JP6220612B2 - Compound, composition, organic semiconductor material, and organic thin film transistor - Google Patents

Description

  The present invention relates to an organic semiconductor material and an organic thin film transistor.

Conventionally, a thin film transistor (TFT) using amorphous silicon or polycrystalline silicon has been widely used as a switching element for liquid crystal display devices, organic EL display devices and the like. However, these TFTs using silicon cannot be developed on a plastic substrate having poor heat resistance because the manufacturing equipment is expensive and the film is formed at a high temperature. In order to solve this problem, an organic TFT using an organic semiconductor as a channel semiconductor layer instead of a silicon semiconductor has been proposed.

  Since organic semiconductors can be used as a solution and can be printed at low temperatures, they do not require large-scale manufacturing equipment and can be applied to plastics with poor heat resistance, leading to flexible electronics and other flexible electronics. That is expected. On the other hand, organic semiconductors have lower carrier mobility than silicon semiconductors, and as a result, the response speed of TFTs has been a problem for practical use. Recently, organic semiconductors with the same mobility as amorphous silicon have been developed. It has been.

For example, Patent Document 1 discloses 2,7-substituted [1] benzothieno [3,2-b] [1] benzothiophene skeleton (hereinafter referred to as [1] benzothieno [3,2-b] [1] benzothiophene. compounds having abbreviated as BTBT) are described, as a substituent, _halogen, C 1 _{-C 18} alkyl, _C 1 _{-C 18} alkyl having _halogen, C 1 _{-C 18 alkyloxy,} C 1 -C ₁₈ alkylthio, or aryl, or is aryl having _halogen, C 1 _{-C 18} alkyl, _C 1 _{-C 18} alkyl having _halogen, C 1 _{-C 18 alkyloxy,} at least one C 1 _{-C 18} alkylthio Things are listed. That the mobility of these compounds ^(cm 2 / Vs) is 0.17~0.31cm ² / Vs.

Patent Document 2 describes a compound having a 2,7-substituted BTBT skeleton, and the substituent is a hydrogen atom or a halogeno-substituted C ₁ -C ₃₆ fatty hydrocarbon group. ing. The mobility of these compounds ^(cm 2 / Vs) has been described to be 0.12~4.5cm ² / Vs.
Furthermore, Patent Document 3 has reported a compound that reaches a mobility of 5 cm ² / Vs or more by forming a semiconductor layer via a higher-order liquid crystal phase of 2-alkyl-7-aryl BTBT.

  On the other hand, as described above, although many organic semiconductor materials with improved mobility have been reported, these compounds have a substituent at a symmetric position with respect to the BTBT ring and have poor solvent solubility. There were problems such as poor storage stability of the ink and reheating of the ink during printing.

WO2006 / 077788 WO2008 / 47896 WO2012 / 121393

  An object of the present invention is to provide a novel compound having high solvent solubility, excellent ink storage stability, and practical semiconductor characteristics, and a composition thereof. Moreover, a high performance organic thin-film transistor and organic-semiconductor device are implement | achieved by providing the organic-semiconductor material and organic-semiconductor ink containing this compound.

  As a result of intensive studies, the present inventors have found that the compound A represented by any one of the following formulas (1), (2), or (3) has a substituent at an asymmetric position with respect to the ring structure. It discovered that it was excellent in solubility, and it discovered that the said subject could be solved.

・・・（１）

... (1)

・・・（２）

... (2)

・・・（３）

... (3)

(In the above formulas (1), (2), and (3), X represents any of an S atom, an O atom, and an Se atom,
R ₁ , R ₂ , R ₃ , and R ₄ each independently represent a hydroxyl group, a thiol group, a halogen atom, or a structure represented by the following formula (4).

・・・（４）

... (4)

(In the above formula (4), Y represents an S atom, an O atom, or an NH group,
R5 represents any one of an alkylene group having 1 to 20 carbon atoms, an alkenylene group having 2 to 20 carbon atoms, an alkynylene group having 2 to 20 carbon atoms, an aromatic group, an ethynylarylene group, and an alicyclic group,
R6 represents an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, an aromatic group, an alicyclic group, or a hydrogen atom,
n represents 0 or 1. However, when n is 0, R5 is terminally substituted with a hydrogen atom. )

  Moreover, this invention solves the said subject by providing the composition containing the compound A, and the organic-semiconductor material or organic-semiconductor ink containing this composition.

  Furthermore, this invention provides the organic thin-film transistor and organic-semiconductor device which have a semiconductor layer containing this organic-semiconductor material.

  The novel compound of the present invention and the composition containing the compound are excellent in solvent solubility in various solvents, excellent in storage stability of ink, and have practical semiconductor characteristics. Suitable for manufacturing various semiconductor devices. Moreover, the organic semiconductor material containing this compound is provided, and a high-performance organic thin-film transistor and organic-semiconductor device are provided.

It is a schematic cross section of a bottom contact type transistor.

[Compound A]
The present invention provides a compound A represented by the following formula (1), (2), or (3) that is excellent as an organic semiconductor material.

・・・（１）

... (1)

・・・（２）

... (2)

・・・（３）

... (3)

(In the above formulas (1), (2), and (3), X represents any of an S atom, an O atom, and an Se atom,
R ₁ , R ₂ , R ₃ , and R ₄ each independently represent a hydroxyl group, a thiol group, a halogen atom, or a structure represented by the following formula (4).

・・・（４）

... (4)

(In the above formula (4), Y represents an S atom, an O atom, or an NH group,
R ₅ represents an alkylene group having 1 to 20 carbon atoms, an alkenylene group having 2 to 20 carbon atoms, an alkynylene group having 2 to 20 carbon atoms, an aromatic group, an ethynylarylene group, an aralkylene group, an alicyclic group,
R ₆ represents an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, an aromatic group, an alicyclic group, or a hydrogen atom,
n represents 0 or 1. However, when n is 0, R ₅ is terminally substituted with a hydrogen atom. )

  X of the compound A represented by the general formula (1), (2), or (3) of the present invention is O, S, or Se. From the viewpoint of high mobility and stability in the atmosphere, A BTBT derivative represented by S is preferred. In particular, when the BTBT has a substituent at an asymmetric position with respect to the BTBT ring at the 2-position, 6-position, 2-position and 9-position, or 2-position and 8-position, Compared with the introduced BTBT derivative, the solubility in a solvent is high, and there are many types of solvents that can be used, and the storage stability as ink is excellent, and it is suitable for semiconductor production by a printing method.

Next, the substituents R _{1 to} R ₄ of the compound A of the present invention will be described.
R _{1 to} R ₄ are a hydroxyl group, a thiol group, a halogen atom, and a substituent represented by the general formula (4). When a more specific structure of the substituent represented by the general formula (4) is exemplified, when n is 0, (A-1) an alkyl group having 1 to 20 carbon atoms, (A-2) 2 carbon atoms. -20 alkenyl group, (A-3) alkynyl group having 2-20 carbon atoms, (A-4) aromatic group, (A-5) arylethynyl group, (A-6) alicyclic group, When n is 1, (A-7) alkoxyalkyl group, (A-8) alkylsulfanylalkyl group, (A-9) alkylaminoalkyl group, (A-10) alkoxyaryl group or alkoxyalkylaryl group, (A-11) alkylsulfanylaryl group or alkylsulfanylalkylaryl group, (A-12) alkylaminoaryl group or alkylaminoalkylaryl group, (A-13) alkoxyarylene ethynyl group Alkoxyalkyl arylene ethynyl group, (A-14) alkylsulfanyl arylene ethynyl group or alkylsulfanyl alkylarylene ethynyl group, (A-15) alkylamino arylene ethynyl group or include alkylaminoalkyl arylene ethynyl group. Moreover, said substituent can have a 1-6 alkyl group or a halogen atom in a side chain.

