JP2005154371A - New benzodichalcogenophene derivative, method for producing the same and organic semiconductor device produced by using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new benzodichalcogenophene derivative satisfying both of the high field-effect mobility (≥0.1 cm<SP>2</SP>/Vs) and high on/off current ratio (≥10<SP>5</SP>) required in organic semiconductor materials, a method for the production of the derivative as an easily purifiable practical material, and an organic semiconductor device produced by using the derivative. <P>SOLUTION: The benzodichalcogenophene derivative is expressed by general formula (1) or general formula (2) (X<SP>1</SP>to X<SP>4</SP>are each independently selenium atom or tellurium atom). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a novel benzodichalcogenophene derivative, a method for producing the same, and an organic semiconductor device using the same, and more particularly, a novel useful as an organic electronic component material used for electrical, electronic, and photoelectric components. The present invention relates to a novel benzodichalcogenophene derivative, a production method thereof, and an organic semiconductor device using the same. Such a novel condensed heterocyclic compound is an organic electronic component material that can be used for a thin film transistor (TFT) having an organic semiconductor layer, a light emitting device having an organic carrier transporting layer, or a light emitting layer.

  A thin film transistor having an organic semiconductor layer is attracting attention as a low-cost device and a lightweight device as an inexpensive alternative to the current silicon-based TFT. In such a thin film transistor, it becomes possible to manufacture a device without using a high-cost process required in manufacturing a silicon device by using an organic material. In addition, by utilizing the advantages unique to organic materials such as lightweight and flexible, application to smart tags, lightweight displays, etc. that have never been seen before has been devised.

  On the other hand, the organic semiconductor device generally has a drawback that the response speed is slow. This is due to the low mobility of conductive carriers in the organic thin film active layer. In order to overcome this problem, various organic semiconductor materials have been proposed to date and their mobility has been studied.

For example, in pentacene, which is a polycyclic aromatic molecule in which five benzene rings are linearly condensed, a high mobility (0.1 to 1.0 cm ² / Vs) comparable to amorphous silicon has been reported. The performance of a pentacene-based TFT largely depends on the purity of the active layer, pentacene, and the above performance is achieved for the first time by performing multiple vacuum sublimation purifications and sublimation purifications in a hydrogen stream before device fabrication. (Non-Patent Document 1).

Non-Patent Document 2 reports that a mobility of 0.04 cm ² / Vs was obtained in a benzodithiophene dimer obtained by dimerizing a benzodithiophene monomer.

Furthermore, in recent years, a material having mobility of 0.14 cm ² / Vs by combining thiophene and fluorene has been reported (see Non-Patent Document 3). Furthermore, recently, mobility of the order of 0.1 cm ² / Vs in anthracene dimers and trimers has been reported (Non-patent Document 4).

  The materials described in Non-Patent Documents 2 to 4 require a multi-stage reaction in the production and also include a low-yield stage. There are still problems to overcome in the manufacturing process. Further, pentacene described in Non-Patent Document 1 has a problem in purification of the material.

で表される二価の置換基であって、Ｙ¹〜Ｙ⁷はそれぞれ同一かまたは異なり、硫黄原子、酸素原子または窒化物ＮＲ^a（Ｒ^aは水素原子、塩素原子、炭素数１〜８のアルキル基または置換されてもよいアリール基）である）で示される有機分子配向薄膜用材料に関する提案がなされている。 As materials for overcoming these conventional problems, Patent Document 1 discloses the following general formula (5),
R—X ¹ —CH═CH—X ² —R (5)
(Wherein X ¹ and X ² are each independently the following formulas:

In which Y ¹ to Y ⁷ are the same or different and each represents a sulfur atom, an oxygen atom or a nitride NR ^a (R ^a is a hydrogen atom, a chlorine atom, a carbon number of 1 to 8). In which an organic molecular alignment thin film material is represented by the following formula:

（式中、Ｘは酸素原子、アミン、又は硫黄原子である）で示される有機半導体化合物に関する提案がなされている。 Similarly, for the purpose of overcoming the problems of the prior art, Patent Document 2 includes the following general formulas (6) and (7),

The proposal regarding the organic-semiconductor compound shown by (In formula, X is an oxygen atom, an amine, or a sulfur atom) is made | formed.

Japanese Patent Laid-Open No. 2000-122068 JP-A-11-195790 IEEE Electron Dev. Lett. 1997, 18, 87 Joyce G. Laquindanum et al, Adv. Mater. 1997, 9, 36 Z.Bao et al, J.Am.CHEM.Soc.2001,123,9214 Suzuki et al, Angew.Chem.Int.Ed.2003,42,1159

  The thin film formation method described in Patent Document 1 aims to enable inexpensive production by producing a highly oriented organic molecular alignment thin film by a normal vacuum evaporation method, not by an organic molecular beam evaporation method. However, there is no mention of specific field effect mobility, on / off current ratio, and the like as a manufactured thin film device.

