JP6780365B2 - Heteroacene derivatives, organic semiconductor layers, and organic thin film transistors - Google Patents

Description

The present invention relates to a novel heteroacene derivative that can be applied to electronic materials such as organic semiconductor materials, an organic semiconductor layer using the same, and an organic thin film transistor, and is particularly excellent in heat resistance, so that it can be used in various device manufacturing processes. It relates to a novel heteroacen derivative that can be applied, an organic semiconductor layer using the same, and an organic thin film transistor.

Organic semiconductor devices represented by organic thin film transistors have been attracting attention in recent years because they have features such as energy saving, low cost, and flexibility that are not found in inorganic semiconductor devices. This organic semiconductor device is composed of several kinds of materials such as an organic semiconductor layer, a substrate, an insulating layer, and an electrode. Among them, the organic semiconductor layer responsible for charge carrier transfer plays a central role in the device. Since the performance of an organic semiconductor device depends on the carrier mobility of the organic semiconductor material constituting the organic semiconductor layer, the appearance of an organic semiconductor material that gives high carrier mobility is desired.

As a method for producing an organic semiconductor layer, a vacuum vapor deposition method in which an organic material is vaporized under a high-temperature vacuum and a coating method in which the organic material is dissolved in an appropriate solvent and the solution is applied are generally known. Has been done. Of these, the coating method can be carried out by using printing technology without using high-temperature and high-vacuum conditions, so that it can be expected to significantly reduce the manufacturing cost of device fabrication, which is an economically preferable process. Is.

The organic semiconductor material used in such a coating method preferably has a heat resistance of 150 ° C. or higher from the viewpoint of high carrier mobility and device manufacturing process. In addition, it is preferable to have appropriate solubility from the viewpoint of adaptation to the printing process. Further, it is preferable to have oxidation resistance for stable operation in the atmosphere.

Among organic semiconductor materials, low-molecular-weight semiconductors are known to easily exhibit high carrier mobility because they have higher crystallinity than high-molecular-weight semiconductors. However, at present, little is known about low-molecular-weight organic semiconductor materials that have appropriate solubility and high oxidation resistance in addition to high carrier mobility.

Currently, pentacene is widely known as a low molecular weight material. Pentacene is known to have high carrier mobility, but it is extremely easily air-oxidized in a solution state and has a problem in oxidation resistance.

Dialkyl-substituted benzothienobenzothiophene (see, for example, Patent Document 1), 2,7-dihexyldithienobenzodithiophene (see, for example, Patent Document 2) and the like have been proposed as low molecular weight materials having oxidation resistance. ing.

However, in the case of the dialkyl-substituted benzothienobenzothiophene described in Patent Document 1, there is a problem that the transistor operation is lost when the heat treatment is performed at 130 ° C. Further, 2,7-dihexyldithienobenzodithiophene described in Patent Document 2 has a melting point of 190 ° C., and further improvement in heat resistance is desired by increasing the melting point.

WO2008 / 047896 Japanese Unexamined Patent Publication No. 2012/209329

The present invention has been made in view of the above problems, and an object of the present invention is to provide a novel coating type organic semiconductor material having high carrier mobility, high heat resistance, high oxidation resistance and appropriate solubility. There is.

As a result of diligent studies to solve the above problems, the present inventor has found that a novel heteroacene derivative imparts high carrier mobility and also has high heat resistance, high oxidation resistance and appropriate solubility. The invention has been completed.

That is, the present invention relates to a heteroacen derivative, a method for producing the same, an organic semiconductor layer, and an organic thin film transistor using the same, which is represented by the following general formula (1).

（ここで、Ｒ^１〜Ｒ^４は、それぞれ独立して、水素、ハロゲン、炭素数１〜２０のアルキル基、炭素数１〜２０のアシル基、炭素数４〜２２のアリール基、炭素数２〜２０のアルケニル基、または炭素数２〜２０のアルキニル基を示す。Ｔ^１及びＴ^２は、それぞれ独立して硫黄原子、酸素原子、またはセレン原子を示す。また、環Ａ及びＢはそれぞれ独立して５員環であり、それぞれ下記一般式（Ａ）、（Ｂ）で示される構造を示す。）

(Here, R ^{1 to} R ⁴ are independently hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms, an acyl group having 1 to 20 carbon atoms, an aryl group having 4 to 22 carbon atoms, and 2 carbon atoms. It represents an alkenyl group of ~ 20 or an alkynyl group having 2 to 20 carbon atoms. T ¹ and T ² independently represent a sulfur atom, an oxygen atom, or a selenium atom, and rings A and B are independent of each other. It is a 5-membered ring and shows the structures represented by the following general formulas (A) and (B), respectively.)

（ここで、Ｒ^５〜Ｒ^８は、それぞれ独立して、水素、ハロゲン、炭素数１〜２０のアルキル基、炭素数１〜２０のアシル基、炭素数４〜２２のアリール基、炭素数２〜２０のアルケニル基、または炭素数２〜２０のアルキニル基を示す。Ｔ^３及びＴ^４は、それぞれ独立して硫黄原子、酸素原子、またはセレン原子を示す。）
以下に本発明を詳細に説明する。

(Here, R ^{5 to} R ⁸ are independently hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms, an acyl group having 1 to 20 carbon atoms, an aryl group having 4 to 22 carbon atoms, and 2 carbon atoms. It represents an alkenyl group of ~ 20 or an alkynyl group having 2 to 20 carbon atoms. T ³ and T ⁴ independently represent a sulfur atom, an oxygen atom, or a selenium atom.)
The present invention will be described in detail below.

The heteroacene derivative used in the present invention is a derivative represented by the above general formula (1), and R ^{1 to} R ⁴ are independently hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms, and 1 to 1 carbon atoms. It represents an acyl group of 20, an aryl group having 4 to 22 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or an alkynyl group having 2 to 20 carbon atoms. T ¹ and T ² independently represent a sulfur atom, an oxygen atom, or a selenium atom, respectively. Further, the rings A and B are independently 5-membered rings, respectively, and show the structures represented by the above general formulas (A) and (B), respectively, and R ^{5 to} R ⁸ are independently hydrogen and halogen, respectively. , An alkyl group having 1 to 20 carbon atoms, an acyl group having 1 to 20 carbon atoms, an aryl group having 4 to 22 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or an alkynyl group having 2 to 20 carbon atoms. T ³ and T ⁴ independently represent a sulfur atom, an oxygen atom, or a selenium atom, respectively.

The halogen in R ^{1 to} R ⁴ and R ^{5 to} R ⁸ is not particularly limited, and examples thereof include fluorine, chlorine, bromine, and iodine, and chlorine and fluorine are preferable because of their high stability.

The alkyl group having 1 to 20 carbon atoms in R ^{1 to} R ⁴ and R ^{5 to} R ⁸ is not particularly limited, and for example, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an isobutyl group, n- Pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-dodecyl group, n-tetradecyl group, 2-ethylhexyl group, 3-ethylheptyl group, 3 Examples thereof include a linear or branched alkyl group such as an ethyldecyl group and a 2-hexyldecyl group. Among them, an alkyl group having 3 to 14 carbon atoms is preferable, an alkyl group having 3 to 10 carbon atoms is more preferable, and an n-propyl group is preferable because the heteroacene derivative exhibits high carrier mobility and high solubility. More preferably, it is an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group and an n-decyl group.

The acyl group having 1 to 20 carbon atoms in R ^{1 to} R ⁴ and R ^{5 to} R ⁸ is not particularly limited, and for example, a formyl group, an acetyl group, a propionyl group, a butyryl group, an isobutyryl group, a valeryl group, a hexanoyl group, and the like. Examples thereof include a linear or branched acyl group such as a heptanoid group, an octanoyl group, a nonanoyl group, a decanoyyl group, a dodecanoyl group, a 2-ethylhexanoyl group, a 3-ethylheptanoil group and a 3-ethyldecanoyl group. Among them, an acyl group having 3 to 14 carbon atoms is preferable, an acyl group having 3 to 10 carbon atoms is more preferable, and a propionyl group and a butyryl group are preferable because the heteroacene derivative exhibits particularly high carrier mobility and high solubility. , Valeryl group, hexanoyl group, heptanoyle group, octanoyl group are particularly preferable.