(A-1) Examples of the alkyl group having 1 to 20 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, n-pentyl group, isopentyl group, and neopentyl group. N-hexyl group, 1-methylpentyl group, 4-methyl-2-pentyl group, 3,3-dimethylbutyl group, 2-ethylbutyl group, n-heptyl group, 1-methylhexyl group, cyclohexylmethyl group, n -Octyl group, tert-octyl group, 1-methylheptyl group, 2-ethylhexyl group, 2-propylpentyl group, n-nonyl group, 2,2-dimethylheptyl group, 2,6-dimethyl-4-heptyl group, 3,5,5-trimethylhexyl group, n-decyl group, n-undecyl group, 1-methyldecyl group, n-dodecyl group, n-tridecyl group, 1-hex Ruhepuchiru group, n- tetradecyl, n- pentadecyl, n- hexadecyl group, n- heptadecyl group, n- octadecyl group, etc. n- eicosyl group and the like,
Furthermore, a 2,2,3,3,3-pentafluoropropylene group in which some of the hydrogen atoms of these C 1-20 alkylene groups are substituted with fluorine atoms, 2,2,3,3,4, 4,4-heptafluorobutylene group, 2,2,3,3,4,4,5,5,5-nonafluoropentylene group, 2,2,3,3,4,4,5,5,6 , 6,6-undecafluorohexylene group, 2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-pentadecafluorooctylene group, etc. A halogen-substituted alkylene group can also be used.

  (A-2) Examples of the alkenyl group having 2 to 20 carbon atoms include a vinyl group, an allyl group, a butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, a decenyl group, a dodecenyl group, a tetradecenyl group, and a hexadecenyl group. , Octadecenyl group, methylpentenyl group, cyclohexene, 4-methylcyclohexene and the like, straight chain, branched and cyclic alkenyl groups.

(A-3) Examples of the alkynyl group having 2 to 20 carbon atoms that may have a substituent include ethenyl group, 1-propenyl group, 2-propenyl (propargyl) group, 1-butenyl group, and 1-pentenyl. Group, 1-hexenyl group, 1-heptenyl group, 1-octenyl group, 1-nonenyl group, 1-decenyl group, 1-undecenyl group, 1-dodecenyl group, 1-tridecenyl group, 1-tetradecenyl group, 1-pentadecenyl group Group, 1-hexadecenyl group, 1-heptadecenyl group, 1-octadecenyl group, 1-nonadecenyl group, and the like.

(A-4) The aromatic group is an aromatic hydrocarbon group having 6 to 24 carbon atoms composed of carbon and hydrogen, or a constituent atom number of 5 to 24 including an oxygen atom, a nitrogen atom, a sulfur atom, etc. in a part thereof. These may have a C1-C6 alkyl group and a halogen atom as a substituent. Examples of the aromatic hydrocarbon group which may have such a substituent include, for example, phenyl group, naphthyl group, azulenyl group, acenaphthenyl group, anthranyl group, phenanthryl group, naphthacenyl group, fluorenyl group, pyrenyl group, chrysenyl group Perylenyl group, biphenyl group, p-terphenyl group, quarterphenyl group; o-tolyl group, m-tolyl group, p-tolyl group, 2,4-xylyl group, 2,6-xylyl group, mesityl group, duryl Group, 4-ethylphenyl group, 4-n-propylphenyl group, 4-isopropylphenyl group, 4-n-butylphenyl group, 4-n-pentylphenyl group, 4-n-hexylphenyl group, 4-n- Aromatic hydrocarbon having alkyl group such as decaphenyl group, 4-stearylphenyl group, 9,9′-dihexylfluorenyl group A primary group; a 4-fluorophenylene group, a 2,6-fluorophenylene group, a 4-chlorophenylene group, a 2,3,4,5,6-perfluorophenylene group, or the like, and the arylene group is a fluorine atom, a chlorine atom, An aromatic hydrocarbon group substituted with a halogen such as a bromine atom,
Examples of the heteroaromatic group which may have a substituent include pyridinyl group, pyrrole group, thienyl group, benzothienyl group, benzoxazolyl group, benzothiazolyl group, oxadiazolyl group, dibenzooxazolyl group, dibenzothienyl Groups; heteroaromatic groups having an alkyl group such as a 2-methylthienyl group, a 2-butylthienyl group, and a 2-hexylthienyl group;

(A-5) The arylethynyl group includes, but is not limited to, a phenylethynyl group, a naphthylethynyl group, a thienylethynyl group, an oxazolylethynyl group, and the like.

Examples of the (A-6) alicyclic group include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a 4-methylcyclohexyl group, a dicyclopentanyl group, and a tricyclodecanyl group.

(A-7) As an alkoxyalkyl group, 2-ethoxyethyl group, 2-butoxyethyl group, 2-n-hexyloxyethyl group, 2-n-heptyloxyethyl group, 2-n-tetradecyloxyethyl group , 2-cyclohexyloxyethyl group, 12-ethoxydodecyl group, cyclohexyloxyethyl group and the like.

(A-8) As alkylsulfanylalkyl group, methylsulfanylpropyl group, 2-n-hexylsulfanylethyl group, 3-n-decylsulfanylpropyl group, cyclohexylsulfanylpropyl group, 8-methylsulfanyloctyl group, 8-ethyl Examples thereof include a sulfanyloctyl group, an 8-propylsulfanyloctyl group, and a 10-ethylsulfanyldecyl group.

(A-9) As the alkylaminoalkyl group, a methylaminopropyl group, 2-n-hexylaminoethyl group, 3-n-decylaminopropyl group, cyclohexylaminopropyl group, 8-methylaminooctyl group, 8-ethyl Aminooctyl group, 8-propylaminooctyl group, 10-ethylaminodecyl group and the like can be mentioned.
(A-10) As an alkoxyaryl group or alkoxyalkylaryl group, methoxyphenyl group, ethoxyphenyl group, butoxyphenyl group, 4- (2-ethoxyethyl) phenyl group, 4- (2-n-hexyloxyethyl) Phenyl group, 4- (2-n-heptyloxyethyl) phenyl group, 4- (2-n-tetradecyloxyethyl) phenyl group, 4- (2-cyclohexyloxyethyl) phenyl group, 4- (12-ethoxy) Dodecyl) phenyl group, 4- (cyclohexyloxyethyl) phenyl group, ethoxynaphthyl group, 5- (2-ethoxyethyl) thienyl group, 5- (2-n-tetradecyloxyethyl) thienyl group, 5- (2- (Cyclohexyloxyethyl) thienyl group, 5- (12-ethoxydodecyl) thienyl group, etc. It is.

(A-11) As the alkylsulfanylaryl group or alkylsulfanylalkylaryl group, 4- (methylsulfanylpropyl) phenyl group, 4- (2-n-hexylsulfanylethyl) phenyl group, 4- (3-n-decyl) Sulfanylpropyl) phenyl group, 4- (cyclohexylsulfanylpropyl) phenyl group, 5- (methylsulfanylpropyl) thienyl group, 5- (2-n-hexylsulfanylethyl) thienyl group, 5- (3-n-decylsulfanylpropyl) ) Thienyl group, 5- (cyclohexylsulfanylpropyl) thienyl group and the like.