Further, the material described in Patent Document 2 has high field effect mobility (0.01 cm ² / Vs or more) and heat resistance (melting point is 250 ° C. or more), and the on / off current in a state incorporated in the device. Although a ratio of 10 ² has been reported, none of the characteristics are sufficient as the characteristics of the organic semiconductor material.

Accordingly, an object of the present invention is to provide a novel benzoate that satisfies both the high field effect mobility (0.1 cm ² / Vs or more) required for organic semiconductor materials and the high on / off current ratio (10 ⁵ or more). It is to provide a dichalcogenophene derivative.

  Another object of the present invention is to provide a production method of such a benzodichalcogenophene derivative that can be easily produced and purified as a practical material.

  Furthermore, another object of the present invention is to provide an organic semiconductor device having excellent electrical, electronic and photoelectric properties by using a novel benzodichalcogenophene derivative as an organic semiconductor material.

  As a result of intensive research on organic semiconductor materials to solve the above problems, the present inventors have found that a novel benzodichalcogenophene derivative having a specific structure containing a selenium atom or a tellurium atom as a chalcogen atom is used as an organic semiconductor material. In order to complete the present invention, it has been found that it has excellent electrical, electronic and photoelectric properties, and has also found a method capable of producing the novel benzodichalcogenophene derivative easily and inexpensively. It came.

（式中、Ｘ¹およびＸ²はそれぞれ独立にセレン原子またはテルル原子、ｎは１〜３の整数、Ｒ¹およびＲ²はそれぞれ独立に水素原子、ハロゲン原子、炭素数２〜１８のアルキル基、又はカルコゲン原子を有していてもよいアリール基であり、該アリール基は、ハロゲン原子、炭素数２〜１８のアルキル基、炭素数２〜１８のアルキルオキシ基、炭素数２〜１８のアルキルチオ基およびアリール基からなる群から選択される少なくとも１種の置換基を有していてもよい）で表されることを特徴とするものである。 That is, the benzodichalcogenophene derivative of the present invention has the following general formula (1),

Wherein X ¹ and X ² are each independently a selenium atom or tellurium atom, n is an integer of 1 to 3, R ¹ and R ² are each independently a hydrogen atom, a halogen atom, or an alkyl group having 2 to 18 carbon atoms. Or an aryl group optionally having a chalcogen atom, and the aryl group includes a halogen atom, an alkyl group having 2 to 18 carbon atoms, an alkyloxy group having 2 to 18 carbon atoms, and an alkylthio group having 2 to 18 carbon atoms. It may have at least one kind of substituent selected from the group consisting of a group and an aryl group).

（式中、Ｘ³およびＸ⁴はそれぞれ独立にセレン原子またはテルル原子、ｎは１〜３の整数、Ｒ³およびＲ⁴はそれぞれ独立に水素原子、ハロゲン原子、炭素数２〜１８のアルキル基、又はカルコゲン原子を有していてもよいアリール基であり、該アリール基は、ハロゲン原子、炭素数２〜１８のアルキル基、炭素数２〜１８のアルキルオキシ基、炭素数２〜１８のアルキルチオ基およびアリール基からなる群から選択される少なくとも１種の置換基を有していてもよい）で表されることを特徴とするものである。 Another benzodichalcogenophene derivative of the present invention has the following general formula (2),

Wherein X ³ and X ⁴ are each independently a selenium atom or tellurium atom, n is an integer of 1 to ³ , R ³ and R ⁴ are each independently a hydrogen atom, a halogen atom, or an alkyl group having 2 to 18 carbon atoms. Or an aryl group optionally having a chalcogen atom, and the aryl group includes a halogen atom, an alkyl group having 2 to 18 carbon atoms, an alkyloxy group having 2 to 18 carbon atoms, and an alkylthio group having 2 to 18 carbon atoms. It may have at least one kind of substituent selected from the group consisting of a group and an aryl group).