The aryl group having 4 to 22 carbon atoms in R ^{1 to} R ⁴ and R ^{5 to} R ⁸ is not particularly limited, and for example, a phenyl group; a p-tolyl group, a p- (n-hexyl) phenyl group, p-( Alkyl-substituted phenyl groups such as n-octyl) phenyl group and p- (2-ethylhexyl) phenyl group; 2-furyl group; 2-thienyl group; 5-fluoro-2-furyl group, 5-methyl-2-furyl group , 5-Ethyl-2-furyl group, 5- (n-propyl) -2-furyl group, 5- (n-butyl) -2-furyl group, 5- (n-pentyl) -2-furyl group, 5 -(N-Hexyl) -2-furyl group, 5- (n-octyl) -2-furyl group, 5- (2-ethylhexyl) -2-furyl group, 5-fluoro-2-thienyl group, 5-methyl -2-thienyl group, 5-ethyl-2-thienyl group, 5- (n-propyl) -2-thienyl group, 5- (n-butyl) -2-thienyl group, 5- (n-pentyl) -2 Alkyl-substituted chalcogenophene groups such as -thienyl group, 5- (n-hexyl) -2-thienyl group, 5- (n-octyl) -2-thienyl group, 5- (2-ethylhexyl) -2-thienyl group and the like. be able to.

The alkenyl group having 2 to 20 carbon atoms in R ^{1 to} R ⁴ and R ^{5 to} R ⁸ is not particularly limited, and for example, an ethenyl group, an n-propenyl group, an n-butenyl group, an n-pentenyl group, and an n-hexenyl group. Examples thereof include a group, an n-heptenyl group, an n-octenyl group, an n-nonel group, an n-decenyl group, an n-dodecenyl group, an n-tetradecenyl group and the like.

The alkynyl group having 2 to 20 carbon atoms in R ^{1 to} R ⁴ and R ^{5 to} R ⁸ is not particularly limited, and is, for example, an ethynyl group, an n-propynyl group, an n-butynyl group, an n-pentynyl group, or an n-hexynyl group. Examples thereof include a group, an n-heptinyl group, an n-octynyl group, an n-noninyl group, an n-decynyl group, an n-dodecynyl group, an n-tetradecynyl group and the like.

In the present invention, as a combination of R ^{1 to} R ⁴ and R ^{5 to} R ⁸ , due to high carrier mobility, R ⁵ and R ⁷ are independently hydrogen, halogen, and alkyl groups having 1 to 20 carbon atoms, respectively. It is selected from the group consisting of an acyl group having 1 to 20 carbon atoms, an aryl group having 4 to 22 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, and an alkynyl group having 2 to 20 carbon atoms, and R ^{1 to} R ⁴ , R. ^It is preferable that ⁶ and R ⁸ are hydrogen, and for higher carrier mobility, R ⁵ and R ⁷ are independently hydrogen, an alkyl group having 1 to 20 carbon atoms, and an acyl group having 1 to 20 carbon atoms. It is more preferable that R ^{1 to} R ⁴ , R ⁶ and R ⁸ are hydrogens, and R ⁵ and R ⁷ are independently alkyl groups having 1 to 20 carbon atoms. Moreover, it is particularly preferable that R ^{1 to} R ⁴ , R ⁶ and R ⁸ are hydrogen.

T ¹ through T ⁴ of the heteroacene derivative represented by the general formula (1) present invention, showing each independently a sulfur atom, an oxygen atom or a selenium atom. In the present invention, the HOMO level is lowered and the oxidation resistance is improved by introducing a sulfur atom, an oxygen atom, or a selenium atom having a higher electronegativity than a carbon atom into the fused ring skeleton. Is what it is. In the present invention, from the viewpoint of high carrier mobility, it is preferable that T ¹ and T ² are sulfur, and it is more preferable that T ^{1 to} T ⁴ are sulfur atoms.

From the viewpoint of high mobility, the heteroacene derivative of the present invention is preferably a heteroacen derivative having a line-symmetrical main skeleton represented by the following general formula (1-1) or (1-2).

本発明で用いられるヘテロアセン誘導体の具体的例示としては、以下のものを挙げることができる。

Specific examples of the heteroacene derivative used in the present invention include the following.

なお、一般式（１）で示される具体的なヘテロアセン誘導体としては、高耐熱性、高移動度、高溶解性及び高耐酸化性のため、Ｒ^５及びＲ^７が炭素数４〜９のアルキル鎖、Ｒ^１〜Ｒ^４、Ｒ^６及びＲ^８が水素、並びにＴ^１〜Ｔ^４が硫黄原子であるヘテロアセン誘導体（化合物２〜化合物７および化合物９〜化合物１４）が好ましい。

As a specific heteroacene derivative represented by the general formula (1), R ⁵ and R ⁷ are alkyl having 4 to 9 carbon atoms because of high heat resistance, high mobility, high solubility and high oxidation resistance. Heteroacene derivatives (Compounds 2 to Compound 7 and Compounds 9 to 14) in which the chains, R ^{1 to} R ⁴ , R ⁶ and R ⁸ are hydrogen, and T ^{1 to} T ⁴ are sulfur atoms are preferred.

As the method for producing the heteroacene derivative used in the present invention, any production method can be used as long as the heteroacene derivative can be produced. For example, in the case of producing a heteroacene derivative in which R ⁵ and R ⁷ are hydrogen or an alkyl group having 1 to 20 carbon atoms and R ^{1 to} R ⁴ , R ⁶ and R ⁸ are hydrogen in the above general formula (1-1). The heteroacene derivative (compound (1a) in the reaction scheme below) can be produced by the production method through the steps (A) to (F) below. Further, in the case of producing a heteroacene derivative in which R ⁵ and R ⁷ are hydrogen or an alkyl group having 1 to 20 carbon atoms and R ^{1 to} R ⁴ , R ⁶ and R ⁸ are hydrogen in the above general formula (1-2), the following After going through the steps (A) to (B), the heteroacene derivative (compound (2a) in the reaction scheme below) can be produced by the production method through the following steps (C-2) to (F-2).
(A) Step: A step of producing 1,8-dihalonaphthalene-2,7-diol by a halogenation reaction of 2,7-dihydroxynaphthalene in the presence of a halogenating agent.
Step (B): Trifluoromethanesulfonylation of the hydroxy group of 1,8-dihalonaphthalene-2,7-diol obtained by step (A) under basic conditions in the presence of trifluoromethanesulfonic anhydride. A step of producing 1,8-dihalo-2,7-bis (trifluoromethanesulfonyloxy) naphthalene.
Step (C): In the presence of a palladium catalyst, with a 3-halocalcogenophenyl-2-zinc derivative and 1,8-dihalo-2,7-bis (trifluoromethanesulfonyloxy) naphthalene obtained in step (B). A step of producing 2,7-di (3-halocalcogenophenyl-2-) -1,8-dihalonaphthalene by cross-coupling.
Step (D); Intramolecular ring of 2,7-di (3-halocalcogenophenyl-2-) -1,8-dihalonaphthalene obtained by step (C) in the presence of a chalcogenized alkali metal salt. The process of producing unsubstituted heteroacenes by conversion.
Step (E); A step of producing a diacyl heteroacene by a Friedel-Crafts acylation reaction between the unsubstituted heteroacene obtained in the step (D) and an acyl chloride compound.
Step (F); A step of subjecting the diacyl heteroacene obtained in the step (E) to a reduction reaction to produce a heteroacene derivative.
Step (C-2); 2-halocalcogenophenyl-3-zinc derivative in the presence of palladium catalyst and 1,8-dihalo-2,7-bis (trifluoromethanesulfonyloxy) obtained by step (B). A step of producing 2,7-di (2-halocalcogenophenyl-3-) -1,8-dichloronaphthalene by cross-coupling with naphthalene.
Step (D-2); 2,7-di (2-halocalcogenophenyl-3-) -1,8-dihalonaphthalene obtained by step (C-2) in the presence of a chalcogenized alkali metal salt. A step of producing an unsubstituted heteroacene by intramolecular cyclization of.
Step (E-2); A step of producing a diacyl heteroacene by a Friedel-Crafts acylation reaction of the unsubstituted heteroacene obtained in the step (D-2) with an acyl compound chloride.
Step (F-2); A step of subjecting the diacyl heteroacene obtained in the step (E-2) to a reduction reaction to produce a heteroacene derivative.

Then, a more specific production method preferable because the number of reaction steps is small is shown in the following reaction scheme.

