WO2018043725A1

WO2018043725A1 - Organic semiconductor material, organic compound and organic semiconductor device

Info

Publication number: WO2018043725A1
Application number: PCT/JP2017/031671
Authority: WO
Inventors: 純一半那; タンジョウヤン; 裕明飯野
Original assignee: 国立大学法人東京工業大学
Priority date: 2016-09-02
Filing date: 2017-09-01
Publication date: 2018-03-08
Also published as: JPWO2018043725A1

Abstract

This organic semiconductor material contains at least the following: a unit A including a skeleton structure based on isoquinolino-isoquinoline (IQIQ) represented by formula (1); a fatty acid-based chain unit B connected by a single bond with unit A; and a unit C which is a hydrogen atom, or a group containing a fatty acid chain and/or a cyclic structure, unit c being connected by a single bond with unit A. The organic semiconductor material exhibits liquid crystal properties, has a deep LUMO level, and can be preferably used as an n-type organic transistor material. This invention also provides a novel compound.

Description

Organic semiconductor material, organic compound, and organic semiconductor device

The present invention relates to an organic semiconductor material and an organic compound exhibiting liquid crystallinity, and an organic semiconductor device. More specifically, the present invention exhibits liquid crystallinity and can be suitably used as an organic semiconductor (for example, an n-type organic semiconductor) in at least one of a liquid crystal phase and a crystal phase, and an organic semiconductor material and an organic semiconductor material thereof. The present invention relates to an organic semiconductor device using an organic compound.

In general, a substance having a “rod-like” molecular structure and exhibiting liquid crystallinity having an extended aromatic π-conjugated site is characterized by a relatively flexible long-chain hydrocarbon chain. In addition to being useful as a liquid crystal organic semiconductor, it has a structure similar to a soluble organic transistor material.

Actually, many organic transistor materials (eg, quarterthiophene, benzothienobenzothiophene (BTBT), anthracene derivatives) tend to exhibit a smectic liquid crystal phase in a certain temperature range. In addition, a recent report reports that these smectic liquid crystal phases and other liquid crystal phases can be uniformly formed by a wet process, are high mobility materials, and can realize high heat resistance. A liquid crystal phase such as a phase attracts attention as a material suitable as an organic transistor material (Patent Documents 1 and 2).

In organic transistors, since an organic transistor using a pentacene crystal material (Non-patent Document 1) was reported, oligothiophene (Non-patent Document 2), TIPS-pentacene (Non-patent Document 13), and benzothienobenzothiophene [ 5,10] derivatives and the like are synthesized to produce transistors.

However, since an n-type organic semiconductor material requires a material having a low LUMO level (deep LUMO level), organic semiconductor materials capable of n-type operation (electron transportable) in the atmosphere are extremely limited. There are limited reports of materials that can operate n-type transistors (Non-Patent Documents 4 to 6). For this reason, an n-type organic transistor material necessary for manufacturing a CMOS is still eagerly searched.

As a semiconductor material having a deep LUMO level, materials such as fullerene have been reported, but since fullerene has poor solubility, uniform film formation by a wet process is difficult.

WO2012 / 121393 pamphlet WO2008 / 047896 pamphlet

The main object of the present invention is to provide an organic semiconductor material exhibiting liquid crystallinity, which has a deep LUMO level and can be preferably used as an n-type organic semiconductor, which can eliminate the above-mentioned drawbacks of the prior art. It is in. Another object of the present invention is to provide an organic semiconductor device and a novel compound using the organic semiconductor material.

As a result of diligent research, the present inventor has found that a novel compound having a specific isoquinolino-isoquinoline (hereinafter sometimes abbreviated as “IQIQ”) skeleton structure is used as an “organic semiconductor material” having a deep LUMO level. And found that it is extremely effective for achieving the above-mentioned purpose.

The organic semiconductor material of the present invention is based on the above knowledge, and more specifically, a unit A having a IQIQ (isoquinolino-isoquinoline) type skeleton structure; and a carbon main chain linked to the unit A by a single bond. An aliphatic chain unit B in which one or more of the constituent carbon atoms may be substituted with an oxygen atom; a group containing an aliphatic chain and / or a cyclic structure connected to the unit A with a single bond; Or an organic semiconductor material having at least a unit C which is a hydrogen atom; wherein the organic semiconductor material exhibits liquid crystallinity.

The present invention can include, for example, the following aspects.
[1] A unit A including a skeleton structure based on isoquinolinoisoquinoline (IQIQ) represented by the following formula (1), an aliphatic chain unit B linked to the unit A by a single bond, and the unit A An organic semiconductor material having at least a group containing an aliphatic chain and / or a cyclic structure connected by a single bond, or a unit C which is a hydrogen atom; wherein the organic semiconductor material exhibits liquid crystallinity Organic semiconductor material.

[2] The unit A is represented by the following formula (2)

(In the formula, each a is independently a hydrogen atom, a single bond, or a saturated and / or unsaturated cyclic group, and the saturated and / or unsaturated cyclic group is a hydrocarbon group. Or it may contain one or more heteroatoms.)
The unit B and the unit C are each connected to two a by a single bond, and when the a is a single bond, the unit B and / or the unit C is connected to IQIQ. The organic semiconductor material according to [1], which is directly bonded by a single bond.

[3] In the formula (2), each a independently represents the following structural formula

(In the formula, R is a hydrogen atom or an aliphatic chain group.)
Each of unit B and unit C is bonded to a in such a way as to replace a substitutable site or atom of the above structure, and R in the above formula is a hydrogen atom In the case, it is substituted with R, or when R is an aliphatic chain group, the hydrogen atom of the aliphatic chain group of R can be substituted and bonded to the unit A. The organic semiconductor material according to [2].

[4] The organic semiconductor material according to any one of [1] to [3] above, wherein the unit B is an aliphatic chain group having 3 to 20 carbon atoms.

[5] The aliphatic chain of the unit C is an aliphatic chain group having 3 to 20 carbon atoms, and the group including the cyclic structure of the unit C is an aromatic group, a heterocyclic group or an aliphatic ring group. The organic semiconductor material according to any one of the above [1] to [4], which is a group containing the organic semiconductor material.

[6] The organic semiconductor material according to any one of [1] to [5], wherein the LUMO level is deeper than −3 eV.

[7] The organic semiconductor material according to any one of [1] to [6] above, wherein the solubility in toluene is 0.1 wt% or more at room temperature (25 ° C.).

[8] The organic semiconductor material according to any one of the above [1] to [7], wherein the mobility of electrons and / or holes is greater than 10 ⁻⁴ cm ² / Vs.

[9] The organic semiconductor material according to any one of [1] to [8], which exhibits properties of an n-type organic semiconductor.

[10] The organic semiconductor material according to any one of [1] to [9], wherein the organic semiconductor material exhibits properties of an n-type organic semiconductor in at least one of a liquid crystal state and a crystalline state.

[11] The organic semiconductor material according to any one of the above [1] to [10], which shows a smectic (Sm) liquid crystal phase as a developed liquid crystal phase.

[12] Unit A including a skeleton structure based on isoquinolino-isoquinoline (IQIQ) represented by the following formula (1), an aliphatic chain unit B linked to the unit A by a single bond, and the unit A An organic compound having at least a group containing an aliphatic chain and / or a cyclic structure, or a unit C which is a hydrogen atom, connected by a single bond.

[13] The unit A is represented by the following formula (2)

(In the formula, each a is independently a hydrogen atom, a single bond, or a saturated and / or unsaturated cyclic group, and the saturated and / or unsaturated cyclic group is a hydrocarbon group. Or it may contain one or more heteroatoms.)
Each of unit B and unit C is bonded to two a by a single bond, and when the a is a single bond, unit B and / or unit C is an IQIQ skeleton. The organic compound according to the above [12], which is directly bonded to a single bond.

[14] a in the formula (2) is each independently the following structural formula

(In the formula, R is a hydrogen atom or an aliphatic chain group.)
Each of unit B and unit C is substituted with R when R is a hydrogen atom, or R is an aliphatic chain group. In some cases, the organic compound according to [13] above, which can be bonded to the unit A by substituting for a hydrogen atom of an aliphatic chain group of R.

[15] The organic semiconductor material according to any one of [12] to [14] above, wherein the unit B is an aliphatic chain group having 3 to 20 carbon atoms.

[16] The aliphatic chain of the unit C is an aliphatic chain group having 3 to 20 carbon atoms, and the group including the cyclic structure of the unit C is an aromatic group, a heterocyclic group, or an aliphatic cyclic group. The organic semiconductor material according to any one of [12] to [15], which is a group containing the organic semiconductor material.

[17] The organic compound according to [12], which is represented by the following formula (3).

(Wherein a ₁ , a ₂ , a ₃ and a ₄ are each independently a hydrogen atom, a single bond, or a saturated and / or unsaturated cyclic group, And / or the unsaturated cyclic group may be a hydrocarbon group or may contain one or more heteroatoms, but at least one of a ₁ , a ₂ , a ₃ and a ₄ is a single bond Or a saturated and / or unsaturated cyclic group; at least one of R ₁ , R ₂ , R ₃ and R ₄ is each independently an aliphatic chain group, and R ₁ , R ₂ , R ₃ and R ₄ are not aliphatic chain groups, the remaining R ₁ , R ₂ , R ₃ and R ₄ can be hydrogen atoms.)

[18] The organic compound according to [17] above, wherein in formula (3), at least one of R ₁ and R ₃ is an aliphatic chain group.

[19] The above [17] to [18], wherein the aliphatic chain unit B or the aliphatic chain group is an aliphatic chain group having 3 to 20 carbon atoms. Organic compounds.

[20] 2,8-didecylisoquino [8,7-h] isoquinoline (10-IQIQ-10), 2.8-didodecylisoquino [8,7-h] isoquinoline (12-IQIQ-12) or 2. The organic compound according to any one of [12] to [19] above, which is 8-ditetradecylisoquino [8,7-h] isoquinoline (14-IQIQ-14).

[21] A layer formed by using the organic semiconductor material according to any one of [1] to [11] or the organic compound according to any one of [12] to [20] A semiconductor device comprising: a positive electrode and a negative electrode electrically connected to the semiconductor layer.

As described above, according to the present invention, an organic semiconductor material exhibiting suitable characteristics (for example, liquid crystallinity, solvent solubility, deep LUMO level, excellent semiconductor characteristics, particularly n-type organic semiconductor characteristics) can be obtained. . A semiconductor device using the organic semiconductor material is also provided. Furthermore, according to the present invention, a novel compound having a skeleton structure based on IQIQ is provided.