(A-12) As the alkylamino or alkylaminoalkylaryl group, an ethylaminophenyl group, 4- (3-octylaminopropyl) phenyl group, 4- (3-dodecylaminopropyl) phenyl group, 4- (diethylaminoethyl) ) Phenyl group, 5- (3-octylaminopropyl) thienyl group, 5- (3-dodecylaminopropyl) thienyl group, 5- (diethylaminoethyl) thienyl group and the like.

(A-13) Alkoxy or alkoxyalkylarylene ethynyl groups include methoxyphenylethynyl group, ethoxyphenylethynyl group, butoxyphenylethynyl group, 4- (2-ethoxyethyl) phenylethynyl group, 4- (2-n-hexyl) Oxyethyl) phenylethynyl group, 4- (2-n-heptyloxyethyl) phenylethynyl group, 4- (2-n-tetradecyloxyethyl) phenylethynyl group, 4- (2-cyclohexyloxyethyl) phenylethynyl group 4- (12-ethoxydodecyl) phenylethynyl group, 4- (cyclohexyloxyethyl) phenylethynyl group, 5- (2-ethoxyethyl) thienylethynyl group, 5- (2-n-tetradecyloxyethyl) thienylethynyl The group 5- (2-cyclohexyl) Oxyethyl) thienylethynyl group, such as 5- (12-ethoxy-dodecyl) thienylethynyl group.

(A-14) Alkylsulfanyl or alkylsulfanylalkylaryleneethynyl group includes 4- (methylsulfanylpropyl) phenylethynyl group, 4- (2-n-hexylsulfanylethyl) phenylethynyl group, 4- (3-n- Decylsulfanylpropyl) phenylethynyl group, 4- (cyclohexylsulfanylpropyl) phenylethynyl group, 5- (methylsulfanylpropyl) thienyl group, 5- (2-n-hexylsulfanylethyl) thienylethynyl group, 5- (3-n -Decylsulfanylpropyl) thienylethynyl group, 5- (cyclohexylsulfanylpropyl) thienylethynyl group and the like.

(A-15) Alkylamino or alkylaminoalkylarylene ethynyl group includes ethylaminophenylethynyl group, 4- (3-octylaminopropyl) phenylethynyl group, 4- (3-dodecylaminopropyl) phenylethynyl group, 4 Examples include-(diethylaminoethyl) phenylethynyl group, 5- (3-octylaminopropyl) thienylethynyl group, 5- (3-dodecylaminopropyl) thienylethynyl group, 5- (diethylaminoethyl) thienylethynyl group and the like.

Among the above substituents, R ₁ of the compound A of the present invention is (A-1) an alkyl group having 1 to 20 carbon atoms, (A-7) an alkoxyalkyl group, or (A-8) an alkylsulfanylalkyl group. Are particularly preferred, and R _{2 to} R ₄ are (A-4) aromatic group, (A-5) arylethynyl group, (A-10) alkoxyaryl group or alkoxyalkylaryl group, (A-11) alkylsulfanyl. An aryl group or alkylsulfanylalkylaryl group, (A-13) alkoxyarylethynyl group or alkoxyalkylarylethynyl group, (A-14) alkylsulfanylarylethynyl group or alkylsulfanylalkylarylethynyl group is particularly preferred.

  Preferred examples of the structure of the compound A of the present invention described above include the compound examples shown in Tables 1 to 3, but are not limited thereto.

(Examples of 2,6-substituents represented by the general formula (1))

・・・（１）

... (1)

(Example of 2,9-substituted product represented by the following general formula (2))

・・・（２）

... (2)

(Examples of 2,8-substituted product represented by the following general formula (3))

・・・（３）

... (3)

[Synthesis of Compound A]
The compounds of the present invention can be obtained from Tetrahedron Letters. 2011.52. Benzofuro [3,2-b] [1] benzofuran where X = O is obtained according to the method described in 285-288, Zhurnal Organicheskoi Kimii. In accordance with the method described in 1989.25.1764-73, benzoselenopheno [3,2-b] [1] benzoselenophene with X = Se was obtained from Chemistry of Materials. 2009.21. It can synthesize | combine by the method described in 903-912. When these compounds are used as raw materials and B-8, B-21, and B-34 are taken as examples, they can be synthesized by the following known and usual schemes.

(Alkylation of BTBT)
2-alkylBTBT can be obtained by reducing carbonyl group after BTBT is subjected to Friedel-Crafts acylation reaction with acyl chloride by the method described in Liquid Crystals 31, 137-1380 (2004).
As the reaction solvent for Friedel-Crafts acylation reaction, for example, halogen solvents such as dichloromethane, chloroform, 1,1,2-trichloroethane can be used, and as the catalyst, aluminum chloride, aluminum bromide, zinc chloride, Metal halides such as iron chloride can be used.
For reduction of the acyl group, a known and commonly used reduction method such as Wolf-Kishner reduction using hydrazine or catalytic reduction with hydrogen can be applied.
Although reaction temperature does not have a restriction | limiting in particular, It is preferable from the point of reaction rate to react in the range of -70 to 100 degreeC.

(Nitration of 2-alkyl BTBT (B8-1, B21-1, B34-1))
By reacting 2-alkylated BTBT with a nitrating agent and purifying by recrystallization or silica gel column chromatography as necessary, a compound in which the 7-position, 8-position, or 9-position is nitrated is obtained. be able to.
The solvent that can be used is not particularly limited, and any solvent that does not affect the reaction, such as halogen solvents such as dichloromethane, chloroform, 1,1,2-trichloroethane, hexane, diethyl ether, and the like can be used.
As the nitrating agent, in addition to nitric acid, fuming nitric acid, mixed acid and the like, ester compounds such as butyl nitrate and nitrates such as silver nitrate can be used.
Moreover, although there is no restriction | limiting in reaction temperature, the range of -70 to 100 degreeC is preferable from the point of reaction rate.

(Amino-chlorination of B8-2)
By reacting the above 2-alkyl-7-nitroBTBT with a metal such as tin, zinc or iron, and concentrated hydrochloric acid, a compound in which the 6-position is chlorinated and the 7-position is aminated can be obtained. .
The solvent that can be used is not limited, but acetic acid is preferable from the viewpoint of reaction selectivity. Moreover, reaction temperature should just be the range of room temperature-110 degreeC, Preferably it is 70 degreeC-110 degreeC.

(Amination of B21-2 and B34-2)
By reducing the above 2-alkyl-nitro BTBT, a compound in which the 8-position or 9-position is aminated can be obtained.
For this reaction, known reduction reactions can be applied, such as catalytic reduction, reduction with metal hydrides such as lithium aluminum hydride and sodium borohydride, reduction methods using metals such as tin, zinc and iron and concentrated hydrochloric acid, etc. Is mentioned.

(Deamination of B8-3)
Deaminoated 6-chloroBTBT can be obtained by reacting the amino group of B8-3 with a nitrous acid compound to form a diazonium compound and then thermally decomposing it.
The nitrite compound is not particularly limited, and nitrites such as sodium nitrite and potassium nitrite, and nitrites such as t-butyl nitrite can be used.