（ここで、Ｒ^５及びＲ^７は、それぞれ独立して炭素数１〜２０のアルキル基を示し、Ｒ^９は水素、または炭素数１〜１９のアルキル基を示す。Ｔ^１及びＴ^３は硫黄原子、酸素原子またはセレン原子を示す。置換基Ｘ^１〜Ｘ^２は、それぞれ独立して、ハロゲンを示す。）
ここで、（Ａ）工程はハロゲン化剤存在下、２，７−ジヒドロキシナフタレンのハロゲン化反応により１，８−ジハロナフタレン−２，７−ジオールを製造する工程である。

(Here, R ⁵ and R ⁷ each independently represent an alkyl group having 1 to 20 carbon atoms, R ⁹ represents hydrogen, or an alkyl group having 1 to 19 carbon atoms. T ¹ and T ³ are sulfur. Indicates an atom, an oxygen atom or a selenium atom. Substituents X ^{1 to} X ² independently indicate a halogen.)
Here, the step (A) is a step of producing 1,8-dihalonaphthalene-2,7-diol by a halogenation reaction of 2,7-dihydroxynaphthalene in the presence of a halogenating agent.

Examples of the halogen of 1,8-dihalonaphthalene-2,7-diol include chlorine, bromine, fluorine and iodine.

Examples of the halogenating agent include N-chlorosuccinimide (NCS), N-bromosuccinimide (NBS), N-iodosuccinimide (NIS), chlorine, bromine, iodine, 1-chloromethyl-4-fluoro-1,4. -Diazonia bicyclo [2.2.2] Octanebis (tetrafluoroborate) (product name: Selectfluor) and the like can be mentioned.

Here, the step (B) is the hydroxy of 1,8-dihalonaphthalene-2,7-diol obtained by the step (A) under basic conditions in the presence of trifluoromethanesulfonic anhydride (Tf ₂ O). This is a step of producing 1,8-dihalo-2,7-bis (trifluoromethanesulfonyloxy) naphthalene by trifluoromethanesulfonylation of the group.

Examples of the base used to make the reaction basic conditions include pyridine and triethylamine, and the reaction temperature can be in the range of −80 ° C. to 60 ° C.

Here, in step (C), in the presence of a palladium catalyst, a 3-halocalcogenophenyl-2-zinc derivative and 1,8-dihalo-2,7-bis (trifluoromethanesulfonyloxy) obtained in step (B) were obtained. ) This is a step of producing 2,7-di (3-halocalcogenophenyl-2-) -1,8-dihalonaphthalene by cross-coupling with naphthalene.

The 3-halocalcogenophenyl-2-zinc derivative uses, for example, an organic metal reagent such as ethylmagnesium chloride, isopropylmagnesium bromide, isopropylmagnesium chloride, or phenylmagnesium chloride, and is in the second position of 2,3-dihalocalcogenofen. It can be prepared by exchanging the halogen in magnesium with magnesium halide (preparation of Grignard reagent) and then exchanging metal with zinc chloride. Here, examples of the 2,3-dihalocalcogenophene include 2,3-dibromothiophene, 2,3-dibromoselenovene, 2,3-dibromofuran, 2,3-dichlorothiophene, and 2,3-. Dichloroselenophene, 2,3-dichlorofuran, 2,3-diiodothiophene, 2,3-diiodoselenophene, 2,3-diiodofuran, 2-bromo-3-chlorothiophene, 2-bromo-3-chloro Serenophene, 2-bromo-3-chlorofuran, 2-iodo-3-chlorothiophene, 2-iodo-3-chlorocerenophen, 2-iodo-3-chlorofuran, 2-iodo-3-bromothiophene, 2 -Iodo-3-bromoselenophene, 2-iodo-3-bromofuran and the like can be mentioned. It is also possible to prepare a Grignard reagent of 2,3-dihalocalcogenofen by using magnesium metal instead of the organometallic reagent. The conditions for preparing the Grignard reagent for 2,3-dihalocalcogenofen include, for example, in a solvent such as tetrahydrofuran (hereinafter referred to as THF) or diethyl ether within a temperature range of -80 ° C to 50 ° C. can do. A 3-halocalcogenophenyl-2-zinc derivative can be prepared by reacting a solution of the Grignard reagent with zinc chloride. Zinc chloride may be used as it is or may be a solution of THF or diethyl ether. The temperature of the reaction between the Grignard reagent and zinc chloride can be carried out within the range of −80 ° C. to 30 ° C.

Examples of the halogen of the 3-halocalcogenophenyl-2-zinc derivative include chlorine, bromine, fluorine and iodine. Specific examples of the 3-halocalcogenophenyl-2-zinc derivative include 3-chlorothienyl-2-zinc derivative, 3-bromothienyl-2-zinc derivative, and 3-iodothienyl-2-zinc derivative. 3-Fluorothienyl-2-zinc derivative, 3-chloroselenophenyl-2-zinc derivative, 3-bromoselenophenyl-2-zinc derivative, 3-iodoselenophenyl-2-zinc derivative, 3-fluoroselenophenyl-2 -Zinc derivatives and the like can be mentioned, and among them, 3-chlorothienyl-2-zinc derivatives and 3-bromothienyl-2-zinc derivatives are preferable because they are particularly excellent in reaction efficiency.

Examples of the palladium catalyst include tetrakis (triphenylphosphine) palladium and bis (triphenylphosphine) dichloropalladium, and the reaction temperature in cross-coupling is in the range of 20 ° C to 80 ° C. be able to.

In the step (D), the intramolecular amount of 2,7-di (3-halocalcogenophenyl-2-) -1,8-dihalonaphthalene obtained in the step (C) in the presence of a chalcogenized alkali metal salt was performed. This is a step of producing an unsubstituted heteroacene by cyclization.

Examples of the chalcogenized alkali metal salt include sodium sulfide, potassium sulfide, lithium sulfide, rubidium sulfide, cesium sulfide, sodium selenide, potassium selenium, lithium selenium, rubidium selenium, cesium selenium and its hydrate. Etc., and the intramolecular cyclization reaction is carried out in a solvent such as N-methylpyrrolidone (hereinafter referred to as NMP) and dimethylformamide (hereinafter referred to as DMF) at 80 ° C. to 200 ° C. Can be done in the temperature range of.

As the chalcogenized alkali metal salt used in this step, a commercially available product or one prepared by a known method can be used. For example, as sodium selenide, the one obtained by reducing selenium with sodium borohydride in ethanol can be used as it is.

The step (E) is a step of producing a diacyl heteroacene by a Friedel-Crafts acylation reaction of the unsubstituted heteroacene obtained in the step (D) with an acyl compound chloride in the presence of aluminum chloride as a catalyst.

Examples of the acyl chloride compound include formyl chloride, acetyl chloride, propionyl chloride, butyryl chloride, isobutyryl chloride, valeroyl chloride, hexanoyl chloride, heptanyl chloride, octanoyl chloride, 2-ethylhexanoyl chloride, noninoyl chloride, decanoyl chloride, and chloride. Dodecanoyl, tetradecanoyl chloride and the like can be mentioned. The Friedel-Crafts acylation reaction can be carried out in a solvent such as dichloromethane, 1,2-dichloroethane, toluene and the like in a temperature range of 0 ° C. to 40 ° C.

Further, the step (F) is a step of subjecting the diacyl heteroacene obtained in the step (E) to a reduction reaction to produce a heteroacene derivative.

The reduction reaction of diacyl heteroacene uses, for example, sodium borohydride / aluminum chloride or lithium aluminum hydride / aluminum chloride as a reducing agent in a solvent of THF, diethyl ether, diisopropyl ether, or methyl tertiary butyl ether. It can be carried out in the temperature range of 10 ° C. to 80 ° C. Further, for example, hydrazine can be used as a reducing agent, and it can be carried out in a temperature range of 80 ° C. to 250 ° C. in diethylene glycol, ethylene glycol or triethylene glycol in the presence of potassium hydroxide or sodium hydroxide.

Further, in the step (C-2), in the presence of a palladium catalyst, the 2-halocalcogenophenyl-3-zinc derivative and the 1,8-dihalo-2,7-bis (trifluoromethanesulfonyl) obtained in the step (B) were obtained. This is a step of producing 2,7-di (2-halocalcogenophenyl-3-) -1,8-dihalonaphthalene by cross-coupling with oxy) naphthalene.

The cross-coupling is the same method as in step (C) except that a 2-halocalcogenophenyl-3-zinc derivative is used instead of the 3-halocalcogenophenyl-2-zinc derivative used in step (C). 2,7-Di (2-halocalcogenophenyl-3-) -1,8-dihalonaphthalene can be produced.

