is: first, the organic small molecule conjugated material containing the isotactic bipyridine thiadiazole acceptor is dissolved in a chloroform solution, and the obtained solution is spin-coated on a glass substrate A layer of organic semiconductor active layer film is obtained on the surface; secondly, a butyl acetate solution of polymethyl methacrylate is spin-coated on the surface of the organic semiconductor active layer film to obtain a polymethyl methacrylate dielectric layer; finally, a polymethyl methacrylate dielectric layer is obtained on the surface of the organic semiconductor active layer film A layer of aluminum is evaporated on the polymethyl methacrylate dielectric layer as a gate electrode.

The invention provides an organic small molecule conjugated material containing an isotactic bipyridine thiadiazole acceptor, aiming to regulate the orientation of the pyridine N atom on the bipyridyl thiadiazole acceptor, obtain three isomers, and study the molecular structure of the material. The effect of the difference on its optoelectronic properties. The main design ideas are as follows: 1) Compared with the single pyridinethiadiazole electron acceptor, the bipyridylthiadiazole electron acceptor has stronger power-deficient ability. Improve the electron affinity of the target molecule and tune the energy level and spectral absorption of the material. Therefore, it overcomes the shortcomings of weak charge-absorbing ability and small skeleton conjugation of the monopyridine thiadiazole acceptor unit; 2) By controlling the relative position of pyridine N on pyridine thiadiazole, three different orientations of pyridine N can be obtained. The isomer of the organic small molecule conjugated material of the regular bipyridine thiadiazole acceptor is easy to control the optoelectronic properties of the material; 3) By changing the terminal substitution end group, by introducing carboxylate with strong charge-donating property and good coplanarity The azole group can enhance the degree of conjugation of the molecule and facilitate the adjustment of the optoelectronic properties of the material.

Compared with the prior art, the advantages of the present invention are:

1. The synthetic technical route of the present invention has the advantages of simplicity and high efficiency, readily available raw materials, low cost and strong universality. It is suitable for scale-up synthesis and batch preparation, and can be popularized and developed for isotactic double-acceptor organic conjugated materials with strong electricity absorption ability, large skeleton conjugation, good solubility, excellent thermal stability and strong light absorption ability.

2. The target organic conjugated small molecule material of the present invention has the advantages of large skeleton conjugation and high content of heteroatoms, thus improving the intermolecular assembly ability.

3. The target organic conjugated small molecule material of the present invention contains a bipyridine thiadiazole acceptor unit with strong electricity-deficient ability and a thiophene/carbazole derivative donor unit with strong electricity-donating ability to enhance the charge in the molecule transfer, thus broadening the absorption and fluorescence spectra of the material.

4. By precisely controlling the orientation of pyridine N on pyridinethiadiazole, three kinds of organic small molecule conjugated materials containing isotactic bipyridinethiadiazole acceptors were developed, and the optoelectronic properties of the materials were successfully regulated.

5. The present invention provides the application of an organic small molecule conjugated material containing an isotactic bipyridine thiadiazole acceptor, and the organic small molecule conjugated material M4 is used in an organic thin film field effect transistor device, and obtains up to The hole mobility of 0.05 cm ² /V s fully demonstrates the commercial application prospects of this type of organic small molecule conjugated materials in the fields of organic field effect transistors, organic photovoltaics, organic photodetectors, and bioluminescence imaging.

Description of drawings

FIG. 1 is a ¹ H- ¹ H NOE spectrum of the organic small molecule conjugated material M1 containing an isotactic bipyridine thiadiazole acceptor in Example 1 with a mixing time of 0.3 s.

FIG. 2 is a ¹ H- ¹ H NOE spectrum of the organic small molecule conjugated material M1 containing an isotactic bipyridine thiadiazole acceptor in Example 1 with a mixing time of 0.8 s.

FIG. 3 is a ¹ H- ¹ H NOE spectrum of the organic small molecule conjugated material M2 containing an isotactic bipyridine thiadiazole acceptor in Example 2 with a mixing time of 0.3 s.

4 is a ¹ H- ¹ H NOE spectrum of the organic small molecule conjugated material M2 containing isotactic bipyridine thiadiazole acceptors in Example 2 with a mixing time of 0.8 s.

5 is the ¹ H- ¹ H NOE spectrum of the organic small molecule conjugated material M3 containing the isotactic bipyridine thiadiazole acceptor in Example 3 when the mixing time is 0.3 s.

6 is a ¹ H- ¹ H NOE spectrum of the organic small molecule conjugated material M3 containing an isotactic bipyridine thiadiazole acceptor in Example 3 with a mixing time of 0.8 s.

FIG. 7 is a ¹ H- ¹ H NOE spectrum of the organic small molecule conjugated material M4 containing an isotactic bipyridine thiadiazole acceptor in Example 4 with a mixing time of 0.3 s.

8 is a ¹ H- ¹ H NOE spectrum of the organic small molecule conjugated material M4 containing isotactic bipyridine thiadiazole acceptors in Example 4 with a mixing time of 0.8 s.

9 is a ¹ H- ¹ H NOE spectrum of the organic small molecule conjugated material M5 containing an isotactic bipyridine thiadiazole acceptor in Example 5 with a mixing time of 0.3 s.

10 is the ¹ H- ¹ H NOE spectrum of the organic small molecule conjugated material M5 containing the isotactic bipyridine thiadiazole acceptor in Example 5 when the mixing time is 0.8 s.

11 is the ¹ H- ¹ H NOE spectrum of the organic small molecule conjugated material M6 containing the isotactic bipyridine thiadiazole acceptor in Example 6 when the mixing time is 0.3 s.

12 is the ¹ H- ¹ H NOE spectrum of the organic small molecule conjugated material M6 containing isotactic bipyridine thiadiazole acceptors in Example 6 with a mixing time of 0.8 s.

Figure 13 shows the ultraviolet-visible-near-infrared absorption spectra of three organic small molecule conjugated materials M1, M2 and M3 containing isotactic bipyridine thiadiazole acceptors in chloroform solution.

Figure 14 shows the ultraviolet-visible-near-infrared absorption spectra of three organic small molecule conjugated materials M1, M2 and M3 containing isotactic bipyridine thiadiazole acceptors in the thin film state.

Figure 15 shows the ultraviolet-visible-near-infrared absorption spectra of three organic small molecule conjugated materials M4, M5 and M6 containing isotactic bipyridine thiadiazole acceptors in chloroform solution.

Figure 16 shows the ultraviolet-visible-near-infrared absorption spectra of three organic small molecule conjugated materials M4, M5 and M6 containing isotactic bipyridine thiadiazole acceptors in the thin film state.