It is a DSC curve measured by thermal analysis suggested by 10-IQIQ-10, and a photograph of the structure observed with a polarizing microscope of 10-IQIQ-10. 2 is an X-ray diffraction chart of 10-IQIQ-10 at 140 ° C. (solid crystal). It is a DSC curve measured by suggestive thermal analysis of H12-IQIQ-12, and a photograph of the structure of 12-IQIQ-12 observed at 150 ° C. with a polarizing microscope. It is an X-ray diffraction pattern of H12-IQIQ-12, where (a) is an Sm phase at 150 ° C. and (b) is an X-ray diffraction pattern of a crystal (solid) at 130 ° C. FIG. 3 is a schematic diagram of an Sm phase X-ray diffraction pattern of H12-IQIQ-12 at 150 ° C. and a liquid crystal molecule arrangement in a liquid crystal layer. It is a UV spectrum of a chloroform solution of 12-Chrysene-12 and 12-IQIQ-12. 2 is a photoelectron yield spectrum of 12-Chrysene-12 and 12-IQIQ-12 measured at 25 ° C. by photoelectron spectroscopy. It is a transient photocurrent waveform plotted by logarithm plotting measured by TOF method at 146 ° C. of 12-IQIQ-12, and is a result of (a) positive charge and (b) negative charge photocurrent. The insets in the photocurrent waveform diagrams of (a) and (b) show the respective linear plots. Electric field strength of 12-IQIQ-12: Temperature dependence of mobility of positive charge and negative charge at 6.6 × 10 ⁴ V / cm.

Hereinafter, the present invention will be described more specifically with reference to the drawings as necessary. In the following description, “parts” and “%” representing the quantity ratio are based on mass unless otherwise specified.

(Organic semiconductor materials)
The organic semiconductor material of the present invention comprises a unit A having an isoquinolino-isoquinoline (IQIQ) type skeleton structure; an aliphatic chain unit B (carbon atoms constituting a carbon main chain) linked to the unit A by a single bond; One or more of them may be substituted with “O (oxygen atom)”; a group containing an aliphatic chain and / or a cyclic structure connected to the unit A by a single bond, or a hydrogen atom An organic semiconductor material containing an organic compound having at least a unit C, wherein the organic semiconductor material exhibits liquid crystallinity. “The organic semiconductor material exhibits liquid crystallinity” means that the organic semiconductor material exhibits liquid crystallinity at any temperature. The organic semiconductor material of the present invention exhibits electron transport properties, and can be used as an excellent semiconductor particularly in a liquid crystal phase or a (solid) crystal phase.

The organic compound constituting the organic semiconductor material of the present invention is preferably a compound in which unit B and unit C are bonded to both ends of unit A by a single bond. That is, the organic compound constituting the organic semiconductor material of the present invention can have a configuration of <unit C> − <unit A> − <unit B>.

(Unit A)
The “unit A” of the organic compound constituting the organic semiconductor material of the present invention will be described.
The unit A is a unit including a skeleton structure based on isoquinolino-isoquinoline (IQIQ) represented by the following formula (1). The skeleton structure based on isoquinolino-isoquinoline (IQIQ) can have a group as described below. Unit A has a modified structure of IQIQ of formula (1) in that unit B and unit C are connected by a single bond. The organic semiconductor material of the present invention includes a skeletal structure based on isoquinolino-isoquinoline (IQIQ) as an extended aromatic π-conjugated system, so that a semiconductor property having a deeper LUMO level, particularly a LUMO level deeper than 3 eV can be obtained. It has the effect that it can utilize suitably as an n-type organic semiconductor.

“Unit A” may be composed of “IQIQ” represented by the formula (1) alone, and the following formula (2)

Wherein each a is independently a hydrogen atom, a single bond, or a saturated and / or unsaturated cyclic group, the cyclic group being a hydrocarbon group or one or more May include heteroatoms; at least one a is the cyclic group.)
As shown in the above, at least one “cyclic group a” (since at least one a is a cyclic group, all a or a that is a cyclic group may be referred to as “cyclic group a”) is included in the IQIQ. Some may be connected by a single bond. In the case of the unit A including the cyclic group a, in the organic semiconductor material of the present invention, each of the unit B and the unit C is bonded to two a in the above formula by a single bond, so that the unit B and / or When the a to which unit C is bonded is a saturated and / or unsaturated cyclic group, unit B and / or unit C will be bonded to the cyclic group with a single bond, and unit B and When the a itself to which the unit C is bonded is a single bond, the unit B and / or the unit C is directly bonded to the IQIQ skeleton of the unit A with a single bond. In the embodiment in which the unit A has such a cyclic group a, the liquid crystallinity is effectively expressed by the property of the cyclic group a.

In addition, “unit A” includes at least one other substitution in the IQIQ skeleton in place of the cyclic group a or in addition to the cyclic group a, particularly at positions R ₅ to R _{8 in} the following formula (4). A group, particularly an aliphatic group, may be linked by a single bond. This substituent, particularly an aliphatic group, can be the same as the substituent and the aliphatic group constituting the units B and C described later. In the embodiment in which the unit A has such a substituent, it is effective to suitably exhibit liquid crystallinity depending on the nature of the substituent.

(Suitable cyclic group a)
In the above formula (2), at least one of the cyclic groups a is a saturated and / or unsaturated cyclic group. The cyclic structure constituting the cyclic group a is preferably a 5-membered ring and / or a 6-membered ring and / or a composite structure thereof. The cyclic group a may be a hydrocarbon group or may contain one or more heteroatoms (for example, O, N and / or S).

In the present invention, the “suitable cyclic group a” can include, for example, the following structure.

In the above formula, R is a hydrogen atom or an aliphatic chain group. It is preferably a hydrogen atom. In addition to the alkyl group, the aliphatic chain group may contain an oxygen atom in the main chain, and the number of carbon atoms in R is preferably 20 or less. Each of the units B and C is substituted when R in the above formula is a hydrogen atom, or when R is an aliphatic chain group, the aliphatic chain group of the R It may be bonded to the unit A in the form of substitution with a hydrogen atom.

In the organic semiconductor material of the present invention, unit B and unit C are bonded to unit A by a single bond. When the unit B and the unit C are “coupled by a single bond” to the unit A, the unit B and the unit C are single-bonded to the carbon atom constituting the skeleton structure including the IQIQ of the unit A. Therefore, a single bond (directly between unit B and unit C and the carbon atom is used in the form of substitution with a hydrogen atom bonded to the carbon atom in the skeleton structure represented by the above formulas (1) to (3). Bond) is formed. That is, it should be noted that the structures represented by the formulas (1) to (3) are structures before the unit B and the unit C are substituted and bonded. The carbon atom constituting the skeletal structure in which the unit B and the unit C are bonded by a single bond is the carbon atom constituting the IQIQ itself represented by the formula (1), as well as represented by the formula (2) and the formula (3). It may be a cyclic group a bonded to IQIQ or a carbon atom constituting the substituents R ₅ to R ₈ .

In the present invention, the organic compound has a structure of <unit C>-<unit A>-<unit B>, that is, a chain molecule in which unit B is bonded to one end of unit A and unit C is bonded to the other end. It preferably has a structure. The both ends of the unit A are the 2, 3, 8, and 9 positions of IQIQ (positions where a is bonded to the pyridine ring of the formula (2)). Unit B is coupled to one end of unit A (eg, at least one of

positions

2 and 3 of IQIQ), and unit C is coupled to the other end (eg, at least one of positions 8 and 9 of IQIQ). And the unit at the remaining end (the position of a in formula (2), that is, if there are positions where units B and C are not coupled among

positions

2, 3, 8, and 9 of IQIQ) B and / or unit C may or may not be combined. Further, the unit B and the unit C are bonded directly to the carbon atoms at the 2nd and 8th positions (position to which a is bonded) of IQIQ represented by the following formula (5) or bonded to the 2nd and 8th position carbon atoms. It is preferably bonded to a carbon atom of the cyclic group a.

(Unit B)
In the organic semiconductor material of the present invention, “unit B” is an aliphatic chain group connected to unit A by a single bond. In the organic semiconductor material of the present invention, the unit B is indispensable, and the unit B, which is a relatively flexible long chain, is bonded to the rigid unit A, so that the liquid crystallinity of the material can be suitably expressed. , Effective in improving solubility.

The aliphatic chain group may be either a saturated or unsaturated aliphatic chain group. For example, the main chain is a saturated or unsaturated group (for example, an alkyl group) composed of carbon atoms, or the carbon thereof. It is preferably a saturated or unsaturated aliphatic chain group containing “O (oxygen atom)” in the main chain composed of atoms. The number of carbon atoms constituting the aliphatic chain of unit B is preferably 3-20, more preferably 10-14, and particularly preferably 12. If the number of atoms of the aliphatic chain group is 2 or less, it is difficult to impart flexibility to the molecule, and it may exceed 20, but if it exceeds 20, it may be difficult to obtain.

In one preferred embodiment of the present invention, the aliphatic chain group constituting “unit B” is a C ₃ to C ₂₀ alkyl group.

In another aspect suitable for the present invention, one or more “O (oxygen) atoms” in the aliphatic chain group of “unit B” may be present in the carbon main chain. A preferable “unit B” in this embodiment has one or more structures represented by the following formula as its partial structure. The terminal of the aliphatic chain group having this partial structure is —CH ₃ .
(-X ^1- (CH ₂ ) _r -X ^2- ),
(In the formula, X ¹ and X ² ═O or CH ₂ , and r is an integer of 1 to 19, except for the aspect of X ¹ ═X ² ═O (oxygen atom)). The number of carbon atoms in the main chain is preferably 3-20.

More specifically, the structure of such a suitable “unit B” is exemplified as follows. In the following formula, X = O or CH ₂ , n + m = 3 to 19, p + n + m = 3 to 19, or p +... + N + m = 3 to 19, and m and n may include 0 Good. The number of carbon atoms in the main chain is preferably 3-20.
-(CH ₂ ) _n -X- (CH ₂ ) _m -CH ₃ ,
— (CH ₂ ) _p —X— (CH ₂ ) _n —X— (CH ₂ ) _m —CH ₃ ,
(Omitted)
— (CH ₂ ) _p —X—... —X— (CH ₂ ) _n —X— (CH ₂ ) _m —CH ₃ ,

In the present invention, when “O atom” is included in the structure of “unit B”, there is an advantage that the compatibility (solubility) between the organic semiconductor material of the present invention and the organic solvent becomes better. This is because organic solvents (excluding pure hydrocarbon solvents) are generally not apolar at all and often have a certain degree of polarity.

