WO2019043451A1

WO2019043451A1 - Compound usable as n-type semiconductor

Info

Publication number: WO2019043451A1
Application number: PCT/IB2018/000977
Authority: WO
Inventors: 若宮淳志; 倉田崇; 今西良樹; 田中光; 萩谷一号
Original assignee: 東洋紡株式会社; 国立大学法人京都大学
Priority date: 2017-08-31
Filing date: 2018-09-03
Publication date: 2019-03-07
Also published as: JP2019043878A; JP6892076B2; WO2019043451A8

Abstract

A compound characterized by comprising at least one of each of a first divalent organic group represented by formula (1), and a second divalent organic group selected from formula (2a) and formula (2b), wherein the first divalent organic group and the second divalent organic group are aligned in an alternating manner.

Description

Compounds that can be used as n-type semiconductors

The present invention relates to a compound that can be used as an n-type semiconductor.

Organic semiconductor materials are one of the most important materials in the organic electronics field, and can be classified into electron donating p-type semiconductor materials and electron accepting n-type semiconductor materials. Various semiconductor devices can be manufactured by appropriately combining p-type semiconductor materials and n-type semiconductor materials, and such devices are, for example, excitons (excitons formed by recombination of electrons and holes). And organic thin film solar cells that convert light into electric power, and organic thin film transistors that control the amount of current and voltage.

Patent Document 1 discloses a p-type organic semiconductor in which the following formula (1x) and the following formulas (c1) to (c31) are combined (in addition, the followings such as T ¹ , T ² , B ¹ , B ² etc. The symbols in the formula (1x) and the symbols in the following formulas (c1) to (c31) such as R ³⁰ to R ⁶⁰ are all based on the definition of Patent Document 1, and the same as in the description of the compounds of the present invention Even when the symbol is used, the meaning of the symbol in the compounds of the present invention follows the contents defined herein).

International Publication No. 2015/122321 brochure

The compound used as the raw material of said Formula (1x) is a compound developed for the first time by the said patent document 1, and it is desirable to raise the versatility and to acquire the merit by a scale-up. For example, if it can be used as a material having characteristics different from those of Patent Document 1, particularly as an n-type semiconductor, it is expected that the versatility of the structure of Formula (1x) will be significantly enhanced. For example, when the application as an acceptor material (n-type semiconductor material) of an organic thin film solar cell is considered, the product “η = open circuit voltage (Voc) of short circuit current density (Jsc), open circuit voltage (Voc), curve factor (FF) It is most desirable that the photoelectric conversion efficiency η calculated by: short circuit current density (Jsc) x curve factor (FF) is high, and in order to achieve this, material development with excellent open circuit voltage (Voc) is desired . As a conventional acceptor material, PCBM (C61) (phenyl C61 -butyric acid methyl ester) is known, and it can be mentioned as a problem that an open circuit voltage (Voc) equivalent to that of the PCBM (C61) can be achieved.

The present invention was made in view of the above circumstances, and an object thereof is to provide a compound suitable for an n-type semiconductor having the above formula (1x) as its partial structure. Another preferred object of the present invention is to provide a compound useful for an n-type semiconductor that expresses a high open circuit voltage (Voc).

The present invention which can achieve the above object is as follows.
[1] One or more of the first divalent organic group represented by the following formula (1) and the second divalent organic group selected from the following formulas (2a) and (2b) And a compound characterized in that the first divalent organic group and the second divalent organic group are alternately arranged.