The 2-halocalcogenophenyl-3-zinc derivative uses an organic metal reagent such as isopropylmagnesium chloride, isopropylmagnesium bromide, ethylmagnesium chloride, or phenylmagnesium chloride, and is located at the 3-position of 2,3-dihalocalcogenofen. It can be prepared by exchanging the halogen in magnesium with magnesium halide (preparation of Grignard reagent) and then exchanging metal with zinc chloride. Here, examples of 2,3-dihalocalcogenophene include 3-bromo-2-chlorothiophene, 3-bromo-2-chloroselenophene, 3-bromo-2-chlorofuran, and 2-chloro-3. -Iodothiophene, 2-chloro-3-iodoselenophene, 2-chloro-3-iodofuran, 2-bromo-3-iodothiophene, 2-bromo-3-iodothiophene, 2-bromo-3-iodothiophene furan, etc. Can be mentioned.

Examples of the halogen of the 2-halocalcogenophenyl-3-zinc derivative include chlorine, bromine, fluorine and iodine. The 2-halocalcogenophenyl-3-zinc derivative is specifically, for example, 2-chlorothienyl-3-zinc derivative, 2-bromothienyl-3-zinc derivative, 2-iodothienyl-3-zinc derivative, 2-Fluorothienyl-3-zinc derivative, 2-chloroselenophenyl-3-zinc derivative, 2-bromoselenophenyl-3-zinc derivative, 2-iodoselenophenyl-3-zinc derivative, 2-fluoroselenophenyl-3 -Zinc derivatives and the like can be mentioned, and among them, 2-chlorothienyl-3-zinc derivative and 2-bromothienyl-3-zinc derivative are preferable because of their excellent reaction efficiency.

As the palladium catalyst in the step (C-2), the same palladium catalyst as in the step (C) can be used.

In step (D-2), 2,7-di (2-halocalcogenophenyl-3-) -1,8-dihalo obtained by step (C-2) in the presence of a chalcogenized alkali metal salt This is a step of producing an unsubstituted heteroacene by intramolecular cyclization of naphthalene.

The cyclization reaction was obtained in step (C-2) instead of 2,7-di (3-halocalcogenophenyl-2-) -1,8-dihalonaphthalene used in step (D). Unsubstituted heteroacene can be produced by the same method as in step (D) except that 2,7-di (2-halocalcogenophenyl-3-) -1,8-dihalonaphthalene is used.

The step (E-2) is a step of producing a diacyl heteroacene by a Friedel-Crafts acylation reaction of an unsubstituted heteroacene obtained in the step (D-2) with an acyl compound chloride in the presence of aluminum chloride as a catalyst. Is.

The Friedel-Crafts acylation reaction may be carried out in the same manner as in step (E) except that the unsubstituted heteroacene obtained in step (D-2) is used instead of the unsubstituted heteroacene used in step (E). Diacyl heteroacene can be produced.

Further, the step (F-2) is a step of subjecting the diacyl heteroacene obtained in the step (E-2) to a reduction reaction to produce a heteroacene derivative.

The reduction reaction may be carried out in the same manner as in step (F) except that the diacyl heteroacene obtained in step (E-2) is used instead of the diacyl heteroacene used in step (F) to produce a heteroacene derivative. Can be done.

Further, the heteroacene derivative produced in the step (F) or the step (F-2) can be purified by subjecting it to column chromatography or the like, and examples of the separating agent at that time include silica gel, activated alumina, and a solvent. Examples thereof include hexane, heptane, toluene, dichloromethane, chloroform and the like.

The produced heteroacene derivative can be decolorized and purified in a solution by subjecting it to activated charcoal, zeolite, activated clay or the like, and examples of the solvent at that time include hexane, heptane, toluene, dichloromethane, chloroform and the like. ..

Further, the produced heteroacene derivative may be further purified by recrystallization, and the purity can be improved by increasing the number of recrystallizations. The number of recrystallizations is preferably 2 to 5 from the viewpoint of high purity and high yield. Examples of the solvent used for recrystallization include hexane, heptane, octane, toluene, xylene, chloroform, chlorobenzene, dichlorobenzene and the like, and may be a mixture of any ratio thereof.

As a recrystallization method, a solution of a heteroacene derivative is prepared by heating (the concentration of the solution at that time is preferably in the range of 0.01 to 10.0% by weight in order to efficiently remove impurities, and is preferably 0.05 to 0.05. The range of 5.0% by weight is more preferable.) By cooling the solution, crystals of the heteroacene derivative are precipitated and isolated, but the final cooling temperature at the time of isolation is to improve the purity and recovery rate. Therefore, it is preferably in the range of −20 ° C. to 40 ° C. When measuring the purity, it can be analyzed by liquid chromatography.

The heteroacene derivative of the present invention can be made into a solution for forming an organic semiconductor layer by dissolving it in an appropriate solvent. As the solvent, any solvent may be used as long as it can dissolve the heteroacene derivative represented by the general formula (1), and the drying rate of the solvent is preferable when forming the organic semiconductor layer. An organic solvent having a boiling point at normal pressure of 100 ° C. or higher is preferable because it can be used.

Examples of the solvent that can be used in the present invention include aromatic hydrocarbons such as toluene, mesityrene, o-xylene, isopropylbenzene, pentylbenzene, cyclohexylbenzene, 1,2,4-trimethylbenzene, tetraline, and indan. Anisole, 2-methylanisole, 3-methylanisole, 2,3-dimethylanisole, 3,4-dimethylanisole, 2,6-dimethylanisole, ethylphenyl ether, butylphenyl ether, 1,2-methylenedioxybenzene , 1,2-ethylenedioxybenzene and other aromatic ethers; chlorobenzene, 1,2-dichlorobenzene, 1,3-dichlorobenzene, 1,4-dichlorobenzene and other aromatic halogen compounds; cyclohexane, octane, decane , Dodecane, saturated hydrocarbons such as decalin; dipropylene glycol dimethyl ether, dipropylene glycol diacetate, dipropylene glycol methyl-n-propyl ether, dipropylene glycol methyl ether acetate, 1,4-butanediol diacetate, 1, 3-butylene glycol diacetate, 1,3-butylene glycol diacetate, 1,6-hexanediol diacetate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol Glycols such as monobutyl ether acetate; esters such as phenylacetate, cyclohexanol acetate, and 3-methoxybutyl acetate can be mentioned, and among them, toluene and o-xylene are preferable because they have an appropriate drying rate. , Mesitylene, 1,2,4-trimethylbenzene, tetraline, indan, anisole, 2-methylanisole, 3-methylanisole, 2,3-dimethylanisole, 3,4-dimethylanisole, 2,6-dimethylanisole, ethyl Phenyl ether, butyl phenyl ether, 1,2-methylenedioxybenzene, 1,2-ethylenedioxybenzene, 1,2-dichlorobenzene, 1,3-dichlorobenzene, and 1,4-dichlorobenzene are more preferable. Benzene, o-xylene, mesityrene, tetralin, indan, anisole, 2-methylanisole, 3-methylaniso R, 2,3-dimethylanisole, 3,4-dimethylanisole, 2,6-dimethylanisole.

As the solvent used in the present invention, one type of solvent can be used alone, or two or more types of solvents having different properties such as boiling point, polarity, and solubility parameter can be mixed and used.

The temperature at which the heteroacene derivative represented by the general formula (1) is mixed and dissolved in a solvent is preferably in the temperature range of 0 to 80 ° C., preferably in the temperature range of 10 to 60 ° C. for the purpose of promoting dissolution. It is more preferable to carry out with.

Further, the time for dissolving and mixing the heteroacene derivative represented by the general formula (1) in an organic solvent is preferably 1 minute to 1 hour in order to obtain a uniform solution.

In the present invention, when the concentration of the heteroacene derivative represented by the general formula (1) in the solution for forming an organic semiconductor layer of the present invention is in the range of 0.1 to 10.0% by weight, it becomes easy to handle and the organic semiconductor layer can be formed. It will be more efficient in forming. Further, when the viscosity of the solution for forming an organic semiconductor layer is in the range of 0.3 to 10 mPa · s, more suitable coatability is exhibited.