As described above, unit B is bonded to one of the ends of unit A, that is, any of

positions

2, 3, 8, and 9 (positions where a is bonded to the pyridine ring of formula (2)) of IQIQ. Is preferred. When unit B is coupled to the end of unit A, unit A is present at the end of those structures in the structures shown in the above formulas (1) to (3) or the structure shown as an example of cyclic group a. A structure in which unit B is substituted for a hydrogen atom bonded to a carbon atom can be obtained.

The aliphatic chain group constituting the unit B can be the same group as the aliphatic chain group that may be contained in the unit A. Therefore, when unit A includes an aliphatic chain group and the aliphatic chain group satisfies the requirements of unit B, the aliphatic chain group of unit B is different from the aliphatic chain group of unit A. It may be additionally present, or the aliphatic chain group of the unit A itself may be the aliphatic chain group of the unit B, but the aliphatic chain group of the unit A When itself constitutes the aliphatic chain group of unit B, the aliphatic chain group constituting the aliphatic chain group of unit B is not regarded as a part constituting unit A.

When the unit A has a cyclic group a added to the IQIQ skeleton, the cyclic group a has an aliphatic chain group R, and the unit B is linked to the aliphatic chain group of the cyclic group a, the cyclic group a The aliphatic chain group R and the aliphatic chain group of the unit B preferably have 3 to 20 carbon atoms in their main chain. The reason why the total length of the aliphatic chain group formed by combining unit A and unit B is preferably 3 to 20 carbon atoms is that the length of the aliphatic chain group of unit B is described. The same reason as above.

(Unit C)
In the organic semiconductor material of the present invention, “unit C” is a group containing a hydrogen atom, an aliphatic chain, or a cyclic structure connected to unit A by a single bond. In the organic semiconductor material of the present invention, the unit C can suitably exhibit the liquid crystal properties of the organic semiconductor material according to the properties of the unit C.

In the definition of the unit C, the “group containing a cyclic structure” includes an aromatic group (for example, a phenyl group), a heterocyclic group (for example, a thiophene group), or an aliphatic group (for example, a cyclohexyl group). it can. The “group containing a cyclic structure” in the unit C can be the same as the cyclic group a in the unit A. The meaning of the “aliphatic chain” in the “group containing an aliphatic chain” in the unit C is the same as that described for the aliphatic chain group in the “unit B”.

Examples of the aromatic group in the group containing a cyclic structure include phenyl, naphthyl, anthranyl, phenanthrenyl, fluorenyl, indenyl, azulenyl, biphenyl, terphenyl, cyclohexylphanyl, and naphthylphenyl.
Examples of the heterocyclic group in the group containing a cyclic structure include thienyl, benzothienyl, naphthothienyl, furyl, oxadiazolyl, thiazoyl, thiadiazoyl, benzofuranyl, pyrrolyl, pyrazolyl, imidazolyl, pyridyl, pyrazinyl, pyrimidunyl, pyridazinyl, indolyl, quinolyl, Examples include isoquinolyl, phthalazinyl, naphthyridinyl, quinoxalinyl, quinazolinyl, tinolinyl, carbazoyl, acridinyl, phenanthridinyl, phenazinyl, and fetalidinyl.
Examples of the aliphatic group in the group including a cyclic structure include cyclopentyl, cyclohexyl, cycloheptyl, phenylcyclohexyl, and the like, and some of the structures include heteroatoms such as O, S, and N and unsaturated bonds. .

As described above, the unit C is preferably bonded to the end of the unit A, particularly to

IQIQ positions

2, 3, 8, and 9 (positions where a is bonded to the pyridine ring of the formula (2)). When unit C is bonded to unit A by a single bond, unit C is bonded to unit A by substituting hydrogen atoms bonded to the carbon atoms constituting unit A shown in formulas (1) to (3). become. The unit C is preferably connected to the end of the unit A opposite to the end to which the unit B is connected.

The group containing a cyclic structure or the group containing an aliphatic chain constituting the unit C can be the same group as the cyclic group or the aliphatic chain group that may be contained in the unit A. Therefore, when the unit A includes a cyclic group or an aliphatic chain group, and the cyclic group or the aliphatic chain group satisfies the requirements of the unit C, the cyclic group or the aliphatic chain group of the unit C is The cyclic group or aliphatic chain group may be present separately from the cyclic group or aliphatic chain group that the unit A has, or the cyclic group or aliphatic chain group of the unit A itself is the cyclic group or aliphatic chain group of the unit C. However, when the cyclic group or aliphatic chain group of unit A itself constitutes the cyclic group or aliphatic chain group of unit C, the cyclic group or aliphatic system of unit C may be used. The cyclic group or aliphatic chain group constituting the chain group is not regarded as a part constituting the unit A.

When the unit A has a cyclic group a added to the IQIQ skeleton, the cyclic group a has an aliphatic chain group R, and the unit C is linked to the aliphatic chain group of the cyclic group a, the cyclic group a The aliphatic chain group R and the aliphatic chain group of unit C preferably have 3 to 20 carbon atoms in their main chain. The reason why the total length of the aliphatic chain group formed by combining unit A and unit C is preferably 3 to 20 carbon atoms is that the length of the aliphatic chain group of unit B is described. The same reason as above.

(Specific structural example of suitable organic semiconductor material)
A preferred example of the structure of an organic compound having a configuration of the organic semiconductor material of the present invention, that is, an organic compound having a configuration of <unit C> − <unit A> − <unit B> is represented by the following structural formula (3). Street.

In the formula, a ₁ , a ₂ , a ₃ and a ₄ are each independently a hydrogen atom, a single bond, or a saturated and / or unsaturated cyclic group, The unsaturated cyclic group may be a hydrocarbon group or may contain one or more heteroatoms, but at least one of a ₁ , a ₂ , a ₃ and a ₄ is a single bond Or a saturated and / or unsaturated cyclic group; at least one of R ₁ , R ₂ , R ₃ and R ₄ is each independently an aliphatic chain group, R ₁ , R _{When any of 2} , R ₃ and R ₄ is not an aliphatic chain group, the remaining R ₁ , R ₂ , R ₃ and R ₄ can be hydrogen atoms.

In the above formula, R ₁ = <unit C>, R ₃ = <unit B>, or conversely, R ₁ = <unit B>, R ₃ = <unit C> is possible. As described above, the organic compound in which the units A, B, and C are bonded in such a form is preferable. Note that R ₁ and R ₃ may be the same (ie, symmetric) or different (ie, asymmetric). On the other hand, R ₂ and R ₄ may be a hydrogen atom, an aliphatic chain, or a group containing a cyclic structure. For example, R ₂ = R ₄ = H may be preferable. R ₂ and R ₄ may be the same (ie, symmetric) or different (ie, asymmetric). In the above description, the unit A is IQIQ alone. However, as described above, in the structural formula (5), at least one of R ₁ to R ₄ , particularly R ₁ and R ₃ is located. Two cyclic groups a may be bonded.

Suitable structures of the organic compound having the structure of the organic semiconductor material of the present invention, that is, the organic compound having the structure of <unit C> − <unit A> − <unit B> are exemplified below.
H- <unit A> -alkyl group alkyl group- <unit A> -alkyl group phenyl group- <unit A> -alkyl group thiophene group- <unit A> -alkyl group In the above, unit A is IQIQ skeleton alone There may be a composite structure such as IQIQ skeleton- (cyclic group, for example, phenylene group). At this time, for example, it has a structure of thiophene group-IQIQ skeleton-phenylene group-alkyl group.

An example of the organic compound having such a preferable structure can be represented by the following structural formula (3 ′).

(Wherein, a ₁ and a ₃ are each independently a hydrogen atom, a single bond, or a saturated and / or unsaturated cyclic group, and the saturated and / or unsaturated The cyclic group may be a hydrocarbon group or may contain one or more heteroatoms; _one of R ₁ and R ₃ is an aliphatic chain group (eg, an alkyl group), and R ₁ and R The remainder of ₃ is a hydrogen atom, an aliphatic chain group (eg, an alkyl group), a group containing a cyclic structure (eg, a phenyl group), or a cyclic hydrocarbon group containing one or more heteroatoms (eg, a thiophene group). Can do.)

(Liquid crystalline, crystalline)
In the present invention, “the organic semiconductor material exhibits liquid crystallinity” means that the organic semiconductor material exhibits liquid crystallinity in “any temperature range” in which the organic semiconductor material exhibits semiconductivity. The liquid crystallinity can be confirmed by various methods, and can be confirmed by, for example, observation with a polarizing microscope, or a combination of observation with a polarizing microscope, suggested thermal analysis, and X-ray diffraction. When the organic material is a material capable of exhibiting liquid crystallinity, it is possible to control molecular orientation in an aggregated state and realize excellent semiconductor characteristics. Although it has solubility as an excellent characteristic of liquid crystallinity, solubility can be easily confirmed by dissolving in a solvent.

The organic semiconductor material of the present invention exhibits liquid crystallinity, but is preferably in a liquid crystal or solid crystal state. It is more preferable to use higher-order smectic liquid crystals such as smectic liquid crystals, SmE, SmI, SmH, and SmK. Since the organic semiconductor material of the present invention is in a state of either a liquid crystal or a solid crystal, it can control molecular orientation and exhibits excellent semiconductor characteristics as compared with a case where liquid crystallinity is not exhibited. The liquid crystal can be confirmed by, for example, polarization microscope texture (texture) observation, a combination of a polarization microscope, suggested thermal analysis, and X-ray diffraction analysis. The solid crystal phase can be confirmed by, for example, X-ray diffraction analysis. Can do. Refer to the following literature for details.

(Semiconductor characteristics)
The organic semiconductor material of the present invention “shows electronic conductivity”. A well-known general evaluation method for semiconductor characteristics is a method in which mobility is directly obtained by the TOF method or a mobility is obtained by fabricating a transistor (FET). The latter is a widely used method for evaluating crystalline thin film materials. However, especially in the case of n-channels, that is, when electrons are carriers, there are significant restrictions, and it is necessary to select electrode materials and insulating film materials appropriately. There is.