[In the formula,
T ¹ and T ² are each independently
An alkoxy group;
A thioalkoxy group;
A thiophene ring optionally substituted with a hydrocarbon group or an organosilyl group;
A thiazole ring optionally substituted with a hydrocarbon group or an organosilyl group; or
It represents a phenyl group which may be substituted by a hydrocarbon group, an alkoxy group, a thioalkoxy group, an organosilyl group, a halogen atom or a trifluoromethyl group.
B ¹ and B ^{2 each} represent a thiophene ring which may be substituted by a hydrocarbon group, a thiazole ring which may be substituted by a hydrocarbon group, or an ethynylene group.
R ³¹ to R ³⁴ each independently represent a hydrogen atom, a hydrocarbon group having 6 to 30 carbon atoms, or * -Si (R ⁴⁰ ) ₃ .
R ⁴⁰ represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms, and a plurality of R ^{40 s} may be the same or different.
* In the formulas (2a) and (2b) represents a bond with the organic group of the formula (1), and one end thereof is carbon forming a naphthalene ring which is a partial structure of the formula (2a) or the formula (2b) Bond to an atom. ]
[2] The compound according to [1], wherein each of T ¹ and T ² is a group represented by any one of the following formulas (t1) to (t5).

[In the formulas (t1) to (t5),
R ¹³ to R ¹⁴ each independently represent a hydrocarbon group having 6 to 30 carbon atoms.
R ^15a to R ^16a each independently represent a hydrocarbon group having 6 to 30 carbon atoms, or * -Si (R ¹⁸ ) ₃ .
Each of R ^15b to R ^16b independently represents a hydrogen atom, a hydrocarbon group having a carbon number of 6 to 30, or * -Si (R ¹⁸ ) ₃ .
R ^17a represents a hydrocarbon group having 6 to 30 carbon atoms, * -O-R ¹⁹ , * -S-R ²⁰ , * -Si (R ¹⁸ ) ₃ , a halogen atom, or * -CF ₃ .
R ^17b represents a hydrogen atom, a hydrocarbon group having 6 to 30 carbon atoms, * -O-R ¹⁹ , * -S-R ²⁰ , * -Si (R ¹⁸ ) ₃ , a halogen atom, or * -CF ₃ .
R ¹⁸ represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms, and a plurality of R ^{18 s} may be the same or different.
R ¹⁹ to R ²⁰ each independently represent a hydrocarbon group having 6 to 30 carbon atoms.
* Represents a bond. ]
[3] The compound according to [1] or [2], wherein each of B ¹ and B ² is a group represented by any one of the following formulas (b1) to (b3).

[In the formulas (b1) to (b3), R ^21a , R ^21b and R ²² each independently represent a hydrogen atom or a hydrocarbon group having 6 to 30 carbon atoms. The symbol * represents a bond, and in particular the symbol * on the left represents a bond bonded to the benzene ring of the benzobisthiazole structure. ]
[4] An n-type semiconductor comprising the compound according to any one of [1] to [3].
[5] A solar cell having a photovoltaic part in contact with a donor material and an acceptor material containing a compound according to any one of [1] to [3].

The compound of the present invention is suitable for an n-type semiconductor while having the formula (1) as its partial structure, and in particular shows good characteristics in terms of open circuit voltage (Voc).

1. n-Type Semiconductor Compound The compound of the present invention which can be used as an n-type semiconductor is a first divalent organic group represented by the following formula (1) (hereinafter sometimes referred to as “benzobisthiazole type organic group”) And at least one second divalent organic group (hereinafter sometimes referred to as "perylene / naphthalenediimide type organic group") selected from the following formulas (2a) and (2b), and It is characterized in that the first divalent organic group and the second divalent organic group are alternately arranged.

[In the formula,
T ¹ and T ² are each independently
An alkoxy group;
A thioalkoxy group;
A thiophene ring optionally substituted with a hydrocarbon group or an organosilyl group;
A thiazole ring optionally substituted with a hydrocarbon group or an organosilyl group; or
It represents a phenyl group which may be substituted by a hydrocarbon group, an alkoxy group, a thioalkoxy group, an organosilyl group, a halogen atom or a trifluoromethyl group.
B ¹ and B ^{2 each} represent a thiophene ring which may be substituted by a hydrocarbon group, a thiazole ring which may be substituted by a hydrocarbon group, or an ethynylene group.
R ³¹ to R ³⁴ each independently represent a hydrogen atom, a hydrocarbon group having 6 to 30 carbon atoms, or * -Si (R ⁴⁰ ) ₃ .
R ⁴⁰ represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms, and a plurality of R ^{40 s} may be the same or different.
In the formulas (2a) and (2b), *-represents a bond with the organic group of the formula (1), and one end thereof forms a naphthalene ring which is a partial structure of the formula (2a) or the formula (2b) Bond to a carbon atom. ]