または、次の一般式（４）、

（式中、Ｘ⁵およびＸ⁶はそれぞれ独立にカルコゲン原子、ｎは１〜３の整数、Ｒ⁵およびＲ⁶はそれぞれ独立に水素原子、ハロゲン原子、炭素数２〜１８のアルキル基、又はカルコゲン原子を有していてもよいアリール基であり、該アリール基は、ハロゲン原子、炭素数２〜１８のアルキル基、炭素数２〜１８のアルキルオキシ基、炭素数２〜１８のアルキルチオ基およびアリール基からなる群から選択される少なくとも１種の置換基を有していてもよい）で表される縮合多環芳香族化合を製造するにあたり、
末端にＲ⁵およびＲ⁶（但し、Ｒ⁵およびＲ⁶が水素原子の場合には該水素原子に対する保護基）を別々に有する不飽和炭素結合を含む２個の置換基と、Ｘ⁵およびＸ⁶を別々に含む２個の置換基とを同一環上に有するベンゼン環において、Ｒ⁵（但し、Ｒ⁵が水素原子の場合には該水素原子に対する保護基）を有する不飽和炭素結合を含む置換基とＸ⁵を含む置換基との間と、Ｒ⁶（但し、Ｒ⁶が水素原子の場合には該水素原子に対する保護基）を有する不飽和炭素結合を含む置換基とＸ⁶を含む置換基との間とで、夫々縮合反応させる工程を含むことを特徴とするベンゾジカルコゲノフェン誘導体の製造方法である。 Further, the present invention provides the following general formula (3),

Or the following general formula (4),

Wherein X ⁵ and X ⁶ are each independently a chalcogen atom, n is an integer of 1 to 3, R ⁵ and R ⁶ are each independently a hydrogen atom, a halogen atom, an alkyl group having 2 to 18 carbon atoms, or a chalcogen An aryl group which may have an atom, and the aryl group includes a halogen atom, an alkyl group having 2 to 18 carbon atoms, an alkyloxy group having 2 to 18 carbon atoms, an alkylthio group having 2 to 18 carbon atoms and an aryl group. In the production of the condensed polycyclic aromatic compound represented by (which may have at least one substituent selected from the group consisting of groups),
Two substituents containing an unsaturated carbon bond separately having R ⁵ and R ^{6 at the} ends (provided that when R ⁵ and R ⁶ are hydrogen atoms, a protecting group for the hydrogen atom), X ⁵ and X 6 A benzene ring having two substituents containing ⁶ separately on the same ring, including an unsaturated carbon bond having R ⁵ (provided that when R ⁵ is a hydrogen atom, a protecting group for the hydrogen atom) A substituent containing an unsaturated carbon bond having a substituent and a substituent containing X ⁵ , and R ⁶ (provided that when R ⁶ is a hydrogen atom, a protecting group for the hydrogen atom), and X ⁶ A method for producing a benzodichalcogenophene derivative, comprising a step of condensation reaction with a substituent.

  Furthermore, the present invention is an organic semiconductor device characterized in that at least one compound represented by the general formula (1) and / or (2) is used as an organic semiconductor material.

  As described in Patent Documents 1 and 2 above, high mobility has been reported in a field effect thin film transistor using a benzodichalcogenophene derivative containing a sulfur atom. This is thought to be due to the fact that effective movement of the carrier species in the thin film is enabled by strong intermolecular interactions via sulfur atoms. Based on this knowledge, the present inventors used a benzodichalcogenophene derivative having a selenium atom or tellurium atom located in a high cycle in the group 16 element of the same group as sulfur as an organic semiconductor material. Surprisingly, it has been found that the intermolecular interaction in the thin film is further increased and the field effect mobility is further improved as compared with the case of sulfur atoms, and the novel benzodichalcogenophene derivative of the present invention and The organic semiconductor device used was completed.

  By the way, in the synthesis of a benzodichalcogenophene derivative containing a sulfur atom in the prior art, a multi-step production process using an expensive raw material is required, so that such a compound has a problem as a practical material. Furthermore, it has been extremely difficult to introduce a plurality of selenium atoms or tellurium atoms into a condensed polycyclic aromatic skeleton based on the knowledge of organic synthetic chemistry so far. As a result of studying a simple method for synthesizing a benzodichalcogenophene derivative containing a selenium atom or a tellurium atom, the present inventors have used a commercially available compound at a low price, for example, dibromobenzene as a raw material. A simple method capable of producing the target compound was found by the step reaction, and the production method of the present invention was completed. The method of the present invention is that a cheap raw material can be used, there are few production steps, each step can be produced with high efficiency, and furthermore, it is a production method with less contamination of impurities, and is extremely easy to purify. , Etc. It has excellent features that have never been seen before.

In the novel benzodichalcogenophene derivative of the present invention, high field effect mobility (0.1 cm ² / Vs or more) required for organic semiconductor materials and high on / off current ratio (10 ⁵ or more) are obtained. Can be achieved. Moreover, in the manufacturing method of this invention, the said benzodichalcogenophene derivative can be manufactured simply and cheaply. Therefore, according to the present invention, an organic semiconductor device having excellent electrical, electronic, and photoelectric characteristics can be manufactured at a lower cost and more easily than ever.