Figure 17 is the molar extinction coefficient spectra of three organic small molecule conjugated materials M1, M2 and M3 containing isotactic bipyridine thiadiazole acceptors.

Figure 18 is the molar extinction coefficient spectra of three organic small molecule conjugated materials M4, M5 and M6 containing isotactic bipyridine thiadiazole acceptors.

Fig. 19 is the fluorescence spectra of three organic small molecule conjugated materials M1, M2 and M3 containing isotactic bipyridine thiadiazole acceptors in the state of chloroform solution.

Figure 20 is the fluorescence spectra of three organic small molecule conjugated materials M4, M5 and M6 containing isotactic bipyridine thiadiazole acceptors in the state of chloroform solution.

Figure 21 shows the cyclic voltammetry curves of three organic small molecule conjugated materials M1, M2 and M3 containing isotactic bipyridine thiadiazole acceptors measured in chloroform solution.

Figure 22 shows the cyclic voltammetry curves of three organic small molecule conjugated materials M4, M5 and M6 containing isotactic bipyridine thiadiazole acceptors measured in chloroform solution.

23 is a schematic structural diagram of a FET device using an organic small molecule conjugated material M4 containing an isotactic bipyridine thiadiazole acceptor as an organic active semiconductor layer in Example 4 of the present invention.

24 is an output characteristic curve diagram of a FET device using the organic small molecule conjugated material M4 containing an isotactic bipyridine thiadiazole acceptor as the organic active semiconductor layer in Example 4 of the present invention.

FIG. 25 is a transfer characteristic curve diagram of a FET device using an organic small molecule conjugated material M4 containing an isotactic bipyridine thiadiazole acceptor as an organic active semiconductor layer in Example 4 of the present invention.

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and specific preferred embodiments, but the protection scope of the present invention is not limited thereby. The examples described below are intended to facilitate the understanding of the present invention without any limitation thereto. The methods are conventional methods unless otherwise specified. The reaction materials can be purchased from open commercial sources unless otherwise specified.

Example 1:

An organic small molecule conjugated material containing an isotactic bipyridine thiadiazole acceptor of the present invention, denoted as M1, has the general structural formula of formula (I):

R₁为正丁基。Among them, Ar is

R ₁ is n-butyl.

The specific structural formula of M1 is:

A synthetic route of the organic small molecule conjugated material M1 containing isotactic bipyridine thiadiazole acceptors of the present embodiment is:

Specifically include the following steps:

(1) Synthesis of 2-butylthiophene: synthesis by the method reported in the reference (J.Am.Chem.Soc.2006,128,2336);

(2) Synthesis of 2-tributylstannyl-5-butylthiophene: synthesis by the method reported in the reference (Org.Lett.2008,10,3665);

(3) Synthesis of intermediates a and b: under nitrogen protection, add 600 mg of 7-bromo-4-chloro-[1,2,5]thiadiazole-[3,4-c]pyridine to a two-necked flask (2.4 mmol), 1.095 g of 2-tributylstannyl-5-butylthiophene (2.4 mmol), bis(triphenylphosphine)palladium dichloride (0.03 mmol) and 15 mL of toluene solvent. After stirring at 105°C for 8 hours, it was cooled to room temperature. The organic phase was extracted with dichloromethane and saturated brine, dried over anhydrous magnesium sulfate, and the solvent was spin-dried to obtain a crude product. Purified by silica gel column (eluent: petroleum ether: dichloromethane = 4: 1, V: V) to obtain 322 mg of yellow solid, intermediate a (yield = 38%), 223 mg of orange solid, intermediate b ( Yield = 30%).

The structural representation data is as follows:

Intermediate a: ¹ H NMR (400 MHz, CDCl ₃ ), δ (ppm): 8.61 (s, 1H), 8.50 (d, 1H), 6.94 (d, 1H), 2.90 (t, 2H), 1.77-1.73 (m, 2H), 1.44 (dd, 2H), 0.96 (t, 3H). ¹³ C NMR (100 MHz, CDCl ₃ ), δ (ppm): 156.26, 153.12, 147.86, 147.57, 145.78, 138.15, 133.14, 126.58 , 107.48, 33.47, 30.26, 22.18, 13.82. HRMS: m/z[M] ⁺ calcd for(C ₁₃ H ₁₂ BrN ₃ S ₂ ): 352.9656; found: 352.9652.

From the above, it can be seen that the structure of this compound is correct, and it is shown as intermediate a.

Intermediate b: ¹ H NMR (400 MHz, CDCl ₃ ), δ (ppm): 8.57 (s, 1H), 7.94 (d, 1H), 6.91 (d, 1H), 2.90 (t, 2H), 1.76-1.72 (m, 2H), 1.45 (dd, 2H), 0.97 (t, 3H). ¹³ C NMR (100 MHz, CDCl ₃ ), δ (ppm): 154.83, 149.52, 148.79, 142.64, 138.90, 132.35, 129.02, 125.58 , 122.69, 33.66, 29.98, 22.21, 13.82. HRMS: m/z[M] ⁺ calcd for(C ₁₃ H ₁₂ ClN ₃ S ₂ ): 309.0161; found: 309.0162.

From the above, it can be seen that the structure of this compound is correct, and it is shown as intermediate b.

(4) Synthesis of target product M1: under nitrogen protection, add 500 mg of intermediate a (1.4 mmol), 358.5 mg of biboronic acid pinacol ester (1.4 mmol), 412.5 mg of potassium acetate (4.2 mmol) to the two-necked flask mmol), bis(triphenylphosphine)palladium dichloride (0.01 mmol) and 20 mL of 1,4-dioxane solvent. After stirring at 80°C for 8 hours, the organic phase was extracted with dichloromethane and saturated brine, dried over anhydrous magnesium sulfate, and the solvent was spin-dried to obtain a crude product. Purified by silica gel chromatography (eluent: petroleum ether:dichloromethane=4:1, V:V) to obtain 329 mg of dark red solid, the target product M1 (yield=85%).

The structural representation data is as follows:

¹ H NMR (400 MHz, CDCl ₃ ), δ (ppm): 9.37 (s, 2H), 8.60 (d, 2H), 6.98 (d, 2H), 2.94 (t, 4H), 1.80–1.76 (m, 4H) ), 1.49–1.46 (m, 4H), 1.00–0.96 (t, 6H). ¹³ C NMR (100MHz, CDCl ₃ ), δ (ppm): 156.10, 153.03, 148.10, 148.01, 145.87, 139.04, 133.12, 126.55 , 119.54, 33.52, 30.31, 22.24, 13.85. HRMS: m/z[M] ⁺ calcd for(C ₂₆ H ₂₄ N ₆ S ₄ ): 549.1018; found: 549.1018.

It can be seen from the above that the structure of this compound is correct, and it is the target product M1 shown.