Since the heteroacen derivative itself has appropriate cohesiveness, the solution can be prepared at a relatively low temperature, and since it has oxidation resistance, it can be suitably applied to the production of an organic thin film by a coating method. .. That is, since it is not necessary to remove air from the atmosphere, the coating process can be simplified. Further, the solution may contain a polymer such as polystyrene, poly (α-methylstyrene), polyvinylnaphthalene, ethylene-norbornene copolymer, polyphenylene ether, polymethylmethacrylate or the like as a binder. The concentration of these polymer binders is preferably 0.1 to 10.0% by weight because of the appropriate viscosity of the solution.

The coating method for forming the organic semiconductor layer using the solution for forming the organic semiconductor layer of the present invention is not particularly limited as long as it can form the organic semiconductor layer, and is, for example, spin coating, drop casting, or dipping. Simple coating methods such as coating and cast coating; printing methods such as dispenser, inkjet, slit coating, blade coating, flexo printing, screen printing, gravure printing, offset printing, etc. can be mentioned, and among them, easily and efficiently with organic semiconductor layers. Spin coating, drop casting, inkjet, and flexo printing are preferable because they can be used.

An organic semiconductor layer can be formed by applying the solution for forming an organic semiconductor layer of the present invention and then drying and removing the solvent.

When the solvent is dried and removed from the coated organic semiconductor layer, the drying conditions are not particularly limited, and for example, the solvent can be dried and removed under normal pressure or reduced pressure.

The temperature at which the organic solvent is dried and removed from the coated organic semiconductor layer is not particularly limited, but the organic solvent can be efficiently dried and removed from the coated organic semiconductor layer, and the organic semiconductor layer can be formed. , Preferably in the temperature range of 10 to 150 ° C.

When the organic solvent is dried and removed from the coated organic semiconductor layer, the crystal growth of the heteroacene derivative represented by the general formula (1) can be controlled by adjusting the vaporization rate of the organic solvent to be removed.

The film thickness of the organic semiconductor layer formed by the solution for forming an organic semiconductor layer of the present invention is not limited, and good carrier transfer can be obtained. Therefore, the range is preferably 1 nm to 1 μm, and 10 nm to 300 nm. Is more preferable.

Further, the obtained organic semiconductor layer may be annealed at 40 to 180 ° C. after forming the organic semiconductor layer.

The organic semiconductor layer formed from the organic semiconductor layer forming solution of the present invention can be used as an organic semiconductor layer of an organic semiconductor device, particularly an organic thin film transistor.

The organic thin film can be obtained by laminating an organic semiconductor layer having a source electrode and a drain electrode attached on the substrate and a gate electrode via an insulating layer, and is used for forming the organic semiconductor layer of the present invention on the organic semiconductor layer. By using the organic semiconductor layer formed by the solution, it is possible to obtain an organic thin film exhibiting excellent semiconductor and electrical characteristics.

FIG. 1 shows a structure of a general organic thin film transistor based on the cross-sectional shape. Here, (A) is a bottom gate-top contact type, (B) is a bottom gate-bottom contact type, (C) is a top gate-top contact type, and (D) is a top gate-bottom contact type. 1 is an organic semiconductor layer, 2 is a substrate, 3 is a gate electrode, 4 is a gate insulating layer, 5 is a source electrode, and 6 is a drain electrode, which are formed from the organic semiconductor layer forming solution of the present invention. The organic semiconductor layer to be formed can be applied to any organic thin film transistor.

The substrate according to the present invention is not particularly limited, and for example, polyethylene terephthalate, polyethylene naphthalate, polymethylmethacrylate, polymethylacrylate, polyethylene, polypropylene, polystyrene, cyclic polyolefin, fluorinated cyclic polyolefin, polyimide, polycarbonate, polyvinylphenol, Plastic substrates such as polyvinyl alcohol, poly (diisopropyl fumarate), poly (diethyl fumarate), poly (diisopropyl maleate), polyether sulfone, polyphenylene sulfide, cellulose triacetate; glass, quartz, aluminum oxide, silicon, high-doped silicon , Inorganic material substrates such as silicon oxide, tantalum dioxide, tantalum pentoxide, indium tin oxide; metal substrates such as gold, copper, chromium, titanium and aluminum. When high-doped silicon is used for the substrate, the substrate can also serve as a gate electrode.

The gate electrode according to the present invention is not particularly limited, and for example, aluminum, gold, silver, copper, high-doped silicon, tin oxide, indium oxide, indium tin oxide, chromium, titanium, tantalum, graphene, carbon nanotubes and the like. Inorganic materials; organic materials such as doped conductive polymers (eg PEDOT-PSS) can be mentioned.

Further, the above-mentioned inorganic material can be used as a metal nanoparticle ink without any problem. The solvent used as a metal nanoparticles ink is a polar solvent such as water, methanol, ethanol, 2-propanol, 1-butanol, 2-butanol, etc. for moderate dispersibility; hexane, heptane, octane, decane, dodecane, An aliphatic hydrocarbon solvent having 6 to 14 carbon atoms such as tetradecane; toluene, xylene, mesityrene, ethylbenzene, pentylbenzene, hexylbenzene, octylbenzene, cyclohexylbenzene, tetraline, indan, anisole, 1,2-dimethoxybenzene, 1, It is preferably an aromatic hydrocarbon solvent having 7 to 14 carbon atoms such as 3-dimethoxybenzene, 1,2-dimethylanisole, 2,3-dimethylanisole and 3,4-dimethylanisole. After applying the nanoparticle ink, it is preferable to perform annealing treatment in a temperature range of 80 ° C. to 200 ° C. in order to improve conductivity.

The gate insulating layer according to the present invention is not particularly limited, and for example, silicon oxide, silicon nitride, aluminum oxide, aluminum nitride, titanium oxide, tantalum dioxide, tantalum pentoxide, indium tin oxide, tin oxide, vanadium oxide, and titanium oxide. Inorganic materials such as barium acid acid, bismuth titanate; polymethylmethacrylate, polymethylacrylate, polyimide, polycarbonate, polyvinylphenol, polyvinyl alcohol, poly (diisopropylfumarate), poly (diethylfumarate), polyethylene terephthalate, polyethylene naphthalate, Ethyl polysilicate, methyl polysilicate, ethyl polycrotonate, polyethersulfone, polypropylene-co-1-butene, polyisobutylene, polypropylene, polycyclopentane, polycyclohexane, polycyclohexane-ethylene copolymer, polyfluorine Cyclopentane, polyfluorinated cyclohexane, polyfluorinated cyclohexane-ethylene copolymer, parylene C, polyimide resin, BCB resin (trade name: Cycloten, manufactured by Dow Chemical Co., Ltd.), Cytop ™, Teflon ™ The polymer insulating material (polymer gate insulating layer) to which the coating method can be applied is preferable because the production method is simple.

The solvent used to dissolve the polymer insulating material is not particularly limited, and for example, an aliphatic hydrocarbon solvent having 6 to 14 carbon atoms such as hexane, heptane, octane, decane, dodecane, and tetradecane; THF, 1,2- Ether-based solvents such as dimethoxyethane and dioxane; alcohol-based solvents such as ethanol, isopropyl alcohol, 1-butanol, 2-butanol and 2-ethylhexanol; ketone solvents such as acetone, methyl ethyl ketone, diethyl ketone, diisopropyl ketone and acetophenone; Ester solvents such as ethyl acetate, γ-butyrolactone, cyclohexanol acetate, 3-methoxybutyl acetate; amide solvents such as DMF and NMP; dipropylene glycol dimethyl ether, dipropylene glycol diacetate, dipropylene glycol methyl-n-propyl Ether, Dipropylene glycol methyl ether acetate, 1,4-butanediol diacetate, 1,3-butylene glycol diacetate, 1,3-butylene glycol diacetate, 1,6-hexanediol diacetate, ethylene glycol monomethyl ether acetate , Propropylene glycol monomethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate and other glycol solvents; perfluorohexane, perfluorooctane, 2- (pentafluoroethyl) hexane, 3- (penta) Fluorinated solvents such as fluoroethyl) heptane can be mentioned.

The concentration of the polymer insulating material is, for example, 0.1 to 10.0% by weight at a temperature of 20 to 40 ° C. The film thickness of the insulating layer obtained at this concentration is not limited, and is preferably 100 nm to 1 μm, more preferably 150 nm to 900 nm from the viewpoint of insulation resistance.