(Iodination of B21-3 and B34-3)
After the amino group is diazotized with a nitrous acid compound, it can be iodinated by a Sandmeyer reaction that reacts with a metal iodide.
The nitrite compound is not particularly limited, and nitrites such as sodium nitrite and potassium nitrite, and nitrites such as t-butyl nitrite can be used. When nitrite is used, it generally reacts in an aqueous solution. When nitrite is used, in addition to halogen solvents such as dichloromethane and chloroform, known and commonly used solvents such as hexane and tetrahydrofuran are used. Can be used.
Examples of the metal iodide include, but are not limited to, copper iodide, zinc iodide, potassium iodide and the like.

(Coupling reaction (B8-4, B21-4, B34-4))
Finally, a compound A of the present invention can be obtained by a coupling reaction of the above halide with a boron compound, an allyl compound, an ethynyl compound, or a halide. As the cross-coupling reaction, known and conventional methods such as Suzuki-Miyaura coupling, Sonogami coupling, Mizorogi-Heck reaction, Kumada-Tamao coupling, etc. can be applied. Review of Chemical Review Vol. 95, 2457-2483 (1995), Chemical Review Vol. 111, 1417-1492 (2011), and cross-coupling reactions-basic and industrial applications-(CMC Publishing) The methods and conditions described in the document can be applied.

  The reaction is not particularly limited, and a known and commonly used reagent can be used, and any known and commonly used reaction temperature can be applied.

〔Composition〕
The compound A of the present invention can be applied to various uses, but may be a composition in which other materials are mixed depending on the use.

[Organic semiconductor materials]
The compound A of the present invention can be used alone or as an organic semiconductor material, but may be mixed with other known and commonly used organic semiconductor compounds or organic semiconductor polymers to form an organic semiconductor material.
Examples of such organic semiconductor compounds include polycyclic aromatic hydrocarbon compounds such as anthracene, pentacene, and rubrene; chalcogen compounds such as benzothiophene derivatives, benzoxazole derivatives, and benzoselenophene derivatives; nitrogen-containing compounds such as pyrrole derivatives and carbazole derivatives. Examples include, but are not limited to, compounds.
Examples of the organic semiconductor polymer include aromatic hydrocarbon polymers such as polyparaphenylene and polyfluorene; thiophene polymers such as polythiophene and polybenzothiophene; nitrogen-containing polymers such as polypyrrole and polycarbazole. However, it is not limited to these.
Content of the compound A of this invention in an organic-semiconductor material is 0.1-100 mass%, and in order to acquire the effect of this invention, it is preferable that it is 0.5-100 mass%.

[Organic semiconductor ink]
By dissolving the compound A of the present invention in an organic solvent, an organic semiconductor ink can be obtained.
Any organic solvent may be used, or two or more organic solvents may be mixed and used. Specifically, aliphatic solvents such as n-hexane, n-octane, n-decane and n-dodecane; alicyclic solvents such as cyclohexane; benzene, toluene, cumene, o-xylene, m-xylene, p-xylene, p-cymene, mesitylene, anisole, 2-methylanisole, 3-methylanisole, 4-methylanisole, 2,5-dimethylanisole, 3,5-dimethoxytoluene, 2,4-dimethylanisole, phenetole, Methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, 1,5-dimethyltetralin, n-propylbenzene, n-butylbenzene, n-pentylbenzene, 1,3,5-triethylbenzene, 1,3 -Dimethoxybenzene, chlorobenzene, o-dichlorobenzene, trichlorobenzene, etc. Aromatic solvents: ether solvents such as tetrahydrofuran, dioxane, ethylene glycol diethyl ether, anisole, benzyl ethyl ether, ethyl phenyl ether, diphenyl ether, methyl-t-butyl ether; methyl acetate, ethyl acetate, ethyl cellosolve, propylene glycol methyl ether Ester solvents such as acetate; alcohol solvents such as methanol, ethanol, isopropanol; ketone solvents such as acetone, methyl ethyl ketone, cyclohexanone, 2-hexanone, 2-heptanone, 3-heptanone; other dimethylformamide, dimethylsulfoxide, diethylformamide However, it is not limited to these.

The concentration of the organic semiconductor material of the present invention in the prepared liquid composition is preferably 0.01 to 20% by weight, and more preferably 0.1 to 10% by weight. One kind of organic solvent may be used, but a plurality of kinds of solvents may be mixed and used in order to obtain a desired thin film with high homogeneity.
In addition, a leveling agent such as fluorine or silicon and a polymer compound such as polystyrene or acrylic resin may be added as a viscosity modifier in order to impart ink characteristics within a range that does not impair the semiconductor performance of compound A. it can.

[Organic thin film transistor]
Next, an organic thin film transistor containing the organic semiconductor material of the present invention will be described.
Referring to the bottom contact type (a) shown in FIG. 1 as an example, 1 is a substrate, 2 is a gate electrode, 3 is a gate insulating layer, 4 is an organic semiconductor, 5 is a source electrode, and 6 is a drain electrode. The type of transistor is not limited to the illustrated structure, and there are various types depending on the arrangement of each electrode and each layer. For the type, refer to Aldrich Material Science Basics No. 6 “Basics of Organic Transistors”. be able to.

  As a board | substrate, it is comprised with glass or a flexible resin-made sheet | seat, for example, a plastic film can be used as a sheet | seat. Examples of the plastic film include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate (PC). And a film made of cellulose triacetate (TAC), cellulose acetate propionate (CAP), or the like. Thus, by using a plastic film, the weight can be reduced as compared with the case of using a glass substrate, the portability can be improved, and the resistance to impact can be improved.

The electrode material of the gate electrode, source electrode, or drain electrode is not particularly limited as long as it is a conductive material. Platinum, gold, silver, nickel, chromium, copper, iron, tin, tin oxide / antimony, indium tin oxide (ITO), fluorine-doped zinc oxide, carbon, graphite, glassy carbon, silver paste and carbon paste, lithium, beryllium, sodium, magnesium, potassium, calcium, scandium, titanium, manganese, zirconium, gallium, niobium, sodium, sodium Potassium alloy, magnesium, lithium, aluminum, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide mixture, lithium / aluminum A metal electrode such as a compound is used, but a known conductive polymer whose conductivity is improved by doping or the like, for example, conductive polyaniline, conductive polypyrrole, conductive polythiophene, a complex of polyethylenedioxythiophene and polystyrenesulfonic acid Etc. are also preferably used.

  As a method for forming an electrode, a method for forming an electrode using a known photolithographic method or a lift-off method, using a conductive thin film formed by a method such as vapor deposition or sputtering using the above as a raw material, or a metal foil such as aluminum or copper There is a method of etching using a resist by thermal transfer, ink jet or the like. Alternatively, a conductive polymer solution or dispersion, or a conductive fine particle dispersion may be directly patterned by ink jetting, or may be formed from a coating film by lithography or laser ablation. Furthermore, a method of patterning an ink containing a conductive polymer or conductive fine particles, a conductive paste, or the like by a printing method such as relief printing, intaglio printing, planographic printing, or screen printing can also be used.

Gate insulating layer is a thermoplastic resin such as parylene, polystyrene, acrylic resin, polyester resin; thermosetting resin such as epoxy resin, urethane resin, phenol resin, unsaturated polyester resin, alkyd resin, melamine resin; UV curable resin An organic thin film such as a silicon oxide film can be preferably used, but an inorganic material such as a silicon oxide film can also be used.
The gate insulating layer is formed by a spin coating method, a casting method, a dipping method, an ink jet method, a doctor blade method, a screen printing method, an offset printing method, a letterpress printing method, a reverse printing method, a micro contact printing method, a wire bar coating method, a spray coating method. The thin film can be formed by a known wet film forming method such as a dispensing method, and may be patterned into a necessary shape by a photolithographic method, if necessary.