Example 2:

An organic small molecule conjugated material containing isotactic bipyridine thiadiazole acceptors of the present invention, denoted as M2, has the general structural formula of formula (II):

R₁为正丁基。Among them, Ar is

R ₁ is n-butyl.

The specific structural formula of M2 is:

A synthetic route of the organic small molecule conjugated material M2 containing isotactic bipyridine thiadiazole acceptors of the present embodiment is:

The synthetic methods of steps (1), (2) and (3) are the same as in Example 1.

(4) Synthesis of target product M2: under nitrogen protection, 200 mg of intermediate b (0.65 mmol) and 141 mg of 1,1,1,2,2,2-hexamethylditin (0.43 mg) were added to the two-necked flask. mmol), bis(triphenylphosphine)palladium dichloride (0.06 mmol) and 7 mL of toluene solvent. After stirring at 110°C for 15 hours, the organic phase was extracted with dichloromethane and saturated brine, dried over anhydrous magnesium sulfate, and the solvent was spin-dried to obtain a crude product. Purified by silica gel chromatography (eluent: petroleum ether: dichloromethane=1:1, V:V) to obtain 66 mg of orange solid, the target product M2 (yield=37%).

The structural representation data is as follows:

¹ H NMR (400 MHz, CDCl ₃ ), δ (ppm): 9.16 (s, 2H), 8.12 (d, 2H), 6.96 (d, 2H), 2.94 (t, 4H), 1.80–1.76 (m, 4H) ), 1.47(dd, 4H), 0.99(t, 6H). ¹³ C NMR (100MHz, CDCl ₃ ), δ(ppm): 155.04, 150.32, 150.06, 147.69, 139.84, 133.46, 129.70, 125.79, 123.46, 33.69 , 30.10, 22.27, 13.84. HRMS: m/z[M] ⁺ calcd for(C ₂₆ H ₂₄ N ₆ S ₄ ): 549.1018; found: 549.1019.

From the above, it can be seen that the structure of this compound is correct, and it is the target product M2 shown.

Example 3:

An organic small molecule conjugated material containing an isotactic bipyridine thiadiazole acceptor of the present invention, denoted as M3, has the general structural formula of formula (III):

R₁为正丁基。Among them, Ar is

R ₁ is n-butyl.

The specific structural formula of M3 is:

A synthetic route of the organic small molecule conjugated material M3 containing isotactic bipyridine thiadiazole acceptors of the present embodiment is:

The synthetic methods of steps (1), (2) and (3) are the same as in Example 1.

(4) Synthesis of target product M3: under nitrogen protection, 200 mg of intermediate b (0.56 mmol), 246 mg of 1,1,1,2,2,2-hexamethyldistin and ( 0.75 mmol), bis(triphenylphosphine) palladium dichloride (0.03 mmol) and 8 mL of toluene solvent, and after stirring at 110 ° C for 1 hour, 174 mg of intermediate a (0.56 mmol) was added at one time, and continued at 110 After stirring at °C for 24 hours, the organic phase was extracted with dichloromethane and saturated brine, dried over anhydrous magnesium sulfate, and the solvent was spin-dried to obtain a crude product. Purified by silica gel column (eluent: petroleum ether: dichloromethane = 1: 1, V: V) to obtain 130 mg of orange-red solid, the target product M3 (yield = 42%).

The structural representation data is as follows:

¹ H NMR (400MHz, CDCl ₃ ), δ(ppm): 9.49(s,1H), 9.13(s,1H), 8.68(d,1H), 8.06(d,1H), 7.01(d,1H), 6.95 (d, 1H), 2.94 (q, 4H), 1.78 (d, 4H), 1.47 (dd, 4H), 0.98 (td, 6H). ¹³ CNMR (100 MHz, CDCl ₃ ), δ (ppm): 155.97 ,154.76,153.95,150.13,149.57,149.28,148.44,147.69,147.45,140.38,139.03,133.91,133.54,129.02,126.77,125.61,122.11,121.64,33.69,33.53,30.36,30.07,22.29,22.23,13.95,13.84 .HRMS: m/z[M] ⁺ calcd for (C ₂₆ H ₂₄ N ₆ S ₄ ): 549.1018; found: 549.1019.

It can be seen from the above that the structure of this compound is correct, and it is the target product M3 shown.

Example 4:

An organic small molecule conjugated material containing isotactic bipyridine thiadiazole acceptors of the present invention, denoted as M4, has the general structural formula of formula (I):

R₂为2-癸基十四烷基。Among them, Ar is

R ₂ is 2-decyltetradecyl.

The specific structural formula of M4 is:

A synthetic route of the organic small molecule conjugated material M4 containing isotactic bipyridine thiadiazole acceptors of the present embodiment is:

Specifically include the following steps:

(1) Synthesis of compound c: synthesized by the method reported in the reference (New J.Chem.2018, 42, 2750);

(2) Synthesis of compound d: under nitrogen protection, 5.3g of 2-bromo-9-(2-decyltetradecyl)carbazole (9.1mmol), 3.78g of 2-tris Butyltinyl-thiophene (9.1 mmol), bis(triphenylphosphine)palladium dichloride (0.06 mmol) and 15 mL of toluene solvent. After stirring at 105°C for 8 hours, it was cooled to room temperature. The organic phase was extracted with dichloromethane and saturated brine, dried over anhydrous magnesium sulfate, and the solvent was spin-dried to obtain a crude product. Purified by silica gel column (eluent is petroleum ether) to obtain 4.1 g of white solid, intermediate d (yield=77%).

The structural representation data is as follows:

¹ H NMR (400 MHz, CDCl ₃ ), δ (ppm): 8.07 (dd, 2H), 7.59 (s, 1H), 7.50 (dd, 1H), 7.45 (t, 1H), 7.40–7.37 (m, 2H) ), 7.30–7.29(m, 1H), 7.22(t, 1H), 7.12(dd, 1H), 4.18(d, 2H), 2.15(s, 1H), 1.38–1.21(m, 40H), 0.88( dd, 6H). ¹³ C NMR (100MHz, CDCl ₃ ), δ (ppm): 145.79, 141.52, 141.32, 131.95, 128.05, 125.66, 124.47, 122.90, 122.61, 122.31, 120.61, 120.25, 118.936, 117.44 106.28, 47.62, 37.92, 31.94, 31.92, 29.98, 29.69, 29.64, 29.40, 29.37, 26.63, 22.73, 14.17. HRMS: m/z[M] ⁺ calcd for (C ₄₀ H ₅₉ NS): 585.4362; found: 585.4364 .

From the above, it can be seen that the compound has the correct structure and is the intermediate d shown.