In the present specification, the organosilyl group means a monovalent group in which one or more hydrocarbon groups are substituted on Si atoms, and the number of hydrocarbon groups substituted on Si atoms is two or more. Is preferable, and three are more preferable.
As the benzobisthiazole organic group (formula (1)), one type may be used, or two or more types may be used in combination. The perylene / naphthalenediimide type organic groups (formulas (2a) and (2b)) may be used alone or in combination of two or more.
The benzobisthiazole type organic group and the perylene / naphthalenediimide type organic group each need to be one or more, and when the benzobisthiazole type organic group is represented by A and the perylene / naphthalenediimide type organic group is represented by B, For example, A-B, A-B-A, B-A-B, A-B-A-B, A-B-A-B-A, B-A-B-A-B, etc. It may be a compound, or may be a polymer compound having a larger number of repetitions. The weight average molecular weight (in terms of styrene) of the n-type organic semiconductor is, for example, 10,000 or more, preferably 15,000 or more, and more preferably 20,000 or more. Further, the upper limit is not particularly limited, but when it can be measured, it may be, for example, 1,000,000 or less, or 500,000 or less.
The energy level of LUMO (lowest unoccupied orbital) of the n-type semiconductor compound is, for example, -3.5 eV or less, preferably -4.0 eV or less, more preferably -4.2 eV or less. The lower limit of LUMO can be set as appropriate, and may be, for example, about -4.5 eV.

1.1 Benzobisthiazole Type Organic Group In the benzobisthiazole type organic group represented by the formula (1) constituting the n-type semiconductor compound, T ¹ and T ² may be the same or different from each other However, it is preferable that they are the same from the viewpoint of easy production.
In the benzobisthiazole structural unit represented by the formula (1), T ¹ and T ² are preferably groups represented by the following formulas (t1) to (t5). Specifically, as the alkoxy group of T ¹ and T ² , a group represented by the following formula (t1) is preferable, and as the thioalkoxy group, a group represented by the following formula (t2) is preferable, and hydrocarbon As a thiophene ring which may be substituted by a group or an organosilyl group, a group represented by the following formula (t3) is preferable, and as a thiazole ring which may be substituted by a hydrocarbon group or an organosilyl group, a following formula The group represented by t4) is preferable, and a hydrocarbon group, an alkoxy group, a thioalkoxy group, an organosilyl group, a halogen atom, or a phenyl group which may be substituted with a trifluoromethyl group is a group represented by the following formula (t5) The group represented by) is preferable. When T ¹ and T ² are groups represented by the following formulas (t1) to (t5), light of a short wavelength can be absorbed, and since it has high planarity, efficient π-π stacking Therefore, the photoelectric conversion efficiency can be further enhanced.

[In the formulas (t1) to (t5),
R ¹³ to R ¹⁴ each independently represent a hydrocarbon group having 6 to 30 carbon atoms.
R ^15a to R ^16a each independently represent a hydrocarbon group having 6 to 30 carbon atoms, or * -Si (R ¹⁸ ) ₃ .
Each of R ^15b to R ^16b independently represents a hydrogen atom, a hydrocarbon group having a carbon number of 6 to 30, or * -Si (R ¹⁸ ) ₃ .
R ^17a represents a hydrocarbon group having 6 to 30 carbon atoms, * -O-R ¹⁹ , * -S-R ²⁰ , * -Si (R ¹⁸ ) ₃ , a halogen atom, or * -CF ₃ .
R ^17b represents a hydrogen atom, a hydrocarbon group having 6 to 30 carbon atoms, * -O-R ¹⁹ , * -S-R ²⁰ , * -Si (R ¹⁸ ) ₃ , a halogen atom, or * -CF ₃ .
R ¹⁸ represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms, and a plurality of R ^{18 s} may be the same or different.
R ¹⁹ to R ²⁰ each independently represent a hydrocarbon group having 6 to 30 carbon atoms.
* Represents a bond. ]