The organic semiconductor layer can be produced by a known and common production method such as a vacuum deposition method, but the organic semiconductor layer can be easily formed by a printing method using the composition as an ink for an organic semiconductor material.
Examples of printing methods include spin coating, casting, dipping, inkjet, doctor blade, gravure printing, screen printing, offset printing, letterpress printing, reverse printing, microcontact printing, A thin film can be produced by a known wet film formation method such as a wire bar coating method, a spray coating method, or a dispensing method. Further, depending on the casting method or the like, it is possible to take a form of a flat crystal or a thick film state.

The organic transistor of the present invention can be suitably used as a switching transistor, a signal driver circuit element, a memory circuit element, a signal processing circuit element or the like of a pixel constituting a display. Examples of the display include a liquid crystal display, a dispersed liquid crystal display, an electrophoretic display, a particle rotating display element, an electrochromic display, an organic electroluminescence display, and electronic paper.

Confirmation of Operation of Organic Thin Film Transistor As shown in the examples, it is possible to confirm that the organic semiconductor material of the present invention can be used as an organic transistor by fabricating an FET and evaluating its characteristics.
For details of the semiconductor device operation confirmation by such a method, see, for example, the document S.A. F. Nelson, Y .; -Y. Lin, D.D. J. et al. Gundlach, and T.G. N. Jackson, Temperature-independent transport in high-mobility penentene transistors, Appl. Phys. Lett. , 72, no. 15 1854-1856 (1998).

[Organic semiconductor devices]
The thin film, thick film, or crystal of the organic semiconductor material of the present invention can be used not only as a semiconductor layer of the organic thin film transistor but also as a charge transporting member for various functional elements such as a photoelectric conversion element, a thin film transistor element, and a light emitting element. it can.
Applicable organic semiconductor devices include diodes, organic transistors, memories, photodiodes, light emitting diodes, light emitting transistors, sensors such as gas sensors, biosensors, blood sensors, immune sensors, artificial retinas, taste sensors, RFID, etc. Is mentioned.

  Hereinafter, an example is given and explained in detail.

Example 1 Synthesis of Compound B-21

First, BTBT (0.6 g, 0.25 mmol) was added to dichloromethane (30 mL), and the mixture was stirred until it reached −10 ° C. in a nitrogen gas atmosphere. Next, AlCl ₃ (1.35 g, 10.1 mmol) was added, and the temperature was lowered to −70 ° C. After reaching −70 ° C., Decanoyl Chloride (0.48 g, 2.5 mmol) was added dropwise over 20 minutes and stirred for 3.5 hours. After adding the reaction solution to water (60 g), CH ₂ Cl ₂ (20 g) was added and transferred to a separatory funnel. The lower layer was separated and washed twice with water (30 g), and then the organic layer was concentrated. The precipitate was dissolved in toluene (30 g) by heating and recrystallized at room temperature to obtain 0.84 g of yellow crystals of 2- (decyl-1-one) -BTBT (yield 85%).

Then 2- (decyl-1-one) -BTBT (0.8 g, 2.0 mmol), 85.5% potassium hydroxide (0.35 g, 5.3 mmol), hydrazine monohydrate (0.65 g , 12.4 mmol) was added to diethylene glycol (30 mL), stirred under a nitrogen atmosphere, heated to 100 ° C., and stirred for 1 hour. Then, it heated up to 170 degreeC, the water | moisture content was removed from the reaction system using the decanter, and it heat-stirred for 4 hours. After cooling to room temperature, the solid matter precipitated in the reaction solution was collected by filtration and washed with water and ethanol in this order. The solid after the washing was vacuum-dried at 70 degrees to obtain 0.76 g of 2-decyl-BTBT (yield 98%).

Further, 4.96 g (13 mmol) of 2-decyl-BTBT was dissolved in 320 mL of dichloromethane and then cooled to −50 ° C., and 24 mL of a 1.2 M dichloromethane solution of fuming nitric acid was added dropwise over 30 minutes. After further stirring at −50 ° C. for 2 hours, 26 mL of saturated aqueous sodium hydrogen carbonate solution was added to stop the reaction. The lower layer was separated by separation, washed with 10% brine, dried over anhydrous magnesium sulfate and concentrated to dryness to obtain a crude solid. The solid was washed with 2-butanone, and the solid obtained by concentrating the washing solution was purified by high performance liquid chromatography to obtain 367 mg of 2-decyl-9-nitroBTBT as yellow crystals (yield, 7% ).

Thereafter, 2.56 g (6 mmol) of 2-decyl-9-nitroBTBT and 1.84 g of tin powder were suspended in 30 mL of acetic acid, and 5.4 mL of concentrated hydrochloric acid was slowly added dropwise with heating and stirring at about 70 ° C. Furthermore, after reacting at 100 ° C. for 1 hour, the mixture was cooled to 10 ° C. or lower and the solid was collected by filtration. This solid was dispersed in about 100 mL of chloroform, washed sequentially with concentrated aqueous ammonia and saturated brine, dried over anhydrous magnesium sulfate, and concentrated to dryness to obtain a crude solid. This solid was separated and purified with a silica gel column (chloroform / cyclohexane = 1/1, 1% triethylamine added), recrystallized from petroleum benzine, and 1.72 g of 2-decyl-9-aminoBTBT (yield, 72%). )Obtained.

Then, 60 mL of dichloromethane was added to 1.58 g (4 mmol) of 2-decyl-9-aminoBTBT, and 864 mg of trifluoroborate / ether complex and 504 mg of t-butyl nitrite were added dropwise under cooling at −15 ° C. After raising the reaction temperature to 5 ° C. in about 1 hour, a solution of 1.6 g of iodine, 1.32 g of potassium iodide and 100 mg of tetrabutylammonium iodide in a dichloromethane-THF mixture (1: 2) 12 mL was added. The mixture was reacted for 8 hours under reflux with heating, diluted with chloroform, washed successively with 10% sodium thiosulfate, 5M sodium hydroxide, and 10% brine, dried over anhydrous sodium sulfate, and concentrated to dryness. The obtained dark brown crude solid was purified by a silica gel column (chloroform / cyclohexane = 1/1) and crystallized from chloroform-methanol. Next, recrystallization from ligroin gave 912 mg of 2-decyl-9-iodoBTBT (yield, 45%).

Finally, 253 mg (0.5 mmol) of 2-decyl-9-iodoBTBT was added to 0.11 g (0.6 mmol) of copper iodide, 0.08 g (0.1 mmol) of bis (triphenylphosphine) palladium (II) dichloride, 36 mL of triethylamine was added, and nitrogen gas was bubbled at 25 ° C. for 15 minutes. Under a nitrogen atmosphere, 0.56 g (5.4 mmol) of ethynylbenzene was added, the temperature was raised to 35 degrees, and the mixture was heated and stirred for 30 minutes. Then, after heating up to 85 degree | times, it expanded by heating for 40 hours. After cooling to room temperature, the reaction solution was added to 250 mL of water. Further, the produced solid was washed with 100 mL of acetone. After the solid was dissolved in 500 mL of cyclohexane heated to 50 ° C., 2 g of silica gel and 2 g of a metal scavenger were added to this solution to prepare a slurry. After stirring the slurry at 50 ° C. for 1 hour, the silica gel and the metal scavenger were removed by filtration and recrystallized from the filtrate to give 161 mg of white crystals of 2-decyl-9-ethynylbenzene BTBT as compound B-21. Yield, 67%).