"Ion conduction / Electronic conduction"
In the conduction of the liquid crystal phase, the evaluation of “ion conduction / electronic conduction” is important, and when using a liquid crystal having high fluidity as an organic semiconductor, confirmation thereof is necessary.

Generally, liquid crystal substances include high-molecular liquid crystals and low-molecular liquid crystals. In the case of high-molecular liquid crystals, the liquid crystal phase generally has a high viscosity, so that ion conduction tends not to occur. On the other hand, in the case of a low-molecular liquid crystal, when ionized impurities are present, a low-order liquid crystal having a strong liquid property such as a nematic phase (N phase), a smectic A phase (SmA phase, hereinafter described in the same manner) or an SmC phase. In the phase, ionic conduction tends to be induced. The term “ionized impurity” as used herein refers to an electrically active impurity (that is, a HOMO level, a LUMO level, or both of them, which can become a trap of ions and charges generated by dissociation of ionic impurities. An impurity whose level is between the HOMO and LUMO levels of a liquid crystal substance is ionized by photoionization or charge trapping (for example, M. Funahashi and J. Hanna, Impurity effect on charge carrier transport in smectic liquid crystals, Chem. Phys. Lett., 397,319-323 (2004), H. Ahn, A. Ohno, and J. Hanna, Detection of Trace Amount of Impurity in Smectic Liquid Cry Appl. Phys., Vol. 44, No.6a, 2005, pp.3764-37687).

(LUMO level)
From the viewpoint of applying the organic semiconductor material according to the present invention to a device, the HOMO and LUMO of the core part (in the present invention, the π-electron conjugate part including the IQIQ skeleton part, that is, the part related to charge transport, particularly IQIQ itself). The energy level of becomes important. In general, the HOMO level of an organic semiconductor is determined by dissolving a test substance in a dehydrated organic solvent such as dichloromethane to a concentration of, for example, 1 mmol / L to 10 mmol / L, and adding a supporting electrolyte such as a tetrabutylammonium salt. Add about 0.2 mol / L, insert a working electrode such as Pt, a counter electrode such as Pt, and a reference electrode such as Ag / AgCl into this solution, then sweep at a rate of about 50 mV / sec with a potentiostat, and CV curve The HOMO level and LUMO level can be estimated from the difference between the peak potential and the reference potential, for example, a known substance such as ferrocene.

If the HOMO level or LUMO level is outside the potential window of the organic solvent used, the HOMO-LUMO energy gap is determined from the absorption edge of the UV-visible absorption spectrum, and subtracted from the measured level. The level and LUMO level can be estimated. This method can be referred to J. Pommerehne, H. Vestweber, W.ussGuss, R. F.rtMahrt, H. Bassler, M. Porsch, and J. Daub, Adv. Mater., 7, 551 (1995). it can.

In general, the HOMO and LUMO levels of an organic semiconductor material provide a measure of electrical contact with the anode and cathode, respectively, and charge injection is limited by the size of the energy barrier determined by the difference from the work function of the electrode material. So be careful. The work function of a metal is often silver (Ag) 4.0 eV, aluminum (Al) 4.28 eV, gold (Au) 5.1 eV, calcium (Ca) 2.87 eV, as examples of materials used as electrodes. Chromium (Cr) 4.5 eV, copper (Cu) 4.65 eV, magnesium (Mg) 3.66 eV, molybdenum (Mo) 4.6 eV, platinum (Pt) 5.65 eV, indium tin oxide (ITO) 4. 35 to 4.75 eV and zinc oxide (ZnO) 4.68 eV. From the above viewpoint, the difference in work function between the organic semiconductor material and the electrode substance is preferably 1 eV or less, more preferably 0.8 eV or less, and still more preferably 0.6 eV or less. As for the work function of the metal, the following documents can be referred to as necessary.
Literature A: Handbook of Chemistry Fundamentals Revised 5th Edition II-608-61014.1b Work Function (Maruzen Publishing Co., Ltd.) (2004)

Since the HOMO and LUMO energy levels are affected by the size of the conjugated π-electron system in the core, the size of the conjugated system can be used as a reference when selecting materials. As a method for changing the HOMO and LUMO energy levels, it is effective to introduce, for example, an electron-withdrawing group such as F, another halogen element, or a cyano group into the core portion.

(Screening method)
In the present invention, a substance that exhibits a higher-order smectic liquid crystal phase and is useful as an organic semiconductor can be screened as necessary from among compounds satisfying the above-described molecular design. In this screening, basically, when used as an organic semiconductor in a liquid crystal phase, a higher order smectic phase is expressed, and when used as an organic semiconductor in a crystal phase, when cooled from a temperature higher than the crystal phase temperature, It is preferable to select one that does not develop a low-order liquid crystal phase adjacent to the crystal phase. This selection method can select a substance useful as an organic semiconductor material by making a determination according to a “screening method” described later.

(Specific screening method)
This can be easily determined by the screening method (determination method) described below. For details of each measurement method used in this screening method, the following documents can be referred to as necessary.

Reference B: How to use a polarizing microscope: Experimental Chemistry 4th Edition, Volume 1, Maruzen, P429-435
Literature C: Evaluation of liquid crystal materials: Experimental Chemistry Course 5th edition, Volume 27, P295-300, Maruzen Literature D: "Introduction to Liquid Crystal Science Experiments", Japanese Liquid Crystal Society, P1-P10, Sigma Publishing

(S1) After the isolated test substance is purified by column chromatography and recrystallization, it is confirmed by thin layer chromatography on silica gel that the test substance shows a single spot (that is, not a mixture).

(S2) Using a capillary phenomenon, the sample heated in the isotropic phase is injected into a 15 μm-thick cell in which a slide glass is bonded through a spacer. Once the cell is heated to the isotropic phase temperature, the texture is observed with a polarizing microscope, and it is confirmed that no dark field is formed in a temperature region lower than the isotropic phase. This indicates that the molecular long axis is horizontally oriented with respect to the substrate, which is a requirement for subsequent texture observation.

(S3) While cooling the cell at an appropriate temperature drop rate, for example, a rate of about 5 ° C./min, observe the texture with a microscope. At this time, if the cooling rate is too high, the formed structure becomes small and detailed observation becomes difficult, so the temperature is increased to the isotropic phase again, the cooling rate is adjusted, and the structure is easily observed. The condition that the size of the tissue is easily 50 μm or more is set.

(S4) Under the conditions set in (S3) above, the texture is observed while cooling from the isotropic phase to room temperature (20 ° C.). When the sample crystallizes in the cell during this period, cracks and voids are generated as the lattice contracts, and black lines or regions having a certain size appear in the observed texture. When a sample is injected, a black area (generally round) similar to the presence of air is generated locally, but the black lines and areas generated by crystallization appear distributed in the tissue and at the boundary so that they can be easily distinguished. it can. These can be easily distinguished from other tissues found in the texture because no disappearance or color change is observed even when the polarizer and the analyzer are rotated. When the sample shows a nematic phase, a characteristic schlieren texture expressed as a pincushion is observed (see FIG. 3: typical schlieren texture). When a sample shows a SmA phase or an SmC phase, a fan-like texture A characteristic texture having a uniform structure is observed in the fan-shaped area (see FIG. 4: a typical fan-like texture), and can be easily determined from the characteristic texture.

As a special case, in the material that transitions from SmA phase to SmB phase, SmC phase to SmF, SmI phase, the visual field changes instantaneously at the phase transition temperature, but the phase transition texture almost changes. In some cases, the texture of the formed SmB phase, SmF phase, and SmI phase may be mistaken for the SmA phase and the SmC phase, so care should be taken. In that case, it is important to be aware of the instantaneous visual field changes seen at the phase transition temperature. When this confirmation is necessary, after confirming the number of intermediate phases by DSC, X-ray diffraction is measured in each temperature region, and a high angle region peculiar to each phase (15-30 in the determination of θ-2θ). If the presence or absence of a peak is confirmed, the SmA phase, the SmC phase (no peak), the SmB phase, the SmF phase, and the SmI phase (all have a peak) can be easily determined.

(S5) A material in which no black structure is observed by texture observation with a polarizing microscope at room temperature (20 ° C.) can be used as an organic semiconductor material. Therefore, this substance is a higher-order liquid crystal phase or crystal at room temperature. Regardless of the phase (including metastable crystalline phase), it shall be treated as a category of the present invention.

(LUMO screening)
The LUMO energy level is obtained by dissolving a test substance in an organic solvent such as dehydrated THF, adding about 0.2 mol / L of a supporting electrolyte such as tetrabutylammonium salt, and adding a working electrode such as Pt and Pt to this solution. After inserting a counter electrode and a reference electrode such as Ag / AgCl, the potentiostat is swept at a speed of about 50 mV / sec, and a CV curve is drawn, and the peak potential appears at a voltage lower than about -1.8V. It can be estimated that the LUMO level is deeper than about -3 eV.

(Solubility screening)
To measure the presence or absence of solubility of 0.1 wt% or more in toluene at room temperature, put about 5 mg of the test substance and about 5 g of toluene in a sample tube, heat it moderately on a hot stage, etc., and then dissolve it in toluene once. After cooling to room temperature (25 ° C.) and holding at room temperature for 1 hour, if no crystals appear, it can be judged that the solubility is 0.1 wt% or more.

In the present invention, a liquid crystal material having an isoquino [8,7-h] isoquinoline (IQIQ) skeleton, which is a nitrogen-containing condensed ring, is designed and actually synthesized, and its phase transition behavior, energy level, optical characteristics, The charge transport properties were investigated. An organic semiconductor material (or organic compound) having such a skeleton and also having liquid crystallinity is a novel organic compound by itself in that it has an isoquino [8,7-h] isoquinoline (IQIQ) skeleton. .

(New compound)
According to the present invention, a novel organic semiconductor material exhibiting the above-described liquid crystallinity is provided. However, the organic semiconductor material is a novel compound as the organic compound itself.

Therefore, according to the present invention, a unit A including a skeleton structure based on isoquinolino-isoquinoline (IQIQ) represented by the following formula (1) and a carbon main chain linked to the unit A by a single bond are formed. One or more carbon atoms optionally substituted with an oxygen atom, an aliphatic chain unit B, a group containing an aliphatic chain and / or a cyclic structure connected to the unit A with a single bond, or hydrogen An organic compound having at least unit C as an atom is provided.