(3) Synthesis of intermediate e: Under nitrogen protection, 4 g of intermediate d (6.8 mmol) and 50 mL of ultra-dry tetrahydrofuran solvent were added to a 250 mL three-necked flask. After cooling the solution to -78 °C, n-butyllithium in n-hexane solution (2.9 mL, 7.14 mmol) was added dropwise, and the solution was stirred at -78 °C for 1.5 h. After warming to room temperature and stirring for 30 min, the reaction mixture was cooled again to -78°C. Then, tributyltin chloride (2.16 mL, 7.48 mmol) was added in one portion, and the temperature was raised to room temperature and stirred for 12 hours. Extracted with dichloromethane and saturated brine, dried over anhydrous magnesium sulfate, filtered, and spun off to remove the solvent to obtain intermediate e (5.4 g, 90%), which was directly used in the next reaction without purification.

(4) Synthesis of intermediates a' and b': under nitrogen protection, add 300 mg of 7-bromo-4-chloro-[1,2,5]thiadiazole-[3,4-c to a two-necked flask ]pyridine (1.2 mmol), 996 mg of intermediate e (1.2 mmol), bis(triphenylphosphine)palladium dichloride (0.01 mmol) and 15 mL of toluene solvent. After stirring at 105°C for 6 hours, it was cooled to room temperature. The organic phase was extracted with dichloromethane and saturated brine, the organic phase was separated, dried over anhydrous magnesium sulfate, and the solvent was spin-dried to obtain a crude product. Purified by silica gel column (eluent: petroleum ether: dichloromethane = 4: 1, V: V), 345 mg of dark red solid was obtained as intermediate a' (yield = 36%), 299 mg of bright red solid was Intermediate b' (yield = 33%).

The structural representation data is as follows:

Intermediate a': ¹ H NMR (400 MHz, CDCl ₃ ), δ (ppm): 8.71 (d, 1H), 8.67 (s, 1H), 8.10 (t, 2H), 7.73 (s, 1H), 7.62 ( dd, 1H), 7.56(d, 1H), 7.47(t, 1H), 7.39(d, 1H), 7.24(d, 1H), 4.20(d, 2H), 2.17(s, 1H), 1.39–1.20 (m, 40H), 0.98–0.83 (m, 6H). ¹³ C NMR (100 MHz, CDCl ₃ ), δ (ppm): 156.30, 151.49, 147.91, 147.32, 145.81, 141.60, 141.24, 139.35, 134.14, 131.00, 126.06,124.83,123.23,122.45,120.73,120.38,119.16,117.22,109.13,107.75,106.43,47.68,37.86,31.92,31.87,29.98,29.68,29.63,29.36,26.60,22.68,14.12.HRMS:m/z[ M] ⁺ calcdfor(C ₄₅ H ₅₉ BrN ₄ S ₂ ): 798.3359; found: 798.3361.

From the above, it can be seen that the structure of this compound is correct, and it is the intermediate a' shown.

Intermediate b': ¹ H NMR (400 MHz, CDCl ₃ ), δ (ppm): 8.69 (s, 1H), 8.18 (d, 1H), 8.12-8.09 (m, 2H), 7.68 (s, 1H), 7.59(d,1H),7.52(d,1H),7.47(d,1H),7.40(d,1H),7.25(s,1H),4.22(d,2H),2.17(s,1H),1.40 -1.20 (m, 40H), 0.85 (dd, 6H). ¹³ C NMR (100 MHz, CDCl ₃ ), δ (ppm): 154.75, 149.04, 148.85, 148.51, 142.93, 141.61, 141.25, 138.98, 133.76, 130.99, 130.25,125.99,124.05,122.99,122.47,120.76,120.36,119.15,117.28,109.12,106.21,47.62,37.92,31.90,29.97,29.64,29.35,22.3,14.68HRMS, ⁺ calcd for (C ₄₅ H ₅₉ ClN ₄ S ₂ ): 754.3864; found: 754.3863.

From the above, it can be seen that the structure of this compound is correct, and it is the intermediate b' shown.

(5) Synthesis of target product M4: under nitrogen protection, 230 mg of intermediate a' (0.29 mmol), 75.5 mg of biboronic acid pinacol ester (0.29 mmol), 88 mg of potassium acetate (0.87 mmol) were added to the two-necked flask mmol), bis(triphenylphosphine)palladium dichloride (0.03 mmol) and 8 mL of 1,4-dioxane solvent. After stirring at 80° C. for 8 hours, extract with dichloromethane and saturated brine, dry over anhydrous magnesium sulfate, and spin dry the solvent to obtain a crude product. Purified by silica gel chromatography (eluent: petroleum ether: dichloromethane = 4: 1, V: V) to obtain 176 mg of purple-black solid, the target product M4 (yield = 85%).

The structural representation data is as follows:

¹ H NMR (400MHz, CDCl ₃ ), δ(ppm): 9.55(s, 2H), 8.56(d, 2H), 8.04(t, 4H), 7.62(s, 2H), 7.54(d, 2H), 7.43–7.41(m, 4H), 7.32(d, 2H), 7.21(t, 2H), 4.12(d, 4H), 2.13(s, 2H), 1.39–1.21(m, 80H), 0.85(td, 12H). ¹³ C NMR (100MHz, CDCl ₃ ), δ (ppm): 155.94, 151.23, 148.16, 147.54, 146.08, 141.61, 141.22, 140.24, 134.01, 131.11, 125.99, 124.77, 123.13, 120.77, 123.13, 120.650 _{119.67,119.11,117.22,109.15,106.30,47.70,37.89,31.93,30.01,29.66,29.64,29.37,29.36,26.64,22.69,14.13.HRMS} :m/z[M] ⁺ calcd for(C ₉₀ H ₁₁₈ S4): _1438.8356 ; found: 1438.8368.

It can be seen from the above that the structure of this compound is correct, and it is the target product M4 shown.

Example 5:

An organic small molecule conjugated material containing an isotactic bipyridine thiadiazole acceptor of the present invention, denoted as M5, has the general structural formula of formula (II):

R₂为2-癸基十四烷基。Among them, Ar is

R ₂ is 2-decyltetradecyl.

The specific structural formula of M5 is:

A synthetic route of the organic small molecule conjugated material M5 containing isotactic bipyridine thiadiazole acceptors of the present embodiment is:

The synthetic methods of steps (1), (2) and (3) are the same as in Example 4.

(4) Synthesis of target product M5: under nitrogen protection, add 200 mg of intermediate b' (0.26 mmol) and 57.8 mg of 1,1,1,2,2,2-hexamethyldistin to a two-necked flask (0.18 mmol), bis(triphenylphosphine)palladium dichloride (0.03 mmol) and 7 mL of toluene solvent. After stirring at 110°C for 24 hours, the organic phase was extracted with dichloromethane and saturated brine, dried over anhydrous magnesium sulfate, and the solvent was spin-dried to obtain a crude product. Purified by silica gel chromatography (eluent: petroleum ether: dichloromethane = 1: 1, V: V) to obtain 76.2 mg of purple solid, the target product M5 (yield = 40%).