The obtained compound B-21 was subjected to structural analysis by 1H-NMR.
1H-NMR (300 MHz, CDCl ₃ ): δ 8.02 (d, 1H, BTBT ring), 7.91 (d, 1H, BTBT ring), 7.53 (d, 1H, BTBT ring), 7.45 (T, 1H, BTBT ring), 7.59-7.41 (3H, BTBT ring and phenyl), 7.31-7.28 (3H, phenyl), 7.36 (d, 1H, BTBT ring), _{2.77 (t, 2H, ArCH 2} ), 1.70 (q, 2H, ArCH 2 CH 2), 1.2~1.4 (m, 14H, -CH 2 -), 0.88 (t, 3H, _CH 3)
About the obtained compound A-1, the solubility at 25 degreeC with respect to various solvents, preparation of the ink for organic-semiconductor materials, preparation of an organic transistor, and the measurement of the transistor characteristic were performed with the following method.

<Preparation of ink 1 for organic semiconductor material>
The compound obtained above was dissolved in xylene at a concentration of 0.5 wt% to obtain an ink for an organic semiconductor material.

<Production of organic thin film transistor>
A silicon wafer with a thermal oxide film (heavy doped p-type silicon (P + -Si), thermal oxide film (SiO2) thickness: 300 nm) is cut to 20 × 25 mm, and then this cut silicon wafer (hereinafter abbreviated as substrate) is Cleaning detergent, ultrapure water, isopropyl alcohol (IPA), acetone, and IPA in this order were subjected to ultrasonic cleaning. Next, the organic semiconductor material inks of Examples 1 to 4 created above were applied onto the substrate, and the substrate was rotated (about 3000 rpm, 30 seconds) to form an organic semiconductor layer.
Further, a source / drain electrode is formed on a substrate coated with an organic semiconductor layer by pattern deposition of gold through a metal mask using a vacuum deposition method (2 × 10 ⁻⁶ Torr). Produced. (Channel length: channel width = 75 μm: 3000 μm).

[Evaluation]
(1) Evaluation of Solubility 2% by mass of the obtained compound was dissolved at 40 ° C., and the solution appearance when allowed to stand at room temperature for 1 hour was visually observed.
◯: Completely dissolved without precipitates x: Precipitates present (2) Evaluation of storage stability of organic semiconductor ink The organic semiconductor ink was stored at room temperature for 1 week, and the presence or absence of precipitates in the ink was observed.
○: No precipitate ×: Precipitate (3) Evaluation of organic thin film transistor characteristics The above organic thin film transistor is evaluated between a source electrode and a drain electrode using a source / measurement unit of two power sources in a normal air atmosphere. The flowing current was measured by measuring (transfer characteristics) the voltage applied to the gate electrode (P + -Si) while sweeping the voltage (Vsg: +40 to -60V) (source electrode-drain electrode voltage Vsd: -80V). The mobility was calculated from the slope of √Id−Vg in the transfer characteristic by a known method using a saturation characteristic equation. The on / off ratio was calculated on the basis of each current that flowed, with the gate voltage set to -100V on and 0V off.

Example 2 Synthesis of Compound B-14

  To 253 mg (0.5 mmol) of 2-decyl-9-iodoBTBT obtained by the synthesis method described in Example 1, 1.0 g (4.6 mmol) of potassium phosphate, 0.5 g (4.1 mmol) of phenylboronic acid, dimethyl 58 mL of sulfoxide was added, and nitrogen gas was bubbled at 25 ° C. for 15 minutes. Under a nitrogen atmosphere, 0.3 g of tetrakis (triphenylphosphine) palladium was added, the temperature was raised to 80 degrees, and the mixture was heated and stirred for 5 hours. After the reaction solution was cooled to room temperature, it was added to 375 mL of water to prepare a suspension, and further 100 mL of chloroform was added to this suspension to prepare a mixed solution. After the mixture was transferred to a separatory funnel, the chloroform layer was washed 3 times with 100 mL of water. 3 g of magnesium sulfate was added to the chloroform layer, stirred at room temperature for 1 hour, dried, and then concentrated to obtain a solid. The solid was dissolved in 500 mL of cyclohexane heated to 50 ° C., and 2 g of silica gel and 2 g of a metal scavenger were added to the solution to prepare a slurry. After stirring the slurry at 50 ° C. for 1 hour, the silica gel and the metal scavenger were removed by filtration and recrystallized from the filtrate to give 148 mg (yield of white crystals of 2-decyl-9-phenylBTBT as compound B-14. Rate, 65%).

The obtained compound B-14 was subjected to structural analysis by 1H-NMR.
1H-NMR (300 MHz, CDCl3): δ 8.02 (d, 1H, BTBT ring), 7.91 (d, 1H, BTBT ring), 7.53 (d, 1H, BTBT ring), 7.45 ( t, 1H, BTBT ring), 7.69-7.59 (7H, BTBT ring and phenyl), 7.45-7.38 (3H, phenyl), 7.29 (d, 1H, BTBT ring), 2 _{.77 (t, 2H, ArCH 2} ), 1.70 (q, 2H, ArCH 2 CH 2), 1.2~1.4 (m, 14H, -CH 2 -), 0.88 (t, 3H , CH ₃ )

  About the obtained compound B-14, the solubility in 25 degreeC with respect to various solvents, preparation of the ink for organic-semiconductor materials, preparation of an organic transistor, and the measurement of transistor characteristics were performed like Example 1. FIG.

Example 3 Synthesis of Compound B-8

4.96 g (13 mmol) of 2-decyl-BTBT obtained by the method described in Example 1 was dissolved in 320 mL of dichloromethane and then cooled to −50 ° C., and 24 mL of a 1.2 M dichloromethane solution of fuming nitric acid was added dropwise over 30 minutes. . After further stirring at −50 ° C. for 2 hours, 26 mL of saturated aqueous sodium hydrogen carbonate solution was added to stop the reaction. The lower layer was separated by separation, washed with 10% brine, dried over anhydrous magnesium sulfate and concentrated to dryness to obtain a crude solid. This solid was recrystallized from 2-butanone to obtain yellow crystals of 2-decyl-7-nitroBTBT, 3.72 g (yield, 67%).

Next, 2.56 g (6 mmol) of 2-decyl-7-nitroBTBT and 1.86 g of tin powder were suspended in 90 mL of acetic acid, and 20.3 g of concentrated hydrochloric acid was slowly added dropwise with heating and stirring at about 70 ° C. Furthermore, after reacting at 100 ° C. for 1 hour, the mixture was cooled to 10 ° C. or lower and the solid was collected by filtration. This solid was dispersed in about 100 mL of chloroform, washed sequentially with concentrated aqueous ammonia and saturated brine, dried over anhydrous magnesium sulfate, and concentrated to dryness to obtain a crude solid. This solid was separated and purified on a silica gel column (chloroform / cyclohexane = 1/1, 1% triethylamine added) and recrystallized from petroleum benzine to give a pale red 2-decyl-6-chloro-7-aminoBTBT 1.13 g (Yield, 44%) was obtained.