Since the chemical structure of this novel organic compound can be the same as that described for the organic semiconductor material of the present invention described above, repeated description is omitted, but the description above or below is referred to as necessary. The

One preferred embodiment of the novel organic compound of the present invention is represented by the following formula (3).

(Wherein a ₁ , a ₂ , a ₃ and a ₄ are each independently a hydrogen atom, a single bond, or a saturated and / or unsaturated cyclic group, And / or the unsaturated cyclic group may be a hydrocarbon group or may contain one or more heteroatoms, but at least one of a ₁ , a ₂ , a ₃ and a ₄ is a single bond Or a saturated and / or unsaturated cyclic hydrocarbon group; at least one of R ₁ , R ₂ , R ₃ and R ₄ is each independently an aliphatic chain group, R ₁ , When any of R ₂ , R ₃ and R ₄ is not an aliphatic chain group, the remaining R ₁ , R ₂ , R ₃ and R ₄ can be hydrogen atoms.)

In one embodiment, the organic compound of the present invention has the following formula (6):

(In the formula, at least one of R ₁ , R ₂ , R ₃ and R ₄ is each independently an alkyl group having 3 to 20 carbon atoms or other aliphatic chain group, and R ₁ , R ₂ , R ₃ and R ₄ are not aliphatic chain groups, the remaining R ₁ , R ₂ , R ₃ and R ₄ can be hydrogen atoms.)
Can be.

In the above formulas (3) and (6), at least one of R ₁ , R ₂ , R ₃ and R ₄ is each independently an aliphatic chain group described in Unit B or Unit C, particularly a carbon atom. An aliphatic chain group having a number of 3 to 20 and containing one or more oxygen atoms, such as — (CH ₂ ) _n —X— (CH ₂ ) _m —CH ₃ (wherein X═O or CH ₂ N + m = 3 to 19, and m and n may include 0), but any of R ₁ , R ₂ , R ₃ and R ₄ is not an aliphatic chain group The remaining R ₁ , R ₂ , R ₃ and R ₄ can be hydrogen atoms.

Suitable examples of the organic compound of the present invention include 2,8-didecylisoquino [8,7-h] isoquinoline (10-IQIQ-10), 2.8-didodecylisoquino [8,7-h] isoquinoline ( 12-IQIQ-12) or 2.8-ditetradecylisoquino [8,7-h] isoquinoline (14-IQIQ-14).

The organic compound of the present invention (and / or the organic semiconductor material of the present invention) is useful as a liquid crystal material, an organic semiconductor material, or the like. The method for producing the organic compound of the present invention (and / or the organic semiconductor material of the present invention) is not particularly limited, but the following production method can be suitably used from the viewpoint of simplicity.

(Production method)
As shown in Examples described later, the organic compound of the present invention can be suitably obtained according to the following “Synthesis Scheme I”.

According to the above synthesis scheme, the raw material compounds (compound 1, compound 2 and compound 3 shown in the synthesis scheme) can be prepared, and then the compound of the present invention (compound 4 shown in the synthesis scheme I) can be synthesized.

More specifically, the outline of the synthesis method of the above compounds (Compound 1, Compound 2, Compound 3, Compound 4) is as follows.

The key synthetic intermediate, 2,6-dibromonaphthalene-1,5-dicarbaldehyde (compound 1), (i) First, 1,5-dimethylnaphthalene was added dropwise to a bromine-containing methylene chloride solution. To give 2,6-dibromo-1,5-dimethylnaphthalene; (ii) N-bromosuccinimide and AIBN are then added to a carbon tetrachloride solution of 2,6-dibromo-1,5-dimethylnaphthalene; Heat to reflux to obtain 2,6-dibromo-1,5-dibromomethylnaphthalene; (iii) Next, a mixture of 2,6-dibromo-1,5-dibromomethylnaphthalene and calcium carbonate, 1,4-dioxane Is heated to reflux to obtain 2,6-dibromo-1,5-dihydroxymethylnaphthalene; (iv) Next, the slurry of silica gel and pyridinium chlorochromate in anhydrous methylene chloride is subjected to 2,6- Dibromo-1,5-dihydroxymethylnaphthalene can be added and heated to reflux to obtain 2,6-dibromo-1,5-diformylnaphthalene (Compound 1). Reference can be made to the literature (Y. Ma, Q. Zheng, Z. Yin, D. Cai, S. Chen, C. Tang. Macromolecules. 2013, 46, 4813) for conditions of these synthetic reactions.

Next, as examples of alkynes having various substituents R in the compound 1 obtained above, for example, 1-alkynes such as 1-dodecine and 1-tetradecine, so-called Sonogashira reaction from 1-alkyne. Can give 2,6-diarsynylnaphthalene-1,5-dicarbaldehyde (compound 2). If the substituent R of the R-1-alkyne having the substituent R is various organic groups (organo groups) other than alkyl groups, particularly organic groups constituting the units B and C, the Sonogashira reaction 2,6-Diorganylnaphthalene-1,5-dicarbaldehyde (Compound 2) having various substituents (organo groups) R other than alkyl groups can be obtained. For “typical Sonogashira reaction conditions”, the literature (A. V. Malkov, M. M. Westwater, A. Gutnov, P. Ramirez-Lopez, F. Friscourt, A. Kadicikova, J. Hodacova, Z. Randkovic, M. Kotora, P. Kocovsky, Tetrahedron, 2008, 64, 11335).

When an asymmetric compound is produced using the mixture of R, it is separated by a recrystallization method, column chromatography, or a combination thereof.

Next, the compound 2 obtained above is condensed with benzyloxyammonium chloride (BnONH ₂ .HCl) in the presence of NaOAc to obtain an oxime derivative (compound 3). Regarding the reaction conditions in this case, literature (S. Hwang, Y. Lee, P. H. Lee, S. Shin, Tetrahedron Lett. 2009, 50, 2305) can be referred to if necessary.

Finally, the target compound 4 is obtained by a cyclization reaction of the compound 3 with a cocatalyst of AgOTf and TfOH. They can be easily isolated as colorless crystals and purified by column chromatography and recrystallization. The structure of the resulting compound can be confirmed by a 1H NMR spectrum and a high resolution mass spectrometer.

In the case of the types of units B and C and the cyclic group a of unit A, the synthesis method is basically the same as that in Scheme 1, but only one bromine is supported in the Sonogashira reaction of compound 1, which is a key intermediate. The product reacted with the alkyne compound is first isolated and then used to synthesize the remaining bromo group and the alkyne compound corresponding to the final product by the same coupling reaction by Sonogashira reaction. Can do.

In the above synthesis scheme, various substituents such as an alkyl group and an aryl cage can be introduced at positions 3 and 9 of IQIQ by performing various known substitution reactions on the heterocyclic ring with respect to compound 4. . Known substitution reactions include those that selectively substitute the 3-position of pyridine and the 4-position of isoquinoline, such as J. Org. Chem., 53 (11), 2653-5 (1988) and J. Amer. Chem. Soc., 93 (5) 1294-6 (1971) can be used to synthesize compounds in which two B and C are substituted on the same pyridine unit of IQIQ.

Also, the organic compound of the present invention can be suitably obtained by “Synthesis route 1” or “Synthesis route 2” shown below.

These synthetic routes are modifications of the above-mentioned synthetic scheme I, and without using compound 1 which is a key intermediate, compound 2 of scheme 1 is obtained by another route. It is a synthetic scheme as a substance.

(Organic semiconductor device)
The organic semiconductor material of the present invention is an organic semiconductor material that exhibits liquid crystallinity, has excellent solubility in a solvent, has high mobility, and has a deep LUMO level. In addition, since it has a deep LUMO level, it can be used not only as an organic transistor but also as an n-type organic semiconductor having an electron transport property. The semiconductor device includes a layer formed using the novel organic semiconductor material or the novel organic compound of the present invention as a semiconductor layer, and includes a positive electrode and a negative electrode electrically coupled to the semiconductor layer. Features.

Therefore, it is possible to produce useful semiconductor devices other than transistors, such as organic EL and organic solar cells, using the organic semiconductor material of the present invention.

For example, the organic semiconductor material of the present invention is expected to be used as a high-mobility charge injection / transport layer when used in an organic EL, and also has a deep HOMO level, so it works as a hole blocking layer and is advantageous for charge containment. Furthermore, since it is a liquid crystal material, it can be controlled in parallel and can be used for a vertical device.

In the organic transistor, the organic semiconductor material of the present invention is used as a material for an n-channel transistor having a LUMO level of about 3 to 5 eV in combination with a p-channel transistor material having a HOMO level of about 5 to 6 eV. It can be used and is also useful as an n-channel transistor material for realizing a CMOS.

Such a semiconductor device using the organic semiconductor material of the present invention has a layer formed using the organic semiconductor material of the present invention as a semiconductor layer, and a positive electrode and a negative electrode electrically coupled to the semiconductor layer. It is characterized by comprising.

Hereinafter, the present invention will be described more specifically with reference to examples.

In the following Examples, the raw material compounds (Compound I, Compound II and Compound III) were prepared according to the following <Synthesis scheme (Example)>, and then the compound of the present invention (Compound 4) was synthesized. Compound II refers to Compound IIa and Compound IIb, Compound III refers to Compound IIIa and Compound IIIb, and Compound IV refers to Compound IVa and Compound IVb, respectively. In the following Examples, Compound I, Compound II, Compound III, Compound IV and the like are all compounds designated by respective numbers in <Synthesis Scheme (Example)>.

For compound IV (compound IVa and compound IVb), various physical properties relating to the respective “semiconductor properties” were measured.

<Raw material preparation>
Unless otherwise specified, reagents and solvents were purchased from Aldrich Chemical, Tokyo Kasei and Wako Pure Chemicals (unless otherwise specified) and used as they were.

Example 1
(Synthesis of Compound I)
2,6-Dibromo-1,5-diformylnaphthalene, which is a synthetic intermediate (compound I), is described in the literature (Y. Ma, Q. Zheng, Z. Yin, D. Cai, S. Chen, C. Tang. Macromolecules. 2013, 46, 4813). Specifically, it is as follows.

A 10 ml methylene chloride solution containing bromine (3 ml, 9.3 g, 60 mmol) was added dropwise to a 50 ml methylene chloride solution containing 1,5-dimethylnaphthalene (3.9 g, 25 mmol) at room temperature over 1 hour. After 2 hours, the solution was cooled to −20 ° C., the precipitate was filtered off, and recrystallized with ethanol to give 2,6-dibromo-1,5-dimethylnaphthalene (1.49 g, 19%) in white. Obtained as crystals. ¹ HNMR (CDCl ₃ , 400 MHz): 7.75 (d, 2H), 7.64 (d, 2H), 2.77 (s, 6H).