（式中、Ｘ¹およびＸ²はそれぞれ独立にセレン原子またはテルル原子、ｎは１〜３の整数、Ｒ¹およびＲ²はそれぞれ独立に水素原子、ハロゲン原子、炭素数２〜１８のアルキル基、又はカルコゲン原子を有していてもよいアリール基であり、該アリール基は、ハロゲン原子、炭素数２〜１８のアルキル基、炭素数２〜１８のアルキルオキシ基、炭素数２〜１８のアルキルチオ基およびアリール基からなる群から選択される少なくとも１種の置換基を有していてもよい）で表されるものか、あるいは次の一般式（２）、

（式中、Ｘ³およびＸ⁴はそれぞれ独立にセレン原子またはテルル原子、ｎは１〜３の整数、Ｒ³およびＲ⁴はそれぞれ独立に水素原子、ハロゲン原子、炭素数２〜１８のアルキル基、又はカルコゲン原子を有していてもよいアリール基であり、該アリール基は、ハロゲン原子、炭素数２〜１８のアルキル基、炭素数２〜１８のアルキルオキシ基、炭素数２〜１８のアルキルチオ基およびアリール基からなる群から選択される少なくとも１種の置換基を有していてもよい）で表されるものである。 The benzodichalcogenophene derivative of the present invention has the following general formula (1),

Wherein X ¹ and X ² are each independently a selenium atom or tellurium atom, n is an integer of 1 to 3, R ¹ and R ² are each independently a hydrogen atom, a halogen atom, or an alkyl group having 2 to 18 carbon atoms. Or an aryl group optionally having a chalcogen atom, and the aryl group includes a halogen atom, an alkyl group having 2 to 18 carbon atoms, an alkyloxy group having 2 to 18 carbon atoms, and an alkylthio group having 2 to 18 carbon atoms. Which may have at least one substituent selected from the group consisting of a group and an aryl group), or the following general formula (2),

Wherein X ³ and X ⁴ are each independently a selenium atom or tellurium atom, n is an integer of 1 to ³ , R ³ and R ⁴ are each independently a hydrogen atom, a halogen atom, or an alkyl group having 2 to 18 carbon atoms. Or an aryl group optionally having a chalcogen atom, and the aryl group includes a halogen atom, an alkyl group having 2 to 18 carbon atoms, an alkyloxy group having 2 to 18 carbon atoms, and an alkylthio group having 2 to 18 carbon atoms. And may have at least one substituent selected from the group consisting of a group and an aryl group.

X ¹ and X ² and X ³ and X ⁴ in the above formula are selenium atoms or tellurium atoms, and by selecting these atoms among the chalcogen atoms, they are more excellent in electrical and electronic properties than sulfur atoms. And optoelectric properties are obtained.

In addition, among R ¹ and R ² and R ³ and R ^{4 in} the above formula, preferred examples of the aryl group include a phenyl group, a naphthyl group, an anthranyl group, a furyl group, a thienyl group, a selenofuryl group, and a thienothienyl group. be able to.

または、次の一般式（４）、

（式中、Ｘ⁵およびＸ⁶はそれぞれ独立にカルコゲン原子、ｎは１〜３の整数、Ｒ⁵およびＲ⁶はそれぞれ独立に水素原子、ハロゲン原子、炭素数２〜１８のアルキル基、又はカルコゲン原子を有していてもよいアリール基であり、該アリール基は、ハロゲン原子、炭素数２〜１８のアルキル基、炭素数２〜１８のアルキルオキシ基、炭素数２〜１８のアルキルチオ基およびアリール基からなる群から選択される少なくとも１種の置換基を有していてもよい）で表されるベンゾジカルコゲノフェン誘導体を製造するものであり、Ｘ⁵およびＸ⁶はセレン原子またはテルル原子に限定されず、これら以外のカルコゲン原子を含むものである。 Next, the production method of the present invention has the following general formula (3),

Or the following general formula (4),

Wherein X ⁵ and X ⁶ are each independently a chalcogen atom, n is an integer of 1 to 3, R ⁵ and R ⁶ are each independently a hydrogen atom, a halogen atom, an alkyl group having 2 to 18 carbon atoms, or a chalcogen An aryl group which may have an atom, and the aryl group includes a halogen atom, an alkyl group having 2 to 18 carbon atoms, an alkyloxy group having 2 to 18 carbon atoms, an alkylthio group having 2 to 18 carbon atoms and an aryl group. X ⁵ and X ⁶ are selenium atoms or tellurium atoms, which may have at least one substituent selected from the group consisting of groups) It is not limited to this, It includes a chalcogen atom other than these.