The surfaces of these gate insulating layers are, for example, octadecyltrichlorosilane, decyltrichlorosilane, decyltrimethoxysilane, octyltrichlorosilane, octadecyltrimethoxysilane, β-phenethyllichlorosilane, β-phenetyltrimethoxysilane, and phenyltri. Silanes such as chlorosilane and phenyltrimethoxysilane; even those modified with phosphonic acids such as octadecylphosphonic acid, decylphosphonic acid and octylphosphonic acid, and silylamines such as hexamethyldisilazane can be used. Generally, by surface-treating the gate insulating layer, it is preferable to improve the carrier mobility, the current on / off ratio, and the threshold voltage in order to increase the crystal grain size and the molecular orientation of the organic semiconductor material. The result is obtained.

The material of the source electrode and the drain electrode of the organic thin film transistor of the present invention is not particularly limited, and the same material as the gate electrode can be used, and the material may be the same as or different from that of the gate electrode. May be laminated. In addition, surface treatment can be performed on these electrode materials in order to increase the efficiency of carrier injection. Examples of the expression treatment agent used for the surface treatment include benzenethiol, pentafluorobenzenethiol, 4-fluorobenzenethiol, 4-methoxybenzenethiol and the like.

The organic thin film transistor of the present invention preferably has a carrier mobility of 0.1 cm ² / V · s or more because of its high operability. Moreover, because of the high switching characteristics, current on-off ratio, is preferably 1.0 × 10 ⁶ or more.

The organic semiconductor material of the present invention is used for organic semiconductor layers of transistors such as electronic papers, organic EL displays, liquid crystal displays, IC tags (RFID tags), pressure sensors, and biosensors; organic EL display materials; organic semiconductor laser materials; organic. Thin-film solar cell material; It can be used as an electronic material such as a photonic crystal material, and since the heteroacene derivative represented by the general formula (1) becomes a crystalline thin film, it can be used as a semiconductor layer application for an organic thin film transistor. preferable.

The novel heteroacene derivative of the present invention provides high carrier mobility, high heat resistance, high oxidation resistance, and appropriate solubility, and thus provides an organic thin film transistor that exhibits excellent semiconductor properties by coating. It is possible, and the effect is extremely high.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

¹ H NMR spectrum, gas chromatographic fluffy-mass spectrum (GCMS), and liquid chromatography-mass spectrum (LCMS) analysis were used to identify the products.

< ^{1 1} H NMR spectrum analysis>
Equipment: JEOL Ltd. (trade name) Delta V5 (400MHz)
<Gas Chromatography-Mass Spectrum Analysis>
Equipment: PerkinElmer, (trade name) Auto System XL (MS section; Turbo Mass Gold)
Column; manufactured by J & W Scientific Co., Ltd. (trade name) DB-1,30 m.
MS ionization; electron impact (EI) method (70 electron volt)
<Liquid Chromatography-Mass Spectrum (LCMS) Analysis>
Equipment; Bruker Daltonics, (trade name) microTOF focus
MS ionization; atmospheric pressure chemical ionization (APCI) method column; manufactured by Tosoh, ODS-100V, 5 μm, 4.6 mm × 250 mm
Eluent; Dichloromethane: Acetonitrile = 2: 8 (volume ratio)
Flow rate; 1.0 ml / min
Detection conditions; UV detection (254 nm)
Gas chromatography (GC) and liquid chromatography (LC) analysis were used to confirm the progress of the reaction.

<Gas chromatography analysis>
Equipment: Shimadzu Corporation, (trade name) GC14B
Column; manufactured by J & W Scientific, (trade name) DB-1,30m
Liquid chromatography analysis was used to measure the purity of the heteroacene derivative.

<Liquid chromatography analysis>
Equipment: Made by Tosoh (Controller: PX-8020, Pump; CCPM-II, Degasser; SD-8022)
Column: Made by Tosoh, (trade name) ODS-100V, 5 μm, 4.6 mm x 250 mm
Column temperature; 33 ° C
Eluent; Dichloromethane: Acetonitrile = 2: 8 (volume ratio)
Flow rate; 1.0 ml / min
Detector; UV (manufactured by Tosoh, (trade name) UV-8020, wavelength; 254 nm).

Synthesis Example 1 (Synthesis of 1,8-dichloronaphthalene-2,7-diol) (Step (A))
Under a nitrogen atmosphere, 992 mg (6.20 mmol) of 2,7-dihydroxynaphthalene (Tokyo Chemical Industry) and 60 mL of acetonitrile (dehydration grade) were added to a 200 mL three-necked flask. This solution was cooled to 0 ° C., and 1.74 g (13.0 mmol) of N-chlorosuccinimide (Tokyo Chemical Industry) was added. The obtained mixture was stirred at room temperature for 5 hours, and the reaction was stopped by adding 60 mL of hydrochloric acid. Extracted with dichloromethane, the organic phase was washed with brine and dried over anhydrous sodium sulfate. The mixture was concentrated under reduced pressure, and the obtained residue was purified by silica gel column chromatography (developing solvent: dichloromethane) to obtain 1.06 g of 1,8-dichloronaphthalene-2,7-diol (yield 75%).
Synthesis Example 2 (Synthesis of 1,8-dichloro-2,7-bis (trifluoromethanesulfonyloxy) naphthalene) (Step (B))
Under a nitrogen atmosphere, 1.01 g (4.40 mmol) of 1,8-dichloronaphthalene-2,7-diol obtained in Synthesis Example 1 and 20 mL of pyridine (dehydration grade) were added to a 100 mL two-necked flask. This solution was cooled to 0 ° C., 1.58 mL (9.68 mmol) of trifluoromethanesulfonic anhydride (Tokyo Chemical Industry) was added, and the mixture was stirred for 24 hours while raising the temperature to room temperature. After cooling the reaction solution to 0 ° C., the reaction was stopped by adding 30 mL of hydrochloric acid. Extracted with dichloromethane, the organic phase was washed with brine and dried over anhydrous sodium sulfate. The mixture was concentrated under reduced pressure, and the obtained residue was purified by silica gel column chromatography to obtain 2.06 g of 1,8-dichloro-2,7-bis (trifluoromethanesulfonyloxy) naphthalene (yield 95%).

Synthesis Example 3 (Synthesis of 2,7-di (3-bromothienyl-2-) -1,8-dichloronaphthalene) (step (C))
Under a nitrogen atmosphere, 2.18 g (9.00 mmol) of 2,3-dibromothiophene (Tokyo Chemical Industry) and 40 ml of THF (dehydration grade) were added to a 100 ml Schlenk reaction vessel. The solution was cooled to 0 ° C. and 4.60 ml (9.20 mmol) of a THF solution of ethylmagnesium chloride (Sigma-Aldrich, 2.0 M) was added dropwise. The mixture was aged at 0 ° C. for 1 hour (preparation of Grignard reagents). On the other hand, under a nitrogen atmosphere, 1.36 g (10.0 mmol) of zinc chloride (Wako Pure Chemical Industries, Ltd.) and 20 ml of THF (dehydration grade) were added to another 200 ml Schlenk reaction vessel, and the mixture was cooled to 0 ° C. The Grignard reagent of 2,3-dibromothiophene prepared above was added dropwise to the obtained white fine slurry solution using a Teflon cannula, and further, a 100 ml Schlenk reaction vessel and Teflon using 5 ml of THF (dehydration grade) were used. The cannula was added while cleaning. The resulting mixture was stirred at 0 ° C. for 30 minutes and further at room temperature for 1 hour. 1.48 g (3.00 mmol) of 1,8-dichloro-2,7-bis (trifluoromethanesulfonyloxy) naphthalene obtained in Synthesis Example 2 was added to the white fine slurry of the produced 3-bromothienyl-2-zinc derivative. And as a catalyst, tetrakis (triphenylphosphine) palladium (Tokyo Chemical Industry) 52.0 mg (0.0448 mmol, 1.50 mol% with respect to 1,8-dichloro-2,7-bis (trifluoromethanesulfonyloxy) naphthalene). Was added. After carrying out the reaction at 50 ° C. for 20 hours, the container was cooled with water and 100 ml of 1N hydrochloric acid was added to stop the reaction. The mixture was extracted with toluene, the organic phase was washed with brine, and dried over anhydrous sodium sulfate. The mixture was concentrated under reduced pressure, and the obtained residue was purified by silica gel column chromatography (developing solvent: toluene). The mixture was concentrated under reduced pressure, and the obtained residue was washed with 20 ml of hexane. The obtained residue was recrystallized from heptane / toluene = 2/1 to obtain 638 mg of 2,7-di (3-bromothienyl-2-) -1,8-dichloronaphthalene (yield 41%).