Next, N-bromosuccinimide (6.8 g, 38.2 mmol) and AIBN (0.1 g, 0.64 mmol) were added to a carbon tetrachloride solution of 2,6-dibromo-1,5-dimethylnaphthalene (2 g, 6.35 mmol) under reflux conditions. ) Was added in three portions, and the mixture was further heated under reflux for 12 hours. After cooling, the mixture solution was filtered and washed with methanol and ethyl acetate to obtain 2,6-dibromo-1,5-dibromodimethylnaphthalene as a white powder in 94% yield. ¹ HNMR (CDCl ₃ , 400 MHz): 7.97 (d, 2H), 7.77 (d, 2H), 5.06 (s, 4H).

A mixture of 2,6-dibromo-1,5-dibromodimethylnaphthalene (1.72 g, 3.62 mmol), calcium carbonate (3.62 g, 36.2 mmol) and 1,4-dioxane (75 ml) was heated to reflux for 48 hours. The mixture was filtered while hot, the residue remaining on the filter paper was washed with heated dioxane, the filtrate was concentrated under vacuum, diluted hydrochloric acid (1M, 10 ml) was added, and the precipitate was separated. The obtained precipitate was washed with water and dried to obtain 2,6-dibromo-1,5-dihydroxymethylnaphthalene as a waxy white solid in a yield of 92%. ¹ HNMR (CDCl ₃ , 400 MHz): 8.16 (d, 2H), 7.77 (d, 2H), 5.38 (t, 2H), 5.06 (d, 4H).

Next, to a slurry of 10 g of silica gel and pyridinium chlorochromate (PCC, 8.57 g, 40 mmol) in anhydrous methylene chloride, add 2,6-dibromo-1,5-dihydroxymethylnaphthalene (3.44 g, 10 mmol), Heated to reflux for 4 hours. After cooling, add the same amount of ethyl ether, pass the mixture through 8 cm of silica gel, wash the silica gel with heated chloroform, add the washing liquid, distill off the solvent, recrystallize the residue from chloroform, intermediate The compound 2,6-dibromo-1,5-diformylnaphthalene (compound I represented by the following formula (7)) was obtained in a yield of 74%. ¹ HNMR (CDCl ₃ , 400 MHz): 10.74 (s, 2H), 9.21 (d, 2H), 7.90 (d, 2H).

Example 2
(Synthesis of Compound II)
To a dry triethylemine solution of 2,6-dibromo-1,5-diformylnaphthalene (1 eq.) And 1-tetradecine (2.2 eq.), (Ph ₃ P) ₂ PdCl ₂ (0.1 eq.) And CuI ( 0.1 eq.) Was added and the resulting mixture was heated to 55 ° C. under Ar atmosphere for 4 hours and cooled to room temperature. The produced ammonium salt was removed by filtration, the filtrate was concentrated under reduced pressure, and the resulting residue was purified by silica gel column chromatography (developing solvent: DCM: Hex = 1: 3) to obtain 2,6-ditetra Decynylnaphthalene-1,5-dicarbaldehyde (Compound IIb) was obtained.

In the above, 2,6-didodecynyl-1,5-dicarbaldehyde (Compound IIa) was obtained by using 1-dodecin instead of 1-tetradecine.

(Analysis by ¹ HNMR spectra and high resolution mass spectrometer)
The target compound (Compound II) was subjected to analysis by ¹ HNMR spectrum and a high resolution mass spectrometer under the following conditions.

(Measurement conditions for ¹ HNMR)
Measuring instrument: ¹ HNMR (400 MHz Bruker biospin / AVANCEIII 400A type)
Measurement condition:
・ Measurement frequency: 400MHz
• Solvent for NMR: CDCl ₃

(Measurement conditions for high-resolution mass spectrometry)
Measuring instrument: High-resolution mass spectrum measuring device (HRMS: JEOL JMS-700)
Measurement conditions: As the ionization method, a fast atom bombardment (FAB) method was used.

(Measurement result)
The results of analysis by the above ¹ HNMR spectrum are shown below.
Compound IIa: ¹ HNMR (CDCl ₃ , 400 MHz): 10.97 (s, 2H), 9.47 (d, 2H), 7.70 (d, 2H), 2.56 (t, 4H), 1. 69 (m, 4H), 1.50 (m, 4H), 1.25-1.48 (m, 28H), 0.92 (t, 6H).
Compound IIb: ¹ HNMR (CDCl ₃ , 400 MHz): 10.96 (s, 2H), 9.46 (d, 2H), 7.69 (d, 2H), 2.55 (t, 4H), 1. 68 (m, 4H), 1.49 (m, 4H), 1.24-1.40 (m, 36H), 0.92 (t, 6H).

Example 3
(Synthesis of Compound III)
Compound II dialdehyde (1 eq.) Is dissolved in MeOH / CHCl ₃ (1: 2), BnONH ₂ .HCl (2.4 eq.) And NaOAc (2.4 eq.) Are added, and the resulting mixture is stirred at room temperature. For 5 hours and then filtered using celite (registered trademark). The filtrate was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent: DCM: Hex = 1: 1) to obtain Compound III.

Under the same measurement conditions as in Example 2, Compound III was analyzed using a ¹ H NMR spectrum and a high resolution mass spectrometer. The obtained results are shown below.

Compound IIIa: ¹ HNMR (CDCl ₃ , 400 MHz): 9.01 (s, 2H), 8.79 (d, 2H), 7.52-7.37 (m, 12H), 5.32 (s, 4H) ), 2.52 (t, 4H), 1.69 (t, 4H), 1.52 (t, 4H) 1.27-1.48 (m, 24H), 0.93 (t, 6H).
Compound IIIb: ¹ HNMR (CDCl ₃ , 400 MHz): 8.99 (s, 2H), 8.77 (d, 2H), 7.50-7.35 (m, 12H), 5.30 (s, 4H) ), 2.50 (t, 4H), 1.67 (t, 4H), 1.50 (t, 4H) 1.25-1.40 (m, 32H), 0.90 (t, 6H).

Example 4
(Synthesis of Compound IV)
Compound 4a = 10-IQIQ-10 (compound IVa) and compound 4b = 12-IQIQ-12 (compound IVb) of the present invention were synthesized by the following method.

A dichloroethane solution of compound III (1 eq) obtained in Example 3 was added to a Pyrex (registered trademark) glass flask. AgOTf (0.1 eq) and TfOH (0.1 eq .; 0.10 M in dichloroethane) were added to an inert gas in the dark with respect to a dichloroethane solution of the compound III (1 eq) under stirring by a magnetic stirrer. In an (Ar) atmosphere, the mixture was added and further heated at 75 ° C. for 12 hours under the same stirring. Thereafter, AgOTf / TfOH (0.1 eq) was further added under the same stirring. Furthermore, after heating at 75 ° C. for 12 hours, the completion of the reaction was confirmed by TLC (trade name: silica gel 70F ₂₅₄ manufactured by Wako Pure Chemical Industries, Ltd.).

The reaction mixture obtained above was naturally cooled to room temperature, Et ₃ N was added, the solvent was concentrated, and the residue was purified and isolated by silica column chromatography (developing solvent: dichloroethane). The yield of compound IVa and compound IVb was 70%.

The silica column chromatography conditions used at this time are as follows.
Column size: ID 3.5 cm x length 18 cm
Silica filler: manufactured by Kanto Chemical Co., Ltd., trade name: silica gel 60 100-210 μm

The final products, 10-IQIQ-10 (compound IVa) and 12-IQIQ-12 (compound IVb), were purified by recrystallization from column cherry tomato, and the structure was analyzed by ¹ HNMR (400 MHz Bruker biospin / AVANCEIII 400A). Type) and a high-resolution mass spectrum measurement apparatus (HRMS: JEOL JMS-700). The measurement conditions at this time were the same as in Example 2.

10-IQIQ-10 (Compound IVa):
¹ HNMR (CDCl ₃ , 400 MHz): 10.07 (s, 2H), 8.95 (d, 2H), 7.98 (d, 2H), 7.64 (s, 2H), (d, 2H) , 3.04 (t, 4H), 1.89 (m, 4H), 1.24-1.45 (m, 28H), 0.95 (t, 6H).
HRMS: Calcd. For C36H50N2 [M +]: 510.3974; Found: 510.3974.
12-IQIQ-12 (Compound IVb):
¹ HNMR (CDCl ₃ , 400 MHz): 10.04 (s, 2H), 8.93 (d, 2H), 7.96 (d, 2H), 7.62 (s, 2H), (d, 2H) , 3.02 (t, 4H), 1.87 (m, 4H), 1.31-1.55 (m, 36H), 0.93 (t, 6H).
HRMS: Calcd. For C40H58N2 [M +]: 566.4600; Found: 566.4598.

Example 5
(Suggested thermal analysis of compound IVa, structure by polarizing microscope, X-ray diffraction)
The phase transition behavior of 10-IQIQ-10 (Compound IVa) was measured by suggested thermal analysis (DSC), structural observation with a polarizing microscope, and X-ray diffraction measurement.
<Suggested thermal analysis method>
For the suggested thermal analysis, SHIMAZU DSC-60 manufactured by Shimadzu Corporation was used. For observation of the structure with a polarizing microscope, Optiphot 2-pol manufactured by Nikon, hot stage: manufactured by Mettler: FP900 thermo-system was used, and an observed image was recorded. For X-ray diffraction, Rigaku RAD-2B manufactured by Rigaku Corporation was used to identify phases.

<Suggested thermal analysis conditions>
・ Device: SHIMAZU DSC-60
A sample obtained by weighing 2 mg to 5 mg is put into an aluminum crimp cell as a sample. Then, DSC measurement was performed in a temperature rising process and a temperature falling process of 10 ° C./min using an empty aluminum crimp cell as a reference.

<Conditions for polarizing microscope analysis>
・ Apparatus: Polarizing microscope: Nikon Optiphot 2-pol, Hot stage: Mettler: FP900 thermo-system
A sample sandwiched between two glass substrates was heated to an isotropic phase temperature, and was observed with a polarizing microscope in the cooling process using the above apparatus.
<Conditions for X-ray diffraction>
・ Device: Rigaku RAD-2B manufactured by Rigaku
On the glass substrate, the sample was applied at an isotropic phase temperature, and measurement was performed with the above-described apparatus.