The structural representation data is as follows:

¹ H NMR (400MHz, CDCl ₃ ), δ(ppm): 9.30(s, 2H), 8.33(d, 2H), 8.11(t, 4H), 7.71(s, 2H), 7.62(d, 2H), 7.57(d, 2H), 7.48(t, 2H), 7.40(d, 2H), 7.27(s, 0.33H), 7.24(d, 0.66H), 4.23(d, 4H), 2.19(s, 2H) , 1.42–1.21 (m, 80H), 0.85 (td, 12H). ¹³ C NMR (100MHz, CDCl ₃ ), δ (ppm): 154.94, 150.04, 149.25, 147.67, 141.64, 141.24, 139.87, 134.87, 131.09, 130.76,125.97,124.22,123.10,123.02,122.51,120.72,120.38,119.12,117.38,109.13,106.18,47.65,37.96,31.92,29.99,29.68,29.65,29.62,29.36,29.34,26.63,22.68,14.12.HRMS: m/z[M] ⁺ calcd for (C ₉₀ H ₁₁₈ N ₈ S ₄ ): 1439.8435; found: 1439.8441.

It can be seen from the above that the structure of this compound is correct, and it is the target product M5 shown.

Example 6:

A class of organic small molecule conjugated materials containing isotactic bipyridine thiadiazole acceptors of the present invention, denoted as M6, has the general structural formula of formula (III):

R₂为2-癸基十四烷基。Among them, Ar is

R ₂ is 2-decyltetradecyl.

The specific structural formula of M6 is:

A synthetic route of the organic small molecule conjugated material M6 containing isotactic bipyridine thiadiazole acceptors of the present embodiment is:

The synthetic methods of steps (1), (2) and (3) are the same as in Example 4.

(4) Synthesis of target product M6: under nitrogen protection, add 100 mg of intermediate b' (0.13 mmol) and 55.7 mg of 1,1,1,2,2,2-hexamethyldistin to a two-necked flask (0.17 mmol), bis(triphenylphosphine) palladium dichloride (0.01 mmol) and 8 mL of toluene solvent, after stirring at 110 ° C for 1 hour, 106 mg of intermediate a' (0.13 mmol) was added at one time, After continuing to stir at 110° C. for 24 hours, the organic phase was extracted with dichloromethane and saturated brine, dried over anhydrous magnesium sulfate, and the solvent was spin-dried to obtain a crude product. Purified by silica gel column (eluent: petroleum ether:dichloromethane=1:1, V:V) to obtain 89.3 mg of dark purple solid, the target product M6 (yield=47%).

The structural representation data is as follows:

¹ H NMR (400MHz, CDCl ₃ ), δ(ppm): 9.61(s, 1H), 9.24(s, 1H), 8.83(d, 1H), 8.24(d, 1H), 8.10(t, 4H), 7.75(s, 1H), 7.68–7.63(m, 2H), 7.60–7.58(m, 2H), 7.52(d, 1H), 7.47(t, 2H), 7.39(d, 2H), 7.24(d, 2H), 4.20(d, 4H), 2.18(s, 2H), 1.41–1.21(m, 80H), 0.85(td, 12H). ¹³ C NMR (100MHz, CDCl ₃ ), δ(ppm): 157.40, 155.08,153.77,151.63,149.75,148.61,148.54,148.27,148.17,147.86,147.32,141.57,141.17,140.39,140.12,135.01,134.75,131.07,131.00,129.93,126.08,125.86,125.79,124.84,123.99,123.17, 122.84,122.48,121.62,121.47,120.70,120.60,120.38,120.31,119.12,119.06,117.33,117.26,117.19,109.13,106.38,106.08,47.67,37.96,37.88,31.93,30.01,29.67,29.64,29.37,29.36, 26.64, 22.69, 14.13. HRMS: m/z[M] ⁺ calcd for (C ₉₀ H ₁₁₈ N ₈ S ₄ ): 1438.8356; found: 1438.8361.

It can be seen from the above that the structure of this compound is correct, and it is the target product M6 shown.

Test 1:

The structural regularity of the target products M1, M2, M3, M4, M5, and M6 in Examples 1 to 6 was determined:

Fig. 1 and Fig. 2 are the ¹ H- ¹ H NOE spectra of M1 when the mixing time is 0.3s and 0.8s, respectively. It can be seen from the figures that the protons on PT (δ=9.37ppm) and the protons on the adjacent thiophene (δ=9.37ppm) = 8.60 ppm) without any correlation peak, thus confirming that the structural regularity of the target product M1 is correct;

Fig. 3 and Fig. 4 are the ¹ H- ¹ H NOE spectra of M2 when the mixing time is 0.3s and 0.8s, respectively. It can be seen from the figures that the protons on PT (δ=9.16ppm) and the protons on the adjacent thiophene (δ=9.16ppm) = 8.12ppm), no correlation peak was found, thus confirming that the structural regularity of the target product M2 is correct;

Fig. 5 and Fig. 6 are the ¹ H- ¹ H NOE spectra of M3 when the mixing time is 0.3s and 0.8s, respectively. It can be seen from the figures that the protons on PT (δ=9.49/9.13ppm) and the protons on the adjacent thiophene (δ=8.68/8.05ppm) did not find any correlation peak, thus confirming that the structural regularity of the target product M3 is correct;

Figures 7 and 8 are the ¹ H- ¹ H NOE spectra of M4 when the mixing time is 0.3s and 0.8s, respectively. It can be seen from the figures that the protons on PT (δ=9.66ppm) and the protons on the adjacent thiophene (δ=9.66ppm) = 8.56ppm) without any correlation peak, thus confirming that the structural regularity of the target product M4 is correct;

Figures 9 and 10 show the ¹ H- ¹ H NOE spectra of M5 with mixing time of 0.3s and 0.8s, respectively. It can be seen from the figures that the protons on PT (δ=9.30ppm) and the protons on the adjacent thiophene (δ=9.30ppm) = 8.34ppm), no correlation peak was found, thus confirming that the structural regularity of the target product M5 is correct;

Figures 11 and 12 are the ¹ H- ¹ H NOE spectra of M6 with mixing time of 0.3s and 0.8s, respectively. It can be seen from the figures that the protons on PT (δ=9.61/9.24ppm) and the protons on the adjacent thiophene (δ=8.83/8.25ppm), no correlation peak was found, thus confirming that the structural regularity of the target product M6 is correct.