In the production method of the present invention, two substituents containing an unsaturated carbon bond having R ⁵ and R ^{6 at} the ends (provided that when R ⁵ and R ⁶ are a hydrogen atom, separately, a protecting group for the hydrogen atom) A benzene ring having the same group and two substituents separately containing X ⁵ and X ⁶ on the same ring, R ⁵ (provided that when R ⁵ is a hydrogen atom, a protecting group for the hydrogen atom) includes between substituent includes a substituent group and X ⁵ which includes an unsaturated carbon bond, R ⁶ (where, R ⁶ is a protecting group for the hydrogen atom in the case of hydrogen atoms) an unsaturated carbon bond with having By including a step of condensation reaction between the substituent and the substituent containing X ⁶ , the benzodichalcogenophene derivative represented by the general formula (3) or (4) can be obtained easily and inexpensively. Can be manufactured. The substituent containing an unsaturated carbon bond having R ⁵ or R ⁶ at the terminal is preferably an ethynyl group having R ⁵ or R ⁶ at the terminal. Moreover, when R < ⁵ > and R < ⁶ > are hydrogen atoms, a silicon substituent can be used suitably as a protective group with respect to this hydrogen atom, Especially preferably, a trimethylsilyl group (TMS) can be used.

For example, conventionally, a known benzodichalcogenophene derivative in which X ⁵ and X ⁶ in the general formula (3) are both sulfur atoms, R ⁵ and R ⁶ are both hydrogen atoms, and n is 1 is produced. In this case, an expensive thiophene derivative must be used as a starting material, and the number of reaction steps and yield are larger than those of the method of the present invention. Although there was a problem that a considerable amount of product was produced, the production method of the present invention can greatly reduce such a problem.

で表されるように、安価に市販されているジブロモベンゼンを原料として、３〜５段階の反応により前記一般式（３）で表されるベンゾジカルコゲノフェン誘導体を製造することができる。 That is, in the present invention, the following reaction formula is given as an example:

As shown in the formula, a benzodichalcogenophene derivative represented by the general formula (3) can be produced by a reaction of 3 to 5 steps using dibromobenzene commercially available at a low price.

Similarly, among the benzodichalcogenophene derivatives represented by the general formula (4), X ⁵ and X ⁶ are both selenium atoms or sulfur atoms, R ⁵ and R ⁶ are both phenyl groups, and n is 1 The benzodichalcogenophene derivative can be produced according to the following reaction formula.

  In the production method of the present invention, in order to obtain the benzodichalcogenophene derivative of the present invention represented by the general formula (1) or (2), the chalcogen atom may be a selenium atom or a tellurium atom.

  In addition, in order to obtain a compound in which n in the general formula (3) or (4) is represented by 2 or 3, first, a compound in which n is represented by 1 is produced, and then the obtained compounds are combined with each other. What is necessary is just to combine. For this bonding, the compound represented by the general formula (3) or (4) where n is 1 is activated by treatment with an organometallic reagent, and then an oxidative bond formation reaction with a metal salt is preferably used. can do.

The machine semiconductor device of the present invention uses at least one benzodichalcogenophene derivative of the present invention represented by the general formula (1) and / or (2) as an organic semiconductor material. Such an organic semiconductor device is preferably a thin film transistor or a light emitting device, and can achieve a high field effect mobility (0.1 cm ² / Vs or more) and a high on / off current ratio (10 ⁵ or more). It should be noted that known materials and structures can be adopted except that the organic semiconductor material according to the present invention is used, and there is no particular limitation (see FIG. 1).

Hereinafter, the present invention will be specifically described based on examples.
Synthesis example 1
According to the method described in the literature [J. Org. Chem. Vol. 50, P. 3140, (1985)], iodine was added to 1,4-dibromobenzene (manufactured by Tokyo Chemical Industry Co., Ltd.) in concentrated sulfuric acid at 120 ° C. for 6 hours. 1,4-dibromo-2,5-diiodobenzene was prepared (yield 83%). Then, in a nitrogen atmosphere, this was treated with palladium chloride bis (triphenylphosphine), iodide according to the method described in the literature [J. Am. Chem. Soc. Vol. 119, P. 4578, (1997)]. Conversion into 1,4-dibromo-2,5-bis (phenylethynyl) benzene was achieved by reacting with phenylacetylene in diisopropylamine in the presence of cuprous (yield 98%). This reaction proceeded in high yield, much like the literature.

Next, the obtained 1,4-dibromo-2,5-bis (phenylethynyl) benzene (1 g, 2.3 mmol) was lithiated at a low temperature under an inert gas atmosphere to obtain selenium powder (0.36 g, 4. 6 mmol) to give 2,6-diphenyl-benzo [1,2-b: 4,5-b ′] diselenophene (in formula (1), n = 1, X ¹ , X ² = Se, to obtain a R ^1, R ² = phenyl) (1.61 g, 74% yield).
Melting point: 300 ° C. or higher, MS (EI) m / z 436 (M ⁺ , 100%, with an isotope pattern containing two selenium atoms),
Elemental analysis: calculated value (C ₂₂ H ₁₄ Se ₂ ) C, 60.57; H, 3.23%, measured value C, 60.61; H, 3.29%