In the above formulas (t1) to (t5), a hydrocarbon group having a carbon number of 6 to 30 of R ¹³ , R ¹⁴ , R ^15a , R ^15b , R ^16a , R ^16b , R ^17a , R ^17b , R ¹⁹ , and R ²⁰ Is preferably a branched hydrocarbon group, more preferably a branched saturated hydrocarbon group. The hydrocarbon group of R ¹³ , R ¹⁴ , R ^15a , R ^15b , R ^16a , R ^16b , R ^17a , R ^17b , R ¹⁹ and R ²⁰ has a branch to increase the solubility in an organic solvent Thus, the n-type semiconductor compound of the present invention can obtain appropriate crystallinity. The larger the carbon number of the hydrocarbon group of R ¹³ , R ¹⁴ , R ^15a , R ^15b , R ^16a , R ^16b , R ^17a , R ^17b , R ¹⁹ and R ²⁰ , the better the solubility in organic solvents can be improved However, if it is too large, the reactivity of the perylene / naphthalenediimide type organic group is reduced by the coupling reaction, which makes it difficult to synthesize an n-type semiconductor compound. Therefore, the carbon number of the hydrocarbon group of R ¹³ , R ¹⁴ , R ^15a , R ^15b , R ^16a , R ^16b , R ^17a , R ^17b , R ¹⁹ and R ²⁰ is preferably 8 to 25, and more preferably Is 8 to 20, and more preferably 8 to 16.

^{^{^{^{R 13, R 14, R 15a}}}} , R 15b, R 16a, R 16b, R 17a, the hydrocarbon groups of ^{R 17b,} R ^19, 6 to 30 carbon atoms represented by ^{R 20} is, for example, n- hexyl Alkyl group having 6 carbon atoms such as a group; alkyl group having 7 carbon atoms such as n-heptyl group; n-octyl group, 1-n-butylbutyl group, 1-n-propylpentyl group, 1-ethylhexyl group, 2- Ethylhexyl group, 3-ethylhexyl group, 4-ethylhexyl group, 1-methylheptyl group, 2-methylheptyl group, 6-methylheptyl group, 2,4,4-trimethylpentyl group, 2,5-dimethylhexyl group, etc. N-nonyl group, 1-n-propylhexyl group, 2-n-propylhexyl group, 1-ethylheptyl group, 2-ethylheptyl group, 1-methyl group An alkyl group having 9 carbon atoms, such as octyl group, 2-methyloctyl group, 6-methyloctyl group, 2,3,3,4-tetramethylpentyl group, 3,5,5-trimethylhexyl group; n-decyl group 1-n-pentylpentyl group, 1-n-butylhexyl group, 2-n-butylhexyl group, 1-n-propylheptyl group, 1-ethyloctyl group, 2-ethyloctyl group, 1-methylnonyl group, An alkyl group having 10 carbon atoms such as 2-methylnonyl group and 3,7-dimethyloctyl group; n-undecyl group, 1-n-butylheptyl group, 2-n-butylheptyl group, 1-n-propyloctyl group, An alkyl group having 11 carbon atoms such as 2-n-propyl octyl group, 1-ethyl nonyl group, 2-ethyl nonyl group; n-dodecyl group, 1-n-pentyl heptyl group, 2-n-pentyl group An alkyl group having 12 carbon atoms such as heptyl group, 1-n-butyl octyl group, 2-n-butyl octyl group, 1-n-propyl nonyl group, 2-n-propyl nonyl group; n-tridecyl group, 1- an alkyl group having 13 carbon atoms, such as n-pentyloctyl group, 2-n-pentyloctyl group, 1-n-butyl nonyl group, 2-n-butyl nonyl group, 1-methyldodecyl group, 2-methyldodecyl group; n- Alkyl group having 14 carbon atoms, such as tetradecyl group, 1-n-heptylheptyl group, 1-n-hexyl octyl group, 2-n-hexyl octyl group, 1-n-pentyl nonyl group, 2-n-pentyl nonyl group An alkyl group having 15 carbon atoms such as n-pentadecyl group, 1-n-heptyloctyl group, 1-n-hexylnonyl group, 2-n-hexylnonyl group; n-hexadecyl group; 2- An alkyl group having 16 carbon atoms such as -hexyldecyl group, 1-n-octyloctyl group, 1-n-heptylnonyl group, 2-n-heptylnonyl group; carbon such as n-heptadecyl group or 1-n-octylnonyl group An alkyl group having a carbon number of 18 such as n-octadecyl group, 1-n-nonyl nonyl group; an alkyl group having 19 carbon atoms such as n-nonadecyl group; n-eikosyl group, 2-n-octyldodecyl group An alkyl group having 20 carbon atoms such as a group; an alkyl group having 21 carbon atoms such as an n-heneicosyl group; an alkyl group having 22 carbon atoms such as an n-docosyl group; an alkyl group having 23 carbon atoms such as an n-tricosyl group; -C24 alkyl groups such as tetracosyl group, 2-n-decyl tetradecyl group and the like; and the like. It is preferably an alkyl group having 8 to 20 carbon atoms, more preferably an alkyl group having 8 to 16 carbon atoms, still more preferably a branched alkyl group having 8 to 16 carbon atoms, and particularly preferably 2-ethylhexyl. Group, 3,7-dimethyloctyl group, 2-n-butyloctyl group, 2-n-hexyldecyl group, 2-n-octyldodecyl group, 2-n-decyltetradecyl group. When R ¹³ , R ¹⁴ , R ^15a , R ^15b , R ^16a , R ^16b , R ^17a , R ^17b , R ¹⁹ and R ²⁰ are the groups described above, the n-type semiconductor compound of the present invention can be used as an organic solvent Solubility is improved and it has appropriate crystallinity.