Test 2:

Determination of the absorption spectrum properties of the target products M1, M2 and M3: Figure 13 shows the UV-Vis-NIR absorption spectra of the target products M1, M2 and M3 in chloroform solution; Figure 14 shows the target products M1, M2 and Ultraviolet–visible–near-infrared absorption spectra of M3 films on quartz plates. In the chloroform solution, the target products M1, M2 and M3 exhibited spectral absorption ranges of 250-642 nm, 250-649 nm and 250-656 nm, respectively, and their film absorption maximum absorption sideband values were 642 nm, 649 nm and 656 nm, respectively. The corresponding optical band gaps of the target products M1, M2 and M3 are 1.93 eV, 1.91 eV and 1.89 eV respectively (the optical band gap is calculated according to the formula E _g = 1240/λ, where E _g is the optical band gap and λ is the absorption maximum absorption of the film. sideband value).

Test 3:

Determination of the absorption spectrum properties of the target products M4, M5 and M6: Figure 15 shows the UV-Vis-NIR absorption spectra of the target products M4-M6 in chloroform solution; Figure 16 shows the target products M4-M6 on a quartz plate UV-Vis-NIR absorption spectra of thin films. In the chloroform solution, the target products M4, M5 and M6 exhibited spectral absorption ranges of 300-699 nm, 300-686 nm and 300-690 nm, respectively, and their thin-film absorption maximum absorption sideband values were 699 nm, 686 nm and 690 nm, respectively. The corresponding optical band gaps of the target products M4, M5 and M6 are 1.77 eV, 1.81 eV and 1.80 eV respectively (the optical band gap is calculated according to the formula E _g = 1240/λ, where E _g is the optical band gap and λ is the absorption maximum absorption of the film. sideband value).

Test 4:

The molar extinction coefficients were measured for the target products M1, M2, M3, M4, M5 and M6 in Examples 1 to 6: Figure 17 shows the target products M1, M2 and M3 in trichloric solution (C=1×10 ^{− 5} M) in the molar extinction coefficient spectrum; Figure 18 is the molar extinction coefficient spectrum of the target products M4, M5 and M6 in trichloride solution (C=1×10 ^-5 M). It can be seen from the figure that the molar extinction coefficients of M1, M2 and M3 at the maximum absorption wavelength are 3.13×10 ⁴ M ^-1 cm ^-1 , 2.89×10 ⁴ M ^-1 cm ^-1 and 3.04×10 ⁴ M ^-1 cm -1 ^, respectively ^-1 , M4, M5 and M6 have molar extinction coefficients of 6.58×10 ⁴ M ^-1 cm ^-1 , 4.90×10 ⁴ M ^{- 1} cm ^-1 and 5.93×10 ⁴ M ^-1 cm -1 at the maximum absorption wavelength ^, respectively ¹ ; It was found that the molar extinction coefficient values of the target products M4, M5 and M6 were twice that of M1, M2 and M3.

Test 5:

Measure the fluorescence spectra of the target products M1, M2, M3, M4, M5 and M6 in Examples 1 to 6: Figure 19 is the fluorescence spectra of the target products M1, M2 and M3 in trichloride solution; Figure 20 respectively Fluorescence spectra of target products M4, M5 and M6 in trichloride solution. It can be seen from the figure that the maximum emission wavelengths of M1, M2 and M3 are 615nm, 621nm and 631nm respectively; the maximum emission wavelengths of M4, M5 and M6 are 670nm, 707nm and 690nm respectively.

Test 6:

The electrochemical properties of the target products M1, M2, M3, M4, M5 and M6 in Examples 1 to 6 were measured: Figure 21 is the cyclic voltammetry curves of the target products M1, M2 and M3 in chloroform solution; Figure 2 22 is the cyclic voltammetry curves of target products M4, M5 and M6 in chloroform solution. The test conditions are as follows: the three-electrode working system is used to measure the redox potential, the glassy carbon electrode is selected as the working electrode, the Ag/AgCl is used as the reference electrode, the platinum wire electrode is used as the counter electrode, and the concentration of tetrabutylhexafluorophosphoric acid is 0.1mol/L. Ammonium in chloroform was used as the supporting electrolyte, ferrocene was used as the internal standard (0.38 V vs. Ag/AgCl), and the scan rate was 100 mV/s. It can be seen from Figure 21 that the HOMO and LUMO energy levels of M1, M2 and M3 are –5.19eV/–3.57eV, –5.21eV/–3.69eV and –5.20eV/–3.61eV respectively; it can be seen from Figure 22 that M4, M5 The HOMO and LUMO levels of M6 and M6 are –5.25eV/–3.62eV, –5.23eV/–3.75eV and –5.24eV/–3.67eV, respectively.

Example 7:

An application of the organic small molecule conjugated material M4 containing an isotactic bipyridine thiadiazole acceptor in the preparation of a top-gate bottom-contact FET device in Example 4, the schematic structural diagram of the top-gate bottom-contact FET device is shown in Figure 23 As shown, its application method is:

(1) Using glass as the substrate, the gold source/drain electrodes are composed of 30nm gold and 5nm titanium, and the channel width (W) and channel length (L) of the FET device are 1400μm and 5μm, respectively;

(2) In a nitrogen box, the organic semiconductor material M4 was prepared into a dichlorobenzene solution with a concentration of 10 mg/mL, and then a semiconductor active layer film with a thickness of 40 nm was spin-coated on the surface of the glass substrate, and finally the film sample was placed Annealed on a hot stage at 120°C for 10min;

(3) Subsequently, a PMMA dielectric layer film with a thickness of about 900 nm was formed on the surface of the semiconductor layer by spin coating a 60 mg/mL solution of polymethyl methacrylate (PMMA) in butyl acetate. In order to remove the butyl acetate solvent in the dielectric layer, the whole device was baked in a vacuum drying oven at 80°C for 30 minutes;

(4) Finally, a layer of aluminum with a thickness of about 100 nm is vapor-deposited on the PMMA dielectric layer as the gate electrode;

The semiconductor characteristics of the device were measured with a Keithley 4200SCS semiconductor tester under 20-40% air humidity. The hole and electron mobilities in the device saturation region are calculated from the following equation: I _DS =(W/2L)C _i μ(V _G −V _T ) ² (saturation region, V _DS =V _G −V _T ). where I _DS is the drain current, μ is the carrier mobility, V _G is the gate voltage, V _T is the threshold voltage, and C _i is the insulator capacitance.

24 is a graph showing the output characteristics of the FET device prepared in Example 4 of the present invention, using the organic small molecule conjugated material M4 containing isotactic bipyridine thiadiazole acceptors as the organic active semiconductor layer. The curve shows a good linear region and saturation region, indicating that the FET device based on the organic semiconductor material M4 has good field effect control performance.