Synthesis example 2
In the same manner as in Synthesis Example 1, 1,4-dibromo-2,5-diiodobenzene and 4-ethynylbiphenyl (1 g, 5.6 mmol) are reacted to give 1,4-dibromo-2,5-bis. [(4,1′-biphenyl) -1-yl-ethynyl] benzene was obtained. This was treated in the same manner as in Synthesis Example 1, and 2,6-bis [(4,1′-biphenyl) -1-yl] -benzo [1,2-b: 4,5-b ′] diselenophene ( In the general formula (1), n = 1, X ¹ , X ² = Se, R ¹ , R ² = biphenyl) (0.58 g, yield 99%) was obtained.
Melting point: 300 ° C. or higher, MS (MALDI-TOF) m / z 588 (M ⁺ , 100%), elemental analysis: calculated value (C ₃₄ H ₂₂ Se ₂ ) C, 69.40; H, 3.77%, actual measurement Value C, 69.40; H, 3.74%

Synthesis example 3
In Synthesis Example 1, except that tellurium powder was used in place of selenium powder, the reaction between the lithiol of 1,4-dibromo-2,5-bis (phenylethynyl) benzene and tellurium powder was performed in the same manner as in Synthesis Example 1. 2,6-diphenyl-benzo [1,2-b: 4,5-b ′] ditellophene (in the general formula (1), n = 1, X ¹ , X ² = Te, R ¹ , R ² = Phenyl) was obtained with a yield of 40%.
Melting point: 300 ° C. or higher, MS (EI) m / z 534 (M ⁺ , 100%, with an isotope pattern containing two tellurium atoms),
Calcd _{(C 22 H 14 Te 2)} C, 49.52; H, 2.64%, Found C, 49.49; H, 2.65%

Synthesis example 4
1,4-dibromo-2,5-bis (trimethylsilylethynyl) benzene was prepared in the same manner as in Synthesis Example 1 except that trimethylsilylacetylene was used instead of phenylacetylene in Synthesis Example 1, and this was the same as in Synthesis Example 1. To 2,6-bis (trimethylsilyl) -benzo [1,2-b: 4,5-b ′] diselenophene. Further, this was desilylated by alkali treatment, and benzo [1,2-b: 4,5-b ′] diselenophene (in the general formula (1), n = 1, X ¹ , X ² = Se, R ¹ , R ² = H).

Synthesis example 5
The benzo [1,2-b: 4,5-b ′] diselenophene obtained in Synthesis Example 4 is dissolved in tetrahydrofuran (THF), cooled, lithiated with butyllium, and then iron (III) -acetylacetate. Nart was added and stirred. Subsequently, water was added, and the precipitated solid was collected by filtration, dried, purified by sublimation, and 2,2′-bi (benzo [1,2-b: 4,5-b ′] diselenophene) (yellow solid) In the general formula (1), n = 2, X ¹ , X ² = Se, R ¹ , R ² = H) were obtained.
Melting point: 300 ° C. or higher, MS (EI) m / z 566 (M ⁺ , 100%),
Elemental analysis: calculated value (C ₂₀ H ₁₀ Se ₂ ) C, 42.43; H, 1.78%, measured value C, 42.39; H, 1.82%

Synthesis Example 6
1,5-dibromo-2,4-diiodobenzene was prepared in the same manner as in Synthesis Example 1 except that 1,3-dibromobenzene (manufactured by Tokyo Chemical Industry Co., Ltd.) was used instead of 1,4-dibromobenzene. (Yield 90%). Then, in a nitrogen atmosphere, this was improved from the method described in the literature [Tetrahedron Vol.59, p.2497 (2003)] (reagents: palladium chloride bis (triphenylphosphine), cuprous iodide, phenylacetylene). , Solvent: diisopropylamine) and converted to 1,5-dibromo-2,4-bis (phenylethynyl) benzene (yield 84%).

Subsequently, the obtained 1,5-dibromo-2,4-diiodobenzene (0.5 g, 1.1 mmol) was lithiated at a low temperature under an inert gas atmosphere, and selenium powder (0.17 g, 2.2 mmol) was obtained. ) As a yellow solid, 2,6-diphenyl-benzo [1,2-b: 5,4-b ′] diselenophene (in the general formula (2), n = 1, X ³ , X ⁴ = Se, R ³ , R ⁴ = phenyl) (0.41 g, 81% yield).
Melting point: 300 ° C. or higher, MS (MALDI-TOF) m / z 436 (M ⁺ , 100%),
Elemental analysis: calculated value (C ₂₂ H ₁₄ Se ₂ ) C, 60.57; H, 3.23%, measured value C, 60.58; H, 3.25%