<Result of analysis>
The results obtained by the above analysis are shown in FIGS. According to the DSC chart in FIG. 1, 10-IQIQ-10 (compound IVa) exhibits a plurality of exothermic and endothermic peaks in the temperature lowering and temperature rising processes, respectively, and has a clear phase transition to a liquid crystal phase around 160 ° C. Behavior is seen. Further, according to the polarizing microscope of FIG. 1 and the X-ray diffraction of FIG. 2, a fan-shaped structure characteristic to a low-order liquid crystal phase such as SmA or SmC phase was observed. FIG. 2 is an X-ray diffraction image in the crystal phase.

Example 6
(Suggested thermal analysis of compound 4b, organization by polarizing microscope, X-ray diffraction)
The phase transition behavior of 12-IQIQ-12 (Compound IVb) was measured by suggestive thermal analysis (DSC), structure observation with a polarizing microscope, and X-ray diffraction measurement under the same conditions as in Example 5.

(Computer simulation)
Simulation of liquid crystal molecular length was performed under the following conditions using MOPAC PM7.
-Equipment used: general-purpose personal computer-Software used: The molecular length of each designed molecule is MOPAC 2012. Using MOPAC (Molecular Orbital PACkage), semi-empirical quantum chemical calculation (PM7) by NDDO approximation by Dewar-Thiel was performed and estimated. Regarding the details of such “simulation with MOPAC PM7”, if necessary, documents (JJP Stewart, J. Comp. Chem. 10, 209-264 (1989). JJP Stewart, J. Mol. Modeling 10, 6 -12 (2004). JJP Stewart, J. Phys. Chem. Ref. Data 33, 713-724 (2004). GB Rocha et al J. Comp. Chem. 27, 1101-1111 (2006).) be able to.

<Result of analysis>
In 12-IQIQ-12 (compound IVb), as shown in the DSC chart of FIG. 3, a clear behavior of the phase transition to the liquid crystal phase is observed around 150 ° C. (153.9 to 141.6 ° C.). The presence of a higher-order liquid crystal phase could also be confirmed by structural observation with a polarizing microscope.

FIG. 4 shows X-ray diffraction charts of 12-IQIQ-12 (Compound IVb) at 150 ° C. (upper diagram) and 130 ° C. (lower diagram).

In 12-IQIQ-12 (Compound IVb), as seen in the X-ray diffraction chart of FIG. 4, in the X-ray observation on the low angle side, (001), (002), (003), (004) (005) ) Diffraction peaks from the surface were observed, and it was clearly found that this aggregated phase had a layered structure. In addition, a small diffraction peak observed in a wide angle region was observed.

Referring also to FIG. 5 showing an X-ray diffraction chart at 150 ° C. of 12-IQIQ-12 (compound IVb), which is the same as the upper diagram in FIG. 4, when the interlayer distance is estimated from the diffraction peak of (111) plane, This value is shorter than the molecular length of 38.16 mm of 12-IQIQ-12 (compound IVb) calculated by MOPAC PM7, and the molecule is arranged at an angle of about 42.5 ° with respect to the molecular layer. Turned out to be. The alignment state of the liquid crystal molecules forming the liquid crystal layer is schematically shown on the right side of FIG. From the diffraction peaks on the wide angle side corresponding to (200), (110), and (210), this liquid crystal phase was identified as the SmH phase. Several other peaks in the wide-angle diffraction are difficult to identify and some of these are believed to be due to diffraction from the crystalline domains remaining in the sample. This is because it was difficult to control the temperature of the sample in a narrow temperature range of about 10 ° C. from 140 ° C. to 150 ° C. in X-ray diffraction measurement. From the X-ray diffraction peak at 130 ° C. shown in FIG. 4, the crystal phase was identified in the temperature region of 140 ° C. or lower.

The phase transition temperatures of 10-IQIQ-10 (compound IVa) and 12-IQIQ-12 (compound IVb) determined from DSC analysis are shown in Table 1 below. Table 1 also shows the rearrangement temperature of 14-IQIQ-14 prepared in Example 10. In Table 1, “Iso” represents an isotropic phase, “SmC” and “SmH” represent a smectic C phase and a smectic H phase, and “Cr” represents a crystalline (solid) phase.

Example 7
(Measurement of optical absorption characteristics and ionization potential of compound IVb)
In order to estimate the HOMO and LUIMO levels, 12-IQIQ-12 (Compound IVb) was subjected to measurement of optical absorption characteristics (UV spectrum) and ionization potential (IP) (photoelectron yield spectrum by photoelectron spectroscopy). In these measurements, the following conditions were used.

<UV spectrum measurement>
・ Measurement equipment: Hitachi High-Tech HITACHI U-3900H
A sample dissolved in chloroform was placed in a UV-VIS cell (rectangular cell: optical path length 1 cm), and the measurement was performed using the above measuring instrument.
<Measurement of photoelectron yield spectrum by photoelectron spectroscopy>
Measuring instrument: Photoelectron yield spectrometer PYS-202 manufactured by Sumitomo Heavy Industries, Ltd.
A solution in which the sample is dissolved is drop-cast on a glass substrate with ITO to form a film, and under a vacuum of 1.3 × 10 ⁻² Pa, a Xe light source (HAMAMATSU C9559) and a deuterium light source (USHIO, XB-50101AA) -A) was irradiated with light (3 eV to 9 eV), and the emitted photoelectrons were measured at room temperature using a photoelectron yield spectrometer PYS-202 manufactured by Sumitomo Heavy Industries, Ltd.

(Synthesis of control compound)
In the measurement of the above characteristics, for comparison with 12-IQIQ-12, 12-Chrysene-12 not containing nitrogen was separately described in the literature [M. Kawamura, K. Nishimura, T. Iwakuma, K. Fukuoka, C.I. Hosokawa, M.A. Funahashi, T. Inoue, Y. Jinde, Y. Kawamura, M .; Ito, Y. Tkashima, T. Ogiwara. US. Patent 2010194270, 2010.18].

FIG. 6 shows the UV spectra of the chloroform solutions of 12-Chrysene-12 and 12-IQIQ-12 obtained as described above. In addition, FIG. 7 shows photoelectron yield spectra of 12-Chrysene-12 and 12-IQIQ-12 measured by photoelectron spectroscopy at 25 ° C. The horizontal axis in FIG. 7 is the irradiation photon energy, and the vertical axis is the signal intensity corresponding to the photoelectron yield.

From the results of the above photoelectron spectroscopy measurement, the ionization potentials (IP) of 12-IQIQ-12 and 12-Chrysene-12 were determined to be −6.47 eV and −5.85 eV, respectively. Further, as expected from the aza-acene skeleton, the LUMO level of 12-IQIQ-12 is 0.85 eV lower than 12-Chrysene-12, and the HOMO level is 0.62 eV lower as well. It became clear.

The optical characteristics of 12-IQIQ-12 and 12-Chrysene-12 obtained as described above and various characteristics relating to energy levels are shown in Table 2 below.

Example 8
(Measurement of charge transport properties of compound IVb)
Next, the charge transport property of 12-IQIQ-12 (Compound IVb) was evaluated by the time-of-flight (TOF) method. In this measurement, “12-IQIQ-12” to be measured was purified by repeating column chromatography and recrystallization several times (more than 6 times). The column chromatography conditions and recrystallization conditions used at this time are as follows.

<Column chromatography conditions>
-Column material-Dimensions: Pyrex glass (registered trademark), inner diameter 3.5 cm x length of the part filled with filler 18 cm
Column filler: manufactured by Kanto Chemical Co., Ltd., trade name: silica gel 60 (100-210 μm)
Solvent: dichloromethane <recrystallization conditions>
-Recrystallization solvent: ethanol and chloroform or hexane

The sample purified as described above was injected into a liquid crystal cell having an ITO electrode having a thickness of 9 μm to obtain a sample.

The above measurement was performed by the following method. A cell with a cell thickness of 9 μm (commercially available product: manufactured by EHC), in which two glass substrates with ITO transparent electrodes are bonded together with a thermosetting resin containing a spacer, is heated to the isotropic phase temperature of each compound, and a small amount of sample is prepared. The sample was injected into the cell by contacting the cell opening and utilizing capillary action. The cell was fixed to a sample stage having a heater, and a DC voltage was applied to the electrode. A nitrogen pulse laser with a pulse width of 600 ps was irradiated, and the current flowing at that time was measured with a digital oscilloscope. At that time, the intensity of light irradiation is adjusted so that the integral value (charge amount) of the photocurrent flowing by light irradiation is within 10% of the geometric electric capacity of the cell so as not to cause waveform distortion due to space charge. Noted that.

The results obtained by the measurement are shown in FIG. 8 (a) and 8 (b) show the logarithmically plotted transient photocurrent waveforms measured by the 12-IQIQ-12 TOF method at 164 ° C. and 130 ° C., respectively. Here, FIG. 8A shows the result by the positively charged photocurrent, and FIG. 8B shows the result by the negatively charged photocurrent. The “inset” in each figure shows the respective “linear plot”.

Although it was a dispersive waveform in the SmH phase, as shown in FIG. 8, the running time could be determined by performing a log-log plot. Since this conduction is a high-order liquid crystal phase, it can be considered as electronic conduction instead of ionic conduction. For details of the method for determining such “ion conduction / electronic conduction”, the following documents can be referred to (Documents [19-21]).
・ M. Funahashi, J.A. I. Hanna, Phys. Rev. Lett. 1997, 78, 2184.
・ H. Ahn, A. Ohno, J .; Hanna. Jpn. J. Appl. Phys. 2005, 44, 3764.
・. M. Funahashi, J.A. I. Hanna, Adv. Mater. 2005, 17, 594.

FIG. 9 shows the temperature dependence of the mobility of positive and negative charges at an electric field strength of 6.6 × 10 ⁴ V / cm of 12-IQIQ-12 determined by the above-described measurement of charge transport characteristics. As shown in the temperature range of about 140 to 150 ° C. on the left side of FIG. 11, the mobility of electrons and the mobility of holes in the Sm liquid crystal phase are 1.86 × 10 ⁻⁴ cm ² / Vs and 1.08, respectively. It was estimated to be × 10 ⁻⁴ cm ² / Vs. Although these mobilities have a limited temperature of 10K, the temperature dependence of the mobility was not observed in this region. In addition, no electric field dependency was observed.