In the groups represented by R ^15a , R ^15b , R ^16a , R ^16b , R ^17a and R ^17b in * -Si (R ¹⁸ ) ₃ in the above formulas (t1) to (t5), aliphatic carbonization of R ¹⁸ The carbon number of the hydrogen group is preferably 1 to 18, and more preferably 1 to 8. Examples of the aliphatic hydrocarbon group of R ¹⁸ include a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, an isobutyl group, an octyl group and an octadecyl group. The carbon number of the aromatic hydrocarbon group of R ¹⁸ is preferably 6 to 8, more preferably 6 to 7, and particularly preferably 6. The aromatic hydrocarbon group R ^18, for example, phenyl group. Among them, as R ¹⁸ , an aliphatic hydrocarbon group is preferable, an aliphatic hydrocarbon group having a branch is more preferable, and an isopropyl group is particularly preferable. The plurality of R ¹⁸ may be the same or different, but are preferably the same. When R ^15a , R ^15b , R ^16a , R ^16b , R ^17a and R ^17b are a group represented by * -Si (R ¹⁸ ) ₃ , the n-type semiconductor compound of the present invention has solubility in an organic solvent improves.

Specific examples of the group represented by * -Si (R ¹⁸ ) ₃ of R ^{15 a} , R ^{15 b} , R ^{16 a} , R ^{16 b} , R ^{17 a} and R ^{17 b in} the above formulas (t1) to (t5) include Trimethylsilyl, ethyldimethylsilyl, isopropyldimethylsilyl, triisopropylsilyl, tert-butyldimethylsilyl, triethylsilyl, triisobutylsilyl, tripropylsilyl, tributylsilyl, dimethylphenylsilyl, methyl diphenyl And alkylsilyl groups such as silyl group; arylsilyl groups such as triphenylsilyl group and tert-butyldiphenylsilyl group; and the like. Among them, an alkylsilyl group is preferable, and a trimethylsilyl group and a triisopropylsilyl group are particularly preferable.

In the above formula (t5), when R ^17a and R ^17b are halogen atoms, any of fluorine, chlorine, bromine and iodine can be used.