Further, 60 mL of dichloromethane was added to 2-decyl-6-chloro-7-aminoBTBT (4 mmol), and 864 mg of trifluoroborate ether complex and 504 mg of t-butyl nitrite were added dropwise under cooling at −15 ° C. After raising the reaction temperature to 25 ° C. in about 1 hour, the mixture was reacted for 3 hours under heating and reflux, then diluted with chloroform, washed with 10% brine, dried over anhydrous sodium sulfate, and concentrated to dryness. The obtained crude solid was purified with a silica gel column (chloroform / cyclohexane = 1/1) and recrystallized from cyclohexane to obtain 2.27 g of 2-decyl-6-chloroBTBT (yield, 91%).

Finally, 2-decyl-6-chloroBTBT 300 mg (0.5 mmol), dioxane 8 mL, potassium carbonate 198 mg, 4- (phenylethynyl) phenylboric acid pinacol ester 115 mg, [1,3-bis (2,6-diisopropylphenyl) After adding 33 mg of imidazol-2-ylidene] (3-chloropyridyl) palladium (II) dichloride and bubbling argon gas for 20 minutes, the mixture was heated and stirred at 80 ° C. for 22 hours. The reaction solution was diluted with chloroform, washed with 10% brine, and the lower layer was concentrated to dryness to obtain a crude solid. The solid was dissolved in 500 mL of cyclohexane heated to 50 ° C., and 2 g of silica gel and 2 g of a metal scavenger were added to the solution to prepare a slurry. After stirring the slurry at 50 ° C. for 1 hour, the silica gel and the metal scavenger were removed by filtration and recrystallized from the filtrate to give 147 mg of 2-decyl-6-ethynylbenzene BTBT as a compound B-8 (yield, 64%). )

The obtained compound B-8 was subjected to structural analysis by 1H-NMR.
1H-NMR (300 MHz, CDCl ₃ ): δ 8.02 (d, 1H, BTBT ring), 7.98 (d, 1H, BTBT ring), 7.53 (d, 1H, BTBT ring), 7.48 (T, 1H, BTBT ring), 7.59-7.41 (3H, BTBT ring and phenyl), 7.31-7.28 (3H, phenyl), 7.36 (d, 1H, BTBT ring), _{2.77 (t, 2H, ArCH 2} ), 1.70 (q, 2H, ArCH 2 CH 2), 1.2~1.4 (m, 14H, -CH 2 -), 0.88 (t, 3H, _CH 3)

  With respect to the obtained compound B-8, solubility in various solvents at 25 ° C., preparation of an ink for organic semiconductor materials, preparation of an organic transistor, and measurement of transistor characteristics were carried out in the same manner as in Example 1.

Example 4 Synthesis of Compound B-1

To 253 mg (0.5 mmol) of 2-decyl-6-chloroBTBT obtained by the synthesis method described in Example 3, 8 mL of dioxane, 198 mg of potassium carbonate, 70 mg of 4-phenylboric acid, [1,3-bis (2,6-diisopropyl) Phenyl) imidazol-2-ylidene] (3-chloropyridyl) palladium (II) dichloride (33 mg) was added, argon gas was bubbled for 20 minutes, and the mixture was heated with stirring at 80 ° C. for 22 hours. The reaction solution was diluted with chloroform, washed with 10% brine, and the lower layer was concentrated to dryness to obtain a crude solid. The solid was dissolved in 500 mL of cyclohexane heated to 50 ° C., and 2 g of silica gel and 2 g of a metal scavenger were added to the solution to prepare a slurry. After stirring the slurry at 50 ° C. for 1 hour, the silica gel and the metal scavenger were removed by filtration and recrystallized from the filtrate to give 180 mg of 2-decyl-6-phenylBTBT as compound B-21 (yield, 78%). Got.

The obtained compound A-4 was subjected to structural analysis by 1H-NMR.
1H-NMR (300 MHz, CDCl3): δ 8.20 (d, 1H, BTBT ring), 8.02 (d, 1H, BTBT ring), 7.91 (d, 1H, BTBT ring), 7.45 ( t, 1H, BTBT ring), 7.69-7.59 (7H, BTBT ring and phenyl), 7.45-7.38 (3H, phenyl), 7.29 (d, 1H, BTBT ring), 2 _{.77 (t, 2H, ArCH 2} ), 1.70 (q, 2H, ArCH 2 CH 2), 1.2~1.4 (m, 14H, -CH 2 -), 0.88 (t, 3H , CH ₃ )

  About the obtained compound B-21, the solubility at 25 degreeC with respect to various solvents, preparation of the ink for organic-semiconductor materials, preparation of an organic transistor, and the measurement of transistor characteristics were performed like Example 1. FIG.

[Comparative Example 1] Synthesis of Comparative Example 1

BTBT (12.3 g, 51.2 mmol) was dissolved in 700 mL of dichloromethane and then cooled to 0 ° C., and 100 mL of a 1.2 M dichloromethane solution of fuming nitric acid was added dropwise over 60 minutes. After further stirring at 0 ° C. for 6 hours, 4.4 mL of concentrated sulfuric acid was added, and the mixture was further stirred for 2 hours. The reaction was stopped by adding 150 mL of saturated aqueous sodium hydrogen carbonate solution. The lower layer was separated by separation, washed with 10% brine, dried over anhydrous magnesium sulfate and concentrated to dryness to obtain a crude solid. This solid was recrystallized from toluene to obtain 1.7 g of orange crystals of 2,7-dinitroBTBT (yield, 10%).

Thereafter, 1.7 g (5.1 mmol) of 2,7-dinitro BTBT and 1.84 g of tin powder were suspended in 30 mL of acetic acid, and 5.4 mL of concentrated hydrochloric acid was slowly added dropwise with heating and stirring at about 70 ° C. Furthermore, after reacting at 100 ° C. for 1 hour, the mixture was cooled to 10 ° C. or lower and the solid was collected by filtration. This solid was dispersed in about 100 mL of chloroform, washed sequentially with concentrated aqueous ammonia and saturated brine, dried over anhydrous magnesium sulfate, and concentrated to dryness to obtain a crude solid. This solid was recrystallized from petroleum benzine to obtain 1.1 g (yield, 82%) of 2,7-diaminoBTBT.

Then, 60 mL of dichloromethane was added to 1.13 g (4.2 mmol) of 2,7-diaminoBTBT, and 1.62 g of trifluoroborate ether complex and 1.01 g of t-butyl nitrite were added dropwise while cooling at −15 ° C. After raising the reaction temperature to 5 ° C. in about 1 hour, a solution of 3.2 g of iodine, 1.32 g of potassium iodide and 100 mg of tetrabutylammonium iodide in a dichloromethane-THF mixture (1: 2) in 24 mL was added. The mixture was reacted for 8 hours under reflux with heating, diluted with chloroform, washed successively with 10% sodium thiosulfate, 5M sodium hydroxide, and 10% brine, dried over anhydrous sodium sulfate, and concentrated to dryness. The obtained dark brown crude solid was purified by a silica gel column (chloroform / cyclohexane = 1/1) and crystallized from chloroform-methanol. Subsequently, recrystallization from ligroin yielded 889 mg of 2,7-diiodo BTBT (yield, 43%).