Synthesis example 7
In Synthesis Example 6, 1,5-dibromo-2,4-diiodobenzene (0.5 g, 1.1 mmol) lithiated in the same manner as in Synthesis Example 6 except that sulfur powder was used instead of selenium powder. And sulfur powder (0.07 g, 2.2 mmol) are reacted as a yellow solid to give 2,6-diphenyl-benzo [1,2-b: 5,4-b ′] dithiophene (formula (2 ), N = 1, X ³ , X ⁴ = S, R ³ , R ⁴ = phenyl) (0.18 g, yield 48%) was obtained.
Melting point: 300 ° C. or higher, MS (MALDI-TOF) m / z 324 (M ⁺ , 100%),
Elemental analysis: calculated value (C ₂₂ H ₁₄ S ₂ ) C, 77.15; H, 4.12%, measured value C, 77.10; H, 4.18%

  Thin film devices having the structures shown in FIGS. 1A and 1B were manufactured using the compounds prepared according to Synthesis Examples 1 to 7 as the organic semiconductor material 6, respectively. In these thin film devices, the dielectric layer 5 made of silicon dioxide was formed on the silicon substrate 4 acting as the gate electrode 3 by n-doping by thermal oxidation. In manufacturing the thin film device having the structure shown in FIG. 1A, the contact channel between the source 1 and the drain 2 was defined by electron beam drawing or photolithography. The channel width was 200 μm and the channel length was in the range of 1-10 μm. The contact metal of such a device was gold.

An organic semiconductor material 6 was deposited on the dielectric layer 5 of the silicon substrate 4 by vacuum deposition at a pressure of about 1 × 10 ⁻³ Pa or less. The vapor deposition rate was 0.1 nm / s. The temperature of the substrate was adjusted by heating the copper block on which the substrate was placed.

  In the thin film device having another structure shown in FIG. 1B, the source 1 and the drain 2 are formed on the upper surface of the semiconductor layer 6 formed as described above using a shadow mask. The contact point between the source 1 and the drain 2 was 1.5 mm in width and 0.05 mm in length.

  The field-effect mobility is measured by applying a swept source / drain voltage (0 to 100 V) to a device in which a semiconductor layer is formed from the compound of each synthesis example, with the gate voltage fixed. The saturation drain-source current of the FET response curve was used for calculation. As an example of a typical FET response curve, the one obtained from the FET element of the diphenyldibenzoselenophene thin film of Synthesis Example 1 is shown in FIG. The calculation of the carrier mobility of the semiconductor complied with the description in “Semiconductor device physical characteristics and technology” [Sze, S.M., pp30-35, pp200-207 (1985)]. Table 1 below shows the results obtained by measuring the carrier mobility and on / off current ratio of the semiconductors according to Synthesis Examples 1 and 2 at room temperature using the thin film device having the structure shown in FIG. The on / off current ratio was calculated based on the currents flowing when the gate voltage was -100V on and 0V off.

＊参考例は、合成例１のセレン原子を硫黄原子に代えた２，６−ジフェニル−ベンゾ［１，２−ｂ；４，５−ｂ’］ジチオフェンに対し、合成例１と同様にして測定して得られた結果を示す。

* Reference Example was measured in the same manner as in Synthesis Example 1 for 2,6-diphenyl-benzo [1,2-b; 4,5-b ′] dithiophene in which the selenium atom in Synthesis Example 1 was replaced with a sulfur atom. The results obtained are shown below.

  The mobility of the organic semiconductor thin film is affected by the substrate temperature at the time of film formation, that is, when the film is attached. This was confirmed as follows. First, diphenyldibenzoselenophene of Synthesis Example 1 and di (biphenyl) dibenzoselenophene of Synthesis Example 2 are used as organic semiconductor materials, respectively, and these organic semiconductor materials are adhered at room temperature, 60 ° C., and 100 ° C. Various thin film devices were manufactured. Approximately 10 devices were fabricated at each of the deposition temperatures. The graph of FIG. 3 shows the average mobility of the deposited organic semiconductor thin film at various temperatures.

The device measured to obtain the graph shown in FIG. 3 has the structure shown in FIG. The graph shown in the figure shows that the substrate temperature when depositing the organic semiconductor thin film affects the mobility of the organic semiconductor thin film. The maximum mobility was observed when the substrate temperature was 60 ° C. for diphenyldibenzoselenophene of Synthesis Example 1 and when the substrate temperature was 100 ° C. for di (biphenyl) dibenzoselenophene of Synthesis Example 2. Further, the on / off current ratio at this time was 10 ⁵ .

The organic semiconductor device having the benzodichalcogenophene derivative of the present invention as an organic semiconductor material can achieve a mobility exceeding 0.1 cm ² / Vs and a high on-off current ratio (10 ⁵ or more). It is extremely useful as a light emitting device having a thin film transistor or an organic carrier transporting layer or a light emitting layer.