On the other hand, as shown in the temperature region of about 155 ° C. or more on the right side of FIG. 9, both negative and positive charge mobilities in the isotropic phase are on the order of 10 ⁻⁵ cm ² / Vs, and a slight electric field dependence It was observed. In the crystalline phase, a significant decrease in photocurrent was observed, suggesting the formation of deep levels due to grain boundaries.

(Example 10)
In the same manner as in Examples 1 to 9, 2.8-ditetradecylisoquino [8,7-h] isoquinoline (14-IQIQ-14) was synthesized, and its physical properties and semiconductor properties were measured. Similar to 10-IQIQ-10 and 12-IQIQ-12, it exhibits a smectic phase around 150 ° C., and its LUMO level is deeper than −3 eV, so this material is effective for electron conduction. Similarly, it can be determined that 10-IQIQ-10 and 14-IQIQ-14 have LUMO levels deeper than -3 eV.

(Summary of Examples 1 to 10)
In conclusion, as described above, 2,8-didecylisoquino is a new rod-like liquid crystal having a low electron density isoquino [8,7-h] isoquinoline (IQIQ) skeleton at the core and an IQIQ derivative expected as an organic semiconductor. [8,7-h] isoquinoline (10-IQIQ-10) and 2.8-didodecylisoquino [8,7-h] isoquinoline (12-IQIQ-12) and 2.8-ditetradecylisoquinolino [8,7-h] isoquinoline (14-IQIQ-14) was synthesized in a relatively high yield using a simple technique.

As shown in FIG. 5, 10-IQIQ-10 and 2.8-ditetradecylisoquinolino [8,7-h] isoquinoline (14-IQIQ-14) are low-order smectic liquid crystals in a limited temperature range. Although 12-IQIQ-12 developed a high-order smectic phase around 140 ° C. to 150 ° C., its LUMO level was −3.33 eV. This material is expected to conduct electrons.

The LUMO level of 10-IQIQ-10 and 2.8-ditetradecylisoquinolino [8,7-h] isoquinoline (14-IQIQ-14) having the same skeleton structure as 12-IQIQ-12 is 12 Similar to -IQIQ-12, it is confirmed to be deeper than -3 eV.

From the measurement of the mobility by the TOF method, the mobility of both electrons and holes was in the order of 10 ⁻⁴ cm ² / Vs in the high-order smectic phase, and was in the order of 10 ⁻⁵ cm ² / Vs in the isotropic phase. This IQIQ material is expected to be applied to organic transistors.

Example 11
In the same manner as in the above example, 2-phenyl-8-decyl-benzothienobenzothiophene (Ph-BTBT-10) was synthesized and the LUMO level was measured and found to be -2.5 eV, and 12-Chrysene-12 The results were as expected by the BTBT skeleton structure, as was the shallow LUMO level of 3 eV or less.

<References>
Regarding detailed conditions such as interpretation, synthesis, experiment, and measurement of terms in the present invention, the following documents can be referred to as necessary.

1. M. Sawamoto, M. J. Kang, E. Miyazaki, H. Sugino, I. Osaka, K. Takimiya. ACS Appl. Mater. Interfaces. 2016, 8, 3810. 2
2. H. Okamoto, S. Hamao, H. Goto, Y. Sakai, M. Izumi, S. Gohda, Y. Kubozono, R. Eguchi. Sci Rep. 2014, 4, 5048.
3. C. Mitsui, T. Okamoto, M. Yamagishi, J. Tsurumi, K. Yoshimoto, K. Nakahara, J. Soeda, Y. Hirose, H. Sato, A. Yamano, T. Uemura, J. Takeya. Adv. Mater. 2014, 26, 4546.
4. K. Nakano, H. Iino, T. Usui, J. Hanna. Appl. Phys. Lett. 2011, 98, 103302.
5. H. Ebata, T. Izawa, E. Miyazaki, K. Takimiya, M. Ikeda, H. Kuwabara, T. Yui. J. Am. Chem. Soc. 2007, 129, 15732.

6. H. Meng, F. Sun, M. B. Goldfinger, G. D. Jaycox, Z. Li, W. J. Marshall, G. S. Blackman. J. Am. Chem. Soc. 2005, 127, 2406.
7. H. Iino, J. Hanna. J. Appl. Phys. 2011, 109, 07505.
8. H. Iino, J. Hanna. Adv. Mater. 2011, 23, 1748.
9. H. Iino, J. Hanna. Jpn. J. Appl. Phys. 2006, 45, 867.
10. H. Iino, T. Usui and J. Hanna, Nat. Commun. 2015, 6, 6828.

11. Y. Lin, D. J. Gundlach, S. F. Nelson, T. N. Jackson. IEEE Trans. Electr. Dev. 1997, 44, 1325.
12. AJJM van Breemen, PT Herwig, CHT Chlon, J. Sweelssen, HFM Schoo, S. Setayesh, WM Hardeman, CA Martin, DM de Leeuw, JJP Valeton, CWM Bastiaansen, DJ Broer, AR Popa-Merticaru, and SCJ Meskers , J. Am. Chem. Soc. 2006, 128, 2336.
13. H. T. Yi, M. M. Payne, J. E. Anthony, V. Podzorov. Nat. Commun. 2012, 3, 1259.
14. S. Tatemichi, M. Ichikawa, T. Koyama, Y. Taniguchi. Appl. Phys. Lett. 2006, 89, 112108.
15. C. Wang, J. Zhang, G. Long, N. Aratani, H. Yamada, Y. Zhao, Q. Zhang. Angew. Chem. Int. Ed. 2015, 54, 6292.

16. G. Gruntz, H. Lee, L. Hirsch, F. Castet, T. Toupance, A. L. Briseno, Y. Nicolas. Adv. Electron. Mater. 2015, 1, 1500072.
17. Y. Ma, Q. Zheng, Z. Yin, D. Cai, S. Chen, C. Tang. Macromolecules. 2013, 46, 4813.
18. M. Kawamura, K. Nishimura, T. Iwakuma, K. Fukuoka, C. Hosokawa, M. Funahashi, T. Inoue, Y. Jinde, Y. Kawamura, M. Ito, Y. Tkashima, T. Ogiwara. US Patent 2010194270, 2010.
19. M. Funahashi, J. I. Hanna, Phys. Rev. Lett. 1997, 78, 2184.
20. H. Ahn, A. Ohno, J. Hanna. Jpn. J. Appl. Phys. 2005, 44, 3764.

21. M. Funahashi, J. I. Hanna, Adv. Mater. 2005, 17, 594.

Claims

A unit A containing a skeleton structure based on isoquinolino-isoquinoline (IQIQ) represented by the following formula (1), an aliphatic chain unit B linked to the unit A by a single bond, and a single bond to the unit A An organic semiconductor material having at least a group containing an aliphatic chain and / or a cyclic structure, or a unit C which is a hydrogen atom; the organic semiconductor material exhibiting liquid crystallinity Semiconductor material.
The unit A has the following formula (2)

Wherein each a is independently a hydrogen atom, a single bond, or a saturated and / or unsaturated cyclic group, the cyclic group being a hydrocarbon group or one or more (It may contain a hetero atom, and at least one a is the cyclic group.)
The unit B and the unit C are each connected to two a by a single bond, and when the a is a single bond, the unit B and / or the unit C is connected to IQIQ. The organic-semiconductor material of Claim 1 couple | bonded with a single bond directly.
A in the formula (2) each independently represents the following structural formula

(In the formula, R is a hydrogen atom or an aliphatic chain group.)
Each of unit B and unit C is bonded to a in such a way as to replace a substitutable site or atom of the above structure, and R in the above formula is a hydrogen atom In some cases, it can be bonded to the unit A by substituting R, or when R is an aliphatic chain group, by substituting a hydrogen atom of the aliphatic chain group of R. Item 3. The organic semiconductor material according to Item 2.
The organic semiconductor material according to any one of claims 1 to 3, wherein the unit B is an aliphatic chain group having 3 to 20 carbon atoms.
The aliphatic chain of unit C is an aliphatic chain group having 3 to 20 carbon atoms, and the group including a cyclic structure of unit C is a group including an aromatic group, a heterocyclic group, or an aliphatic ring group. The organic semiconductor material according to any one of claims 1 to 4, wherein
6. The organic semiconductor material according to claim 1, wherein the LUMO level is deeper than −3 eV.
The organic semiconductor material according to any one of claims 1 to 6, wherein the solubility in toluene is 0.1 wt% or more at room temperature.
The organic semiconductor material according to any one of claims 1 to 7, wherein the mobility of electrons and / or holes is greater than 10 -4 cm 2 / Vs.
The organic semiconductor material according to any one of claims 1 to 8, which exhibits properties of an N-type semiconductor.
The organic semiconductor material according to any one of claims 1 to 9, which exhibits the properties of an N-type semiconductor in at least one of a liquid crystal state and a crystal state.
The organic semiconductor material according to any one of claims 1 to 10, which exhibits a smectic (Sm) liquid crystal phase as a liquid crystal phase to be developed.
A unit A containing a skeleton structure based on isoquinolino-isoquinoline (IQIQ) represented by the following formula (1), an aliphatic chain unit B linked to the unit A by a single bond, and a single bond to the unit A An organic compound having at least a linked group containing an aliphatic chain and / or a cyclic structure, or a unit C which is a hydrogen atom.
The organic compound of Claim 12 represented by following formula (3).

(Wherein a 1 , a 2 , a 3 and a 4 are each independently a hydrogen atom, a single bond, or a saturated and / or unsaturated cyclic group, And / or the unsaturated cyclic group may be a hydrocarbon group or may contain one or more heteroatoms, but at least one of a 1 , a 2 , a 3 and a 4 is a single bond Or a saturated and / or unsaturated cyclic group; at least one of R 1 , R 2 , R 3 and R 4 is each independently an aliphatic chain group, R 1 , R 2 , When any of R 3 and R 4 is not an aliphatic chain group, the remaining R 1 , R 2 , R 3 and R 4 can be hydrogen atoms.)
The aliphatic chain unit B according to claim 12 or the aliphatic chain group according to claim 13 is an aliphatic chain group having 3 to 20 carbon atoms. Organic compounds.
A layer formed using the organic semiconductor material according to any one of claims 1 to 11 or the organic compound according to claims 12 to 14 is provided as a semiconductor layer, and is electrically coupled to the semiconductor layer. A semiconductor device comprising a positive electrode and a negative electrode.