Example 1 (Synthesis of unsubstituted heteroacene (Compound 1)) (Step (D))
Under a nitrogen atmosphere, 836 mg (3.48 mmol) of sodium sulfide / 9 hydrate (Wako Pure Chemical Industries, Ltd.) and 60 ml of NMP were added to a 300 ml three-necked flask. Water generated from the system was removed while heating at 160 ° C. for 1 hour, and the mixture was cooled to room temperature. To this, 602 mg (1.16 mmol) of 2,7-di (3-bromothienyl-2-) -1,8-dichloronaphthalene obtained in Synthesis Example 3 was added. The resulting mixture was heated at 170 ° C. for 5 hours and then cooled to room temperature. Under ice cooling, 120 ml of water was added to the reaction mixture, and the precipitated solid was filtered. The solid was washed with water, methanol and hexane to give 184 mg of unsubstituted heteroacene (yield 45%).

Example 2 (Synthesis of diacyl heteroacene) (Step (E))
To a 200 ml three-necked flask, 160 mg (0.454 mmol) of the unsubstituted heteroacene synthesized in Example 1 and 40 ml of dichloromethane (dehydrated grade) were added. The mixture was ice-cooled and 211 mg (1.58 mmol) of aluminum chloride (Wako Pure Chemical Industries, Ltd.) and 183 mg (1.36 mmol) of hexanoyl chloride (sigma-Aldrich) were added. The obtained mixture was stirred at room temperature for 39 hours, cooled with ice, and 100 ml of water was added to stop the reaction. The resulting mixture was heated and dichloromethane was distilled off. The obtained yellow slurry liquid was filtered, and the yellow solid was washed with water, 1M hydrochloric acid, water, and methanol in this order, and then dried under reduced pressure to obtain 224 mg of diacyl heteroacene (yield 90%).

Example 3 (Synthesis of heteroacene derivative (Compound 4)) (Step (F))
Under a nitrogen atmosphere, 201 mg (0.366 mmol) of diacyl heteroacene synthesized in Example 2 and 30 ml of THF (dehydration grade) were added to a 100 ml three-necked flask. The mixture was ice-cooled and added in the order of aluminum chloride (Wako Pure Chemical Industries, Ltd.) 244 mg (1.83 mmol) and sodium borohydride (Wako Pure Chemical Industries, Ltd.) 138 mg (3.66 mmol). The mixture was stirred under heating under reflux for 5 hours, then cooled with water and 30 ml of water was added to stop the reaction. The mixture was extracted with toluene, the organic phase was washed with 1M hydrochloric acid and saturated brine, and dried over anhydrous sodium sulfate. The mixture was concentrated under reduced pressure, the obtained residue was purified by silica gel column chromatography (developing solvent: hexane / toluene = 2/1), and the obtained compound was recrystallized from toluene three times to obtain a heteroacene derivative (compound 4). Crystals of 57.2 mg were obtained (yield 30%).

Example 4 (Synthesis of diacyl heteroacene) (Step (E))
Diacyl heteroacene was obtained in a yield of 92% by the same method as in Example 2 except that butyryl chloride (sigma-aldrich) was used instead of hexanoyl chloride used in Example 2.

Example 5 (Synthesis of heteroacene derivative (Compound 2)) (Step (F))
A heteroacene derivative (Compound 2) was obtained in a yield of 30% by the same method as in Example 3 except that the diacyl heteroacene synthesized in Example 4 was used instead of the diacyl heteroacene synthesized in Example 2. It was.

Example 6 (Synthesis of diacyl heteroacene) (Step (E))
A yellow solid of diacyl heteroacene was obtained in a yield of 83% by the same method as in Example 2 except that octanoyl chloride (sigma-aldrich) was used instead of hexanoyl chloride used in Example 2.

Example 7 (Synthesis of heteroacene derivative (Compound 6)) (Step (F))
Yield of pale yellow crystals of the heteroacene derivative (Compound 6) by the same method as in Example 3 except that the diacyl heteroacene synthesized in Example 6 was used instead of the diacyl heteroacene synthesized in Example 2. Obtained at 40%.

Synthesis Example 4 (Synthesis of 2,7-di (2-chlorothienyl-3-) -1,8-dichloronaphthalene) (step (C-2))
Under a nitrogen atmosphere, 1.62 g (8.22 mmol) of 3-bromo-2-chlorothiophene (Tokyo Chemical Industry) and 30 ml of THF (dehydration grade) were added to a 100 ml Schlenk reaction vessel. The solution was cooled to 0 ° C. and 4.30 ml (8.60 mmol) of a THF solution of isopropylmagnesium chloride (Sigma-Aldrich, 2.0 M) was added dropwise. The mixture was aged at 0 ° C. for 1 hour (preparation of Grignard reagents). On the other hand, in a nitrogen atmosphere, 1.23 g (9.02 mmol) of zinc chloride (Wako Pure Chemical Industries, Ltd.) and 10 ml of THF (dehydration grade) were added to another 200 ml Schlenk reaction vessel, and the mixture was cooled to 0 ° C. The Grignard reagent of 3-bromo-2-chlorothiophene prepared above was added dropwise to the obtained white fine slurry solution using a Teflon cannula, and further, a 100 ml Schlenk reaction vessel was used using 5 ml of THF (dehydration grade). And the Teflon cannula was added while washing. The resulting mixture was stirred at 0 ° C. for 30 minutes and further at room temperature for 90 minutes. 1.35 g (2.74 mmol) of 1,8-dichloro-2,7-bis (trifluoromethanesulfonyloxy) naphthalene obtained in Synthesis Example 2 was added to the white microslurry of the produced 2-chlorothienyl-3-zinc derivative. And as a catalyst, tetrakis (triphenylphosphine) palladium (Tokyo Chemical Industry) 47.5 mg (0.0411 mmol, 1.50 mol% with respect to 1,8-dichloro-2,7-bis (trifluoromethanesulfonyloxy) naphthalene). Added. After carrying out the reaction at 50 ° C. for 8 hours, the container was cooled with water and 100 ml of 1N hydrochloric acid was added to stop the reaction. The mixture was extracted with toluene, the organic phase was washed with brine, and dried over anhydrous sodium sulfate. The mixture was concentrated under reduced pressure, and the obtained residue was purified by silica gel column chromatography (developing solvent: toluene). The mixture was concentrated under reduced pressure, and the obtained residue was washed with 20 ml of hexane. The obtained residue was recrystallized from heptane / toluene = 2/1 to obtain 648 mg of 2,7-di (2-chlorothienyl-3-) -1,8-dichloronaphthalene (yield 55%). ..

Example 8 (Synthesis of unsubstituted heteroacene (Compound 8)) (Step (D-2))
Instead of 2,7-di (3-bromothienyl-2-) -1,8-dichloronaphthalene synthesized in Synthesis Example 3, 2,7-di (2-chlorothienyl-3-3) synthesized in Synthesis Example 4 )-1,8-Dichloronaphthalene was used, and the same method as in Example 1 was used to obtain unsubstituted heteroacene (Compound 8) in a yield of 65%.

Example 9 (Synthesis of diacyl heteroacene) (Step (E-2))
The diacyl heteroacene was collected by the same method as in Example 2 except that the unsubstituted heteroacene (Compound 8) synthesized in Example 8 was used instead of the unsubstituted heteroacene (Compound 1) synthesized in Example 1. Obtained at a rate of 89%.

Example 10 (Synthesis of heteroacene derivative (Compound 11)) (Step (F-2))
The yield of pale yellow crystals of the heteroacene derivative (Compound 11) was obtained by the same method as in Example 3 except that the diacyl heteroacene synthesized in Example 9 was used instead of the diacyl heteroacene synthesized in Example 2. Obtained at 34%.

Example 11 (Synthesis of diacyl heteroacene) (Step (E-2))
Diacyl heteroacene was obtained in a yield of 91% by the same method as in Example 9 except that butyryl chloride (sigma-aldrich) was used instead of hexanoyl chloride used in Example 9.

Example 12 (Synthesis of Heteroacene Derivative (Compound 9)) (Step (F-2))
A heteroacene derivative (Compound 9) was obtained in a yield of 25% by the same method as in Example 10 except that the diacyl heteroacene synthesized in Example 11 was used instead of the diacyl heteroacene synthesized in Example 9. It was.