In addition, the production method of the present invention obtains the benzodichalcogenophene derivative of the present invention in a high overall yield (50% or more) in 3 to 5 steps from an inexpensive commercially available raw material such as 1,4-dibromobenzene. be able to. Further, since there is little impurity contamination in the synthesis process, the purification can be easily performed. Therefore, a mobility exceeding 0.1 cm ² / Vs and a high on / off current ratio (10 ⁵⁾ can be obtained by a single sublimation purification. An organic semiconductor device capable of achieving the above can be obtained.

(A) And (b) is typical sectional drawing which shows the structure of a thin-film transistor device, respectively. It is a graph which shows the FET response curve of the thin-film transistor device using diphenyl dibenzo selenophene. It is a graph which shows the average mobility of the organic-semiconductor thin film (Synthesis example 1, Synthesis example 2) attached at various temperature.

Explanation of symbols

1 source 2 drain 3 gate electrode 4 silicon substrate 5 dielectric layer 6 organic semiconductor material (organic semiconductor layer)

Claims (11)

The following general formula (1),

Wherein X ¹ and X ² are each independently a selenium atom or tellurium atom, n is an integer of 1 to 3, R ¹ and R ² are each independently a hydrogen atom, a halogen atom, or an alkyl group having 2 to 18 carbon atoms. Or an aryl group optionally having a chalcogen atom, and the aryl group includes a halogen atom, an alkyl group having 2 to 18 carbon atoms, an alkyloxy group having 2 to 18 carbon atoms, and an alkylthio group having 2 to 18 carbon atoms. A benzodichalcogenophene derivative, which may have at least one substituent selected from the group consisting of a group and an aryl group. The following general formula (2),

Wherein X ³ and X ⁴ are each independently a selenium atom or tellurium atom, n is an integer of 1 to ³ , R ³ and R ⁴ are each independently a hydrogen atom, a halogen atom, or an alkyl group having 2 to 18 carbon atoms. Or an aryl group optionally having a chalcogen atom, and the aryl group includes a halogen atom, an alkyl group having 2 to 18 carbon atoms, an alkyloxy group having 2 to 18 carbon atoms, and an alkylthio group having 2 to 18 carbon atoms. A benzodichalcogenophene derivative, which may have at least one substituent selected from the group consisting of a group and an aryl group. The following general formula (3),

Or the following general formula (4),

Wherein X ⁵ and X ⁶ are each independently a chalcogen atom, n is an integer of 1 to 3, R ⁵ and R ⁶ are each independently a hydrogen atom, a halogen atom, an alkyl group having 2 to 18 carbon atoms, or a chalcogen An aryl group which may have an atom, and the aryl group includes a halogen atom, an alkyl group having 2 to 18 carbon atoms, an alkyloxy group having 2 to 18 carbon atoms, an alkylthio group having 2 to 18 carbon atoms and an aryl group. In the production of a benzodichalcogenophene derivative represented by (which may have at least one substituent selected from the group consisting of groups)
Two substituents containing an unsaturated carbon bond separately having R ⁵ and R ^{6 at the} ends (provided that when R ⁵ and R ⁶ are hydrogen atoms, a protecting group for the hydrogen atom), X ⁵ and X 6 A benzene ring having two substituents containing ⁶ separately on the same ring, including an unsaturated carbon bond having R ⁵ (provided that when R ⁵ is a hydrogen atom, a protecting group for the hydrogen atom) A substituent containing an unsaturated carbon bond having a substituent and a substituent containing X ⁵ , and R ⁶ (provided that when R ⁶ is a hydrogen atom, a protecting group for the hydrogen atom), and X ⁶ A method for producing a benzodichalcogenophene derivative, comprising a step of condensation reaction with a substituent.   The production method according to claim 3, wherein the chalcogen atom is a selenium atom or a tellurium atom.   The compound represented by formula (3) or (4) wherein n is 2 or 3 is produced by producing a compound wherein n is 1 and then combining them. The manufacturing method as described.   The production method according to claim 5, wherein the compound represented by the general formula (3) or (4) wherein n is 1 is activated by treatment with an organometallic reagent, and then an oxidative bond formation reaction with a metal salt is used.   An organic semiconductor device, wherein at least one compound represented by the general formula (1) and / or (2) is used as an organic semiconductor material.   The organic semiconductor device according to claim 7, which is a thin film transistor having an organic semiconductor layer.   The organic semiconductor device according to claim 7, which is a light emitting device having an organic carrier transport layer or a light emitting layer. The organic-semiconductor device as described in any one of Claims 7-9 which has a field effect mobility of 0.1 cm < ² > / Vs or more. The organic semiconductor device according to claim 7, having an on / off current ratio of 10 ⁵ or more.

Images