FIG. 25 is a transfer characteristic curve diagram of a FET device using the organic small molecule conjugated material M4 containing an isotactic bipyridine thiadiazole acceptor as the organic active semiconductor layer prepared in Example 4 of the present invention. The device exhibits unipolar p-type transport device performance with a hole mobility of 0.05 cm ² /V s.

The above research results show that the present invention provides a method for regulating the structure of D-A type organic small molecule conjugated materials containing bipyridine thiadiazole acceptor units, and provides formula (I), formula (II) and formula (III) The organic small molecule conjugated material containing isotactic bipyridine thiadiazole acceptors. Such materials have the advantages of high electron affinity, large coplanar framework, strong heteroatom interaction, structurally regular molecular framework, and good solution processability. The material provided by the invention has the advantages of simple and efficient preparation method, easy availability of raw materials and strong popularization. By changing the substitution positions of different substituted alkyl chains, heteroatom substitutions, electron donor units and pyridine nitrogen atoms, a series of D-A-type organic small molecule conjugated materials containing double acceptor units with excellent comprehensive properties can be prepared.

The above descriptions are only preferred embodiments of the present invention, and do not limit the present invention in any form. Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art, without departing from the spirit and technical solutions of the present invention, can make many possible changes and modifications to the technical solutions of the present invention by using the methods and technical contents disclosed above, or modify them to be equivalent. Variant equivalent embodiments. Therefore, any simple modification, equivalent replacement, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims (10)

1. The organic small molecule conjugated material containing the isotactic bipyridine thiadiazole receptor is characterized by having a structural formula shown as the following formula (I), formula (II) or formula (III):

in the formula (I), the formula (II) or the formula (III), Ar is one of structural formulas shown in a formula (IV) or a formula (V),

in the formula (IV) or the formula (V), R₁Is selected from C₄-C₁₆Linear alkyl radical of (2), R₂Is selected from C₈-C₃₀A branched alkyl group.

2. The isotactic bipyridine thiadiazole receptor-containing small organic molecule conjugate material as claimed in claim 1, wherein R is₁Is n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl or n-hexadecyl; the R is₂Is 2-ethylhexyl, 2-butylhexyl, 2-hexyloctyl, 4-hexyldecyl, 3-hexylundecyl, 2-octyldecyl, 2-octyldodecyl, 3-octyltridecyl, 2-decyldodecyl2-decyltetradecyl, 3-decylpentadecyl, 2-dodecylhexadecyl, 4-octyltetradecyl, 4-decylcetyl, 4-hexyldecyl, 4-octyldodecyl, 4-decyltetradecyl or 4-dodecylhexadecyl.

3. The organic small molecule conjugated material containing the isotactic bipyridine thiadiazole receptor according to claim 1 or 2, wherein the organic small molecule conjugated material containing the isotactic bipyridine thiadiazole receptor is M1, M2, M3, M4, M5 or M6, and respectively corresponds to structural formulas shown as the following formula VI, formula VII, formula VIII, formula IX, formula X and formula XI:

4. a method for preparing the organic small molecule conjugated material containing the isotactic bipyridine thiadiazole receptor according to any one of claims 1 to 3, comprising the following steps:

(1) under the protection of nitrogen, converting the aromatic compound intermediate Ar into lithium salt by using butyl lithium, and then adding tributyltin chloride to obtain the tributyltin alkyl aromatic compound intermediate shown in the formula (XII):

in the formula (XII), Ar is one of structural formulas shown in a formula (IV) or a formula (V);

(2) under the protection of nitrogen, carrying out palladium-catalyzed Stille coupling reaction on tributyltin alkyl aromatic compound intermediate formula (XII) and 7-bromo-4-chloro [1,2,5] thiadiazole [3,4-c ] pyridine to obtain intermediates a and b;

the structural formula of the intermediate a is as follows:

the structural formula of the intermediate b is as follows:

in the formula a or b, Ar is one of structural formulas shown in formula (IV) or formula (V);

(3) preparation of formula (I): under the protection of nitrogen, the intermediate a and the diboron pinacol ester are subjected to Suzuki coupling reaction under the catalysis of palladium to obtain a target product formula (I) with pyridine N atoms facing outwards,

alternatively, formula (II) is prepared: under the protection of nitrogen, the intermediate b and 1,1,1,2,2, 2-hexamethyl-ditin are subjected to Stille coupling reaction under the catalysis of palladium to obtain a target product formula (II) with pyridine N atoms facing inwards,

alternatively, formula (III) is prepared: under the protection of nitrogen, the intermediate b reacts with 1,1,1,2,2, 2-hexamethyl-ditin for 1 hour under the catalysis of palladium, then the intermediate a is added once again, Stille coupling reaction is continued to occur, and a target product formula (III) with pyridine N atoms facing to the same side is obtained,

5. the method for preparing the organic small molecule conjugated material containing the isotactic bipyridine thiadiazole receptor according to claim 4, wherein the step (1) specifically comprises the following steps: under the protection of nitrogen, mixing the aromatic compound intermediate (Ar) with a solvent, adding n-butyllithium at-78 ℃, reacting for 0.5 to 2 hours, adding tributyltin chloride, reacting for 5 to 30 hours at room temperature, extracting dichloromethane and saturated saline solution, separating an organic phase, drying with anhydrous magnesium sulfate, filtering, and removing the solvent in a rotating manner to obtain the tributylstannyl aromatic intermediate shown in formula XII. The feeding molar ratio of the aromatic compound intermediate (Ar), n-butyl lithium to tributyl tin chloride is 1.0: 1.0-1.3: 1.0 to 1.3;

the step (2) is specifically as follows: under the protection of nitrogen, mixing a tributyltin alkyl aromatic compound intermediate shown in a formula (XII), 7-bromo-4-chloro [1,2,5] thiadiazole [3,4-c ] pyridine, a palladium catalyst and a solvent, stirring and reacting for 5-24 hours at 70-150 ℃, extracting dichloromethane and saturated saline, separating an organic phase, drying anhydrous magnesium sulfate, filtering, and removing the solvent in a rotating manner to obtain an intermediate compound a and an intermediate compound b, wherein the feeding molar ratio of the intermediate shown in the formula (XII), the 7-bromo-4-chloro [1,2,5] thiadiazole [3,4-c ] pyridine and the palladium catalyst is 1.0: 1.0-1.5: 0.005 to 0.2;