Finally, 4.0 g (184 mmol) of potassium phosphate, 4.0 g (32 mmol) of phenylboronic acid and 240 mL of dimethyl sulfoxide were added to 889 mg (1.8 mmol) of 2,7-diiodo BTBT, and nitrogen gas was added at 25 ° C. under 15 ° C. Bubbled for a minute. Under a nitrogen atmosphere, 1.2 g of tetrakis (triphenylphosphine) palladium was added, the temperature was raised to 80 degrees, and the mixture was heated and stirred for 5 hours. After cooling the reaction solution to room temperature, it was added to 1 L of water to prepare a suspension, and further 500 mL of chloroform was added to this suspension to prepare a mixed solution. After the mixture was transferred to a separatory funnel, the chloroform layer was washed with 300 mL of water three times. 10 g of magnesium sulfate was added to the chloroform layer, stirred at room temperature for 1 hour, dried, and then concentrated to obtain a solid. This solid was dissolved in 1 L of cyclohexane heated to 50 degrees, and 10 g of silica gel and 10 g of a metal scavenger were added to this solution to prepare a slurry. After stirring the slurry at 50 ° C. for 1 hour, the silica gel and the metal scavenger were removed by filtration, and recrystallization from the filtrate gave 2,59-diphenyl BTBT white crystals, 459 mg (yield, 65%). .

The obtained compound was subjected to structural analysis by 1H-NMR.
1H-NMR (300 MHz, CDCl ₃ ): δ 8.09 (d, 2H, BTBT ring), 7.91 (d, 2H, BTBT ring), 7.69 (d, 2H, BTBT ring), 7.67 (T, 4H, phenyl), 7.46 (t, 4H, phenyl), 7.35 (t, 2H, phenyl).

About the obtained compound, the solubility at 25 degreeC with respect to various solvents, preparation of the ink for organic-semiconductor materials, preparation of an organic transistor, and the measurement of transistor characteristics were performed like Example 1. FIG.

[Comparative Example 2]
Synthesis of Comparative Example 2

2.56 g (6.0 mmol) of 2-decyl-7-nitroBTBT obtained by the method described in Example 3 and 0.9 g of tin powder were suspended in 90 mL of acetic acid, and heated at about 70 ° C. with stirring and concentrated hydrochloric acid 10 .1 g was slowly added dropwise. Furthermore, after reacting at 100 ° C. for 1 hour, the mixture was cooled to 10 ° C. or lower and the solid was collected by filtration. This solid was dispersed in about 100 mL of chloroform, washed sequentially with concentrated aqueous ammonia and saturated brine, dried over anhydrous magnesium sulfate, and concentrated to dryness to obtain a crude solid. This solid was separated and purified on a silica gel column (chloroform / cyclohexane = 1/1, 1% triethylamine added) and recrystallized from petroleum benzine to give 1.76 g of a slightly red 2-decyl-7-aminoBTBT (yield, 74%).

Then, 60 mL of dichloromethane was added to 1.76 g (4.45 mmol) of 2-decyl-7-aminoBTBT, and 864 mg of trifluoroborate / ether complex and 504 mg of t-butyl nitrite were added dropwise under cooling at −15 ° C. After raising the reaction temperature to 5 ° C. in about 1 hour, a solution of 1.6 g of iodine, 1.32 g of potassium iodide and 100 mg of tetrabutylammonium iodide in a dichloromethane-THF mixture (1: 2) 12 mL was added. The mixture was reacted for 8 hours under reflux with heating, diluted with chloroform, washed successively with 10% sodium thiosulfate, 5M sodium hydroxide, and 10% brine, dried over anhydrous sodium sulfate, and concentrated to dryness. The obtained dark brown crude solid was purified by a silica gel column (chloroform / cyclohexane = 1/1) and crystallized from chloroform-methanol. Next, recrystallization from ligroin yielded 969 mg of 2-decyl-7-iodoBTBT (yield, 43%).

To 969 mg (1.9 mmol) of 2-decyl-7-iodoBTBT, 4.0 g (18.2 mmol) of potassium phosphate, 2.0 g (16.4 mmol) of phenylboronic acid and 240 mL of dimethyl sulfoxide were added, and nitrogen was added at 25 ° C. Gas was bubbled for 15 minutes. Under a nitrogen atmosphere, 1.2 g of tetrakis (triphenylphosphine) palladium was added, the temperature was raised to 80 degrees, and the mixture was heated and stirred for 5 hours. After cooling the reaction solution to room temperature, it was added to 600 mL of water to prepare a suspension, and further 300 mL of chloroform was added to this suspension to prepare a mixed solution. After the mixture was transferred to a separatory funnel, the chloroform layer was washed with 300 mL of water three times. 10 g of magnesium sulfate was added to the chloroform layer, stirred at room temperature for 1 hour, dried, and then concentrated to obtain a solid. This solid was dissolved in 1000 mL of cyclohexane heated to 50 degrees, and 10 g of silica gel and 10 g of a metal scavenger were added to this solution to prepare a slurry. After stirring the slurry at 50 ° C. for 1 hour, the silica gel and the metal scavenger were removed by filtration and recrystallized from the filtrate to obtain 567 mg (yield, 65%) of white crystals of 2-decyl-7-phenylBTBT. Obtained.

The obtained compound was subjected to structural analysis by 1H-NMR.
1H-NMR (300 MHz, CDCl ₃ ): δ 8.12 (d, 1H, BTBT ring), 7.92 (d, 1H, BTBT ring), 7.79 (d, 1H, BTBT ring), 7.73 (S, 1H, BTBT ring), 7.69 (d x 2, 3H, BTBT ring and phenyl), 7.49 (t, 2H, phenyl), 7.38 (tt, 1H, BTBT ring), 7. 29 (dd, 1H, BTBT _{ring), 2.77 (t, 2H,} ArCH 2), 1.70 (q, 2H, ArCH 2 CH 2), 1.2~1.4 (m, 14H, -CH _2- ), 0.88 (t, 3H, CH ₃ )

  About the obtained compound, the solubility at 25 degreeC with respect to various solvents, preparation of the ink for organic-semiconductor materials, preparation of an organic transistor, and the measurement of transistor characteristics were performed like Example 1. FIG.

From Table 1 above, the organic semiconductor material of the present invention exhibits practical TFT performance in addition to excellent solvent solubility and ink storage stability. On the other hand, the material of the comparative example shows practical TFT characteristics, but has low solvent solubility and low ink storage stability.

  The compound of the present invention can be used as an organic semiconductor, and can be used for an organic thin film transistor using the organic semiconductor material as an organic semiconductor layer.

1. Substrate 2. 2. Gate electrode 3. Gate insulating film 4. Organic semiconductor Source electrode 6. Drain electrode

Claims (8)

Compound A represented by either the following formula (1) or (2).

... (1)

... (2)
(In the above formulas (1) and (2), X represents an S atom,
R ₁ , R ₂ , and R ₃ each independently represent a halogen atom, a phenylethynyl group that may have a substituent, a naphthylethynyl group, a thienylethynyl group that may have a substituent, an oxazolylethynyl group, Alternatively, it represents one of the structures represented by the following formula (4).

... (4)
(In the above formula (4), Y represents either an S atom or an O atom,
R ₄ represents an alkylene group having 1 to 20 carbon atoms or an aromatic group,
R ₅ represents an alkyl group having 1 to 20 carbon atoms,
n represents 0 or 1. However, when n is 0, R ₄ is terminally substituted with a hydrogen atom. ) A composition comprising the compound A according to claim 1. The organic-semiconductor material containing the compound A of Claim 1. An organic semiconductor ink containing the compound A according to claim 1. A film containing the compound A according to claim 1. An organic semiconductor film containing the compound A according to claim 1. The organic thin-film transistor which has a semiconductor layer containing the compound A of Claim 1. The organic-semiconductor device containing the compound A of Claim 1.

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