Example 13 (Synthesis of Diacyl Heteroacene) (Step (E-2))
Diacyl heteroacene was obtained in a yield of 85% by the same method as in Example 9 except that octanoyl chloride (sigma-aldrich) was used instead of hexanoyl chloride used in Example 9.

Example 14 (Synthesis of heteroacene derivative (Compound 13)) (Step (F-2))
A heteroacene derivative (Compound 13) was obtained in a yield of 40% by the same method as in Example 10 except that the diacyl heteroacene synthesized in Example 13 was used instead of the diacyl heteroacene synthesized in Example 9. It was.

Example 15
(Preparation of solution for forming organic semiconductor layer)
Under air, 1.80 mg of the heteroacene derivative (Compound 4) obtained in Example 3 and 874 mg of toluene (Wako Pure Chemical Industries, Ltd., Pure Grade) were added to a 10 ml sample tube and heated to 40 ° C. to prepare a solution (0). .20% by weight). The purity of this compound was 99.1% by liquid chromatography. When the solution was brought into contact with the outside air, stirred at 70 ° C., and then analyzed by liquid chromatography, no decrease in purity was observed, and it was confirmed that the solution had oxidation resistance.

(Preparation of organic semiconductor layer)
On an n-type high-doped silicon substrate (Miyoshi, resistance value; 0.004 Ω, with a 200 nm silicon oxide film on the surface) under air, 0.5 ml of the obtained solution was filled in a syringe, and 0 The solution passed through a .2 μm filter was drop cast. It was naturally dried at room temperature (25 ° C.) to prepare an organic thin film (organic semiconductor layer) of a heteroacene derivative (compound 4) having a film thickness of 54 nm.

(Manufacturing of organic thin film transistor)
A shadow mask having a channel length of 40 μm and a channel width of 500 μm was placed on the organic thin film, and an electrode was formed by vacuum-depositing gold to prepare a bottom gate-top contact type p-type organic thin film transistor.

Using a semiconductor parameter analyzer (Caseley 4200SCS), the electrical properties of the produced organic thin film transistor are scanned with a drain voltage (Vd = -80V) and the gate voltage (Vg) from +5 to -80V in 1V increments to evaluate the transfer characteristics. Was done. Carrier mobility of holes 0.16cm ² / V · s, the current on-off ratio was 2.5 × 10 ^7.

Further, the electrical properties of this organic thin film transistor after being annealed at 150 ° C. for 15 minutes were measured. Carrier mobility of holes 0.14cm ² / V · s, the current on-off ratio was 1.7 × 10 ^7, was hardly observed performance degradation due to heat treatment.

Example 16
(Preparation of solution for forming organic semiconductor layer)
Under air, 1.76 mg of the heteroacene derivative (Compound 11) obtained in Example 10 and 870 mg of toluene (Wako Pure Chemical Industries, Ltd., Pure Grade) were added to a 10 ml sample tube and heated to 40 ° C. to prepare a solution (0). .10% by weight). The purity of this compound was 99.1% by liquid chromatography. When the solution was brought into contact with the outside air, stirred at 70 ° C., and then analyzed by liquid chromatography, no decrease in purity was observed, and it was confirmed that the solution had oxidation resistance.

(Preparation of organic semiconductor layer)
On an n-type high-doped silicon substrate (Miyoshi, resistance value; 0.004 Ω, with a 200 nm silicon oxide film on the surface) under air, 0.5 ml of the obtained solution was filled in a syringe, and 0 The solution passed through a .2 μm filter was drop cast. It was naturally dried at room temperature (25 ° C.) to prepare an organic thin film (organic semiconductor layer) of a heteroacene derivative (compound 11) having a film thickness of 54 nm.

(Manufacturing of organic thin film transistor)
A shadow mask having a channel length of 40 μm and a channel width of 500 μm was placed on the organic thin film, and an electrode was formed by vacuum-depositing gold to prepare a bottom gate-top contact type p-type organic thin film transistor.

Using a semiconductor parameter analyzer (Caseley 4200SCS), the electrical properties of the produced organic thin film transistor are scanned with a drain voltage (Vd = -80V) and the gate voltage (Vg) from +5 to -80V in 1V increments to evaluate the transfer characteristics. Was done. Carrier mobility of holes 0.18cm ² / V · s, the current on-off ratio was 2.2 × 10 ^7.

Further, the electrical properties of this organic thin film transistor after being annealed at 150 ° C. for 15 minutes were measured. Carrier mobility of holes 0.15cm ² / V · s, the current on-off ratio was 1.5 × 10 ^7, was hardly observed performance degradation due to heat treatment.

Comparative Example 1
(Preparation of organic semiconductor layer)
Under air, 1.5 mg of din-octylbenzothienobenzothiophene (Sigma-Aldrich) and 750 mg of toluene (Wako Pure Chemical Industries, Ltd., Pure Grade) were added to a 10 ml sample tube, and the solution was prepared by heating at 40 ° C. ( 0.20% by weight).

0.5 ml of the obtained solution was placed in a syringe on a 2-inch diameter n-type high-doped silicon substrate (Miyoshi, resistance value; 0.001 to 0.004 Ω, with a 200 nm silicon oxide film on the surface) under air. The solution was filled and passed through a 0.2 μm filter and dropped cast. It was air-dried at room temperature (25 ° C.) to prepare an organic thin film (organic semiconductor layer) of din-octylbenzothienobenzothiophene having a film thickness of 58 nm.

(Manufacturing of organic thin film transistor)
A bottom gate-top contact type p-type organic thin film transistor was produced by the same method as in Example 15.

Carrier mobility of holes 0.10cm ² / V · s, the current on-off ratio was 2.2 × 10 ^6.

The hole carrier mobility after annealing at 150 ° C. for 15 minutes was 0.001 cm ² / V · s, and a significant decrease in performance due to heat treatment was observed. From microscopic observation, it was confirmed that the organic semiconductor thin film (organic semiconductor layer) was destroyed by heating.

Since the organic thin film transistor of the present invention provides high carrier mobility and is excellent in heat resistance and oxidation resistance, it can be expected to be applied as a semiconductor device material represented by an organic thin film transistor.

It is a figure which shows the structure by the cross-sectional shape of an organic thin film transistor.

(A): Bottom gate-top contact type organic thin film transistor (B): Bottom gate-bottom contact type organic thin film transistor (C): Top gate-top contact type organic thin film transistor (D): Top gate-bottom contact type organic thin film transistor 1: Organic semiconductor layer 2: Substrate 3: Gate electrode 4: Gate insulating layer 5: Source electrode 6: Drain electrode

Claims (6)

A heteroacene derivative represented by the following general formula (1).

(Here, R ^{1 to} R ⁴ are independently hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms, an acyl group having 1 to 20 carbon atoms, an aryl group having 4 to 22 carbon atoms, and 2 carbon atoms. It represents an alkenyl group of ~ 20 or an alkynyl group having 2 to 20 carbon atoms. T ¹ and T ² independently represent a sulfur atom, an oxygen atom, or a selenium atom, and rings A and B are independent of each other. It is a 5-membered ring and shows the structures represented by the following general formulas (A) and (B), respectively).

(Here, R ^{5 to} R ⁸ are independently hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms, an acyl group having 1 to 20 carbon atoms, an aryl group having 4 to 22 carbon atoms, and 2 carbon atoms, respectively. It represents an alkenyl group of ~ 20 or an alkynyl group having 2 to 20 carbon atoms. T ³ and T ⁴ independently represent a sulfur atom, an oxygen atom, and a selenium atom, respectively.) The heteroacene derivative according to claim 1, wherein the substituents R ^{1 to} R ⁴ , R ⁶ and R ⁸ are hydrogen, and T ^{1 to} T ⁴ are sulfur atoms. The heteroacene derivative according to claim 1 or 2, wherein the heteroacene derivative represented by the general formula (1) is represented by the following general formula (1-1) or the following general formula (1-2).

(Here, R ^{1 to} R ⁸ and T ^{1 to} T ⁴ have the same meaning as the substituent represented by the general formula (1) according to claim 1.) A solution for forming an organic semiconductor layer, which is obtained by dissolving the heteroacene derivative according to any one of claims 1 to 3 in a solvent. An organic semiconductor layer obtained by using the solution for forming an organic semiconductor layer according to claim 4. An organic thin film transistor obtained by using the organic semiconductor layer according to claim 5.

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