the preparation of the formula (I) in the step (3) is specifically as follows: under the protection of nitrogen, mixing the intermediate a, pinacol diboron, potassium acetate, a palladium catalyst and a solvent, stirring and reacting at 70-150 ℃ for 5-24 hours, cooling the mixture solution to room temperature, extracting dichloromethane and saturated saline solution, separating an organic phase, drying anhydrous magnesium sulfate, filtering, removing the solvent by spinning, and purifying a crude product by silica gel column chromatography to obtain a target product formula (I) with pyridine N atoms facing outwards, wherein the feeding molar ratio of the intermediate a, pinacol diboron, potassium acetate and the palladium catalyst is 1.0: 1.0-2.0: 1.0-3.0: 0.005 to 0.2;

the preparation of the formula (II) in the step (3) is specifically as follows: under the protection of nitrogen, mixing an intermediate b, 1,1,1,2,2, 2-hexamethyl ditin, a palladium catalyst and a solvent, stirring and reacting at 70-150 ℃ for 10-24 hours, cooling the mixture solution to room temperature, extracting with dichloromethane and saturated saline solution, separating an organic phase, drying with anhydrous magnesium sulfate, filtering, removing the solvent by spinning, and purifying a crude product by silica gel column chromatography to obtain a target product formula (II) with pyridine N atoms facing outwards, wherein the feeding molar ratio of the intermediate b, 1,1,1,2,2, 2-hexamethylditin to the palladium catalyst is 1.0: 0.4-1.0: 0.01 to 0.2;

the preparation of the formula (III) in the step (3) is specifically as follows: under the protection of nitrogen, mixing an intermediate b, a palladium catalyst, 1,1,1,2,2, 2-hexamethyl ditin and a solvent, stirring and reacting for 0.5-2 hours at 70-150 ℃, then adding the intermediate a at one time, continuously stirring and reacting for 3-24 hours at 70-150 ℃, cooling the mixture solution to room temperature, extracting by using dichloromethane and saturated saline solution, separating an organic phase, drying anhydrous magnesium sulfate, filtering, removing the solvent by spinning, purifying the crude product by silica gel column chromatography to obtain a target product formula (III) with pyridine N atoms facing to the same side, wherein the feeding molar ratio of the intermediate b, the intermediate a, 1,1,1,2,2, 2-hexamethylditin to the palladium catalyst is 1.0: 1.0: 0.8-1.6: 0.01 to 0.2.

6. The method for preparing the organic small molecule conjugated material containing the isotactic bipyridine thiadiazole receptor according to claim 4, wherein the formula (IV) is prepared by the following method: under the protection of nitrogen, converting thiophene into thiophene lithium salt by using butyl lithium, and then adding 1-bromoalkane to obtain a 2-alkylthiophene intermediate shown in a formula (IV);

and/or, the formula (V) is prepared by the following method:

(S1) under the protection of nitrogen, reacting 2-bromocarbazole with 1-bromoalkane by adopting a nucleophilic substitution method to obtain a 2-bromo-9-alkyl substituted carbazole intermediate c;

the structural formula of the intermediate c is as follows:

wherein, R is₂Is as defined in claim 1,2 or 3;

(S2) under the protection of nitrogen, performing Stille coupling reaction to react the intermediate c with a thiophene butyl tin reagent to obtain any one of the structures shown in the formula (V).

7. The method for preparing the organic small molecule conjugated material containing the isotactic bipyridine thiadiazole receptor according to claim 6, wherein the preparation process of the formula (IV) specifically comprises the following steps: under the protection of nitrogen, thiophene and a solvent are mixed, n-butyl lithium is added at-78 ℃ for reaction for 1.5-2 hours, 1-bromoalkane is added for reaction overnight, dichloromethane and saturated saline solution are used for extraction, an organic phase is separated, anhydrous magnesium sulfate is used for drying, and after filtration, the solvent is removed in a rotating mode to obtain a 2-alkylthiophene intermediate shown in a formula (IV); the feeding molar ratio of the thiophene, the n-butyl lithium and the 1-bromoalkane is 1.0: 1.0-1.3: 1.0 to 1.3;

and/or in the preparation process of the formula (V), (S1) is specifically: under the protection of nitrogen, mixing 2-bromocarbazole, 1-bromoalkane, sodium hydride and a solvent, stirring and reacting for 5-24 hours at 50-150 ℃, extracting by using dichloromethane and saturated salt water, separating an organic phase, drying anhydrous magnesium sulfate, filtering, and then removing the solvent in a rotating manner to obtain a 2-bromo-9-alkyl substituted carbazole intermediate c; the feeding molar ratio of the 2-bromocarbazole to the 1-bromoalkane to the sodium hydride is 1.0: 1.0-3.0: 1.0 to 3.0;

the step (S2) is specifically: under the protection of nitrogen, mixing a 2-bromo-9-alkyl substituted carbazole intermediate c, a thiophene butyl tin reagent, a palladium catalyst and a solvent, stirring and reacting for 5-24 hours at 70-150 ℃, extracting by using dichloromethane and saturated salt water, separating an organic phase, drying anhydrous magnesium sulfate, filtering, and removing the solvent in a rotating manner to obtain any compound in the structure shown in the formula (V); the feeding molar ratio of the 2-bromo-9-alkyl substituted carbazole intermediate c to the thiophene butyl tin reagent to the palladium catalyst is 1.0: 1.0-3.0: 0.01 to 0.2.

8. The method for preparing the organic small molecule conjugate material containing the isotactic bipyridine thiadiazole acceptor according to any one of claims 4 to 7, wherein the palladium catalyst is at least one selected from the group consisting of tetrakis (triphenylphosphine) palladium, bis (triphenylphosphine) palladium dichloride, palladium acetate and tris (dibenzylideneacetone) dipalladium; the solvent is at least one selected from toluene, xylene, trimethylbenzene, N '-dimethylformamide, N' -dimethylacetamide, N-methylpyrrolidone, chlorobenzene, dichlorobenzene, trichlorobenzene, 1, 4-dioxane, tetrahydrofuran, acetonitrile and 1, 4-dioxane.

9. An application of the organic small molecule conjugated material containing the isotactic bipyridine thiadiazole receptor according to any one of claims 1 to 3 or the organic small molecule conjugated material containing the isotactic bipyridine thiadiazole receptor prepared by the preparation method according to any one of claims 4 to 8 in preparation of an organic thin film field effect transistor device.

10. The application according to claim 9, wherein the application method is as follows: firstly, dissolving an organic small molecule conjugated material containing an isotactic bipyridine thiadiazole receptor in a trichloromethane solution, and spin-coating the obtained solution on the surface of a glass substrate to obtain an organic semiconductor active layer film; secondly, spin-coating a butyl acetate solution of polymethyl methacrylate on the surface of the organic semiconductor active layer film to obtain a polymethyl methacrylate dielectric layer; and finally, evaporating a layer of aluminum on the polymethyl methacrylate dielectric layer to be used as a gate electrode.

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