T ¹ and T ² may be electron donating or may be electron withdrawing.
Examples of the electron donating T ¹ and T ² include the above (t 1), (t 2) and (t 3), and among (t 5), the group R ^{17 a} is a hydrocarbon group having 6 to 30 carbon atoms, * —O -R ^19, or * also include those which are ^{-S-R 20.} Examples of the electron withdrawing T ¹ and T ² include the above (t 4), and among the (t 5), those in which R ^{17 a} is a halogen atom or * -CF ₃ are also included.

T ¹ and T ² are represented by Formulas (t1), (t3), and (t5) from the viewpoint that the planarity of the entire benzobisthiazole organic group represented by Formula (1) is improved. The group is more preferable, the group represented by the formula (t3) is more preferable, and the groups represented by the following formulas (t3-1) to (t3-16) are particularly preferable. In the formula, * represents a bond.

In the benzobisthiazole organic group represented by the formula (1), B ¹ and B ² may be identical to or different from each other, but from the viewpoint of easy production, they are identical. Is preferred. In the structural unit represented by the formula (1), B ¹ and B ² are each preferably a group represented by any one of the following formulas (b1) to (b3). When B ¹ and B ² are groups represented by the following formulas (b1) to (b3), the planarity of the obtained n-type semiconductor compound is good, and the photoelectric conversion efficiency can be further improved.

[In the formulas (b1) to (b3), R ^21a , R ^21b and R ²² each independently represent a hydrogen atom or a hydrocarbon group having 6 to 30 carbon atoms. The symbol * represents a bond, and in particular the symbol * on the left represents a bond bonded to the benzene ring of the benzobisthiazole structure. ]

^R ^{^21a,} R 21b, examples of the hydrocarbon group having 6 to 30 carbon atoms ^{^{^{^{R 22, R 13, R 14}}}} , R 15a, R 15b, R 16a, R 16b, R 17a, R 17b, R 19, R 20 The group exemplified as the hydrocarbon group having 6 to 30 carbon atoms can be preferably used.
R ^21a , R ^21b and R ^{22 each} may be a hydrogen atom or a hydrocarbon group, and may have 6 to 30 carbon atoms because solubility and crystallinity are improved and photoelectric conversion efficiency may be further enhanced. Are more preferred.

Moreover, in the benzobisthiazole type organic group represented by Formula (1), while it is excellent in planarity as the whole organic group represented by Formula (1), it is a viewpoint which is excellent in planarity also as the whole n-type semiconductor compound obtained. From these, as B ¹ and B ² , groups represented by formulas (b1) and (b2) are more preferable. When B ¹ and B ² are groups represented by the formulas (b1) and (b2), interaction between S atoms and N atoms occurs in the benzobisthiazole type organic group (1) to further improve the planarity Do. Specifically as B ¹ and B ² , groups represented by the following formulas (b1-1) to (b3-1) are preferable. However, in the formula, * represents a bond, and * on the left side bonds to the benzene ring of benzobisthiazole.

Examples of the benzobisthiazole organic group represented by the formula (1) include groups represented by the following formulas (1-1) to (1-48).

1.2 Perylene / Naphthalenediimide Type Organic Group The above benzobisthiazole type organic group (formula (1)) is alternately arranged with perylene / naphthalene diimide type organic groups (formula (2a), (2b)) to obtain n Type semiconductor compounds.
In the formulas (2a) and (2b), examples of the hydrocarbon group having 6 to 30 carbon atoms represented by R ³¹ to R ³⁴ include R ¹³ , R ¹⁴ , R ^15a , R ^15b , R ^16a , R ^16b and R ^17a And groups exemplified as hydrocarbon groups of 6 to 30 carbon atoms, R ^17b , R ¹⁹ and R ²⁰ can be preferably used. R ³¹ and R ³² may be the same as or different from each other, but are preferably the same from the viewpoint of easy production. R ³³ and R ³⁴ may be the same as or different from each other, but are preferably the same from the viewpoint of easy production.
As * -Si (R ⁴⁰ ) ₃ represented by R ³¹ to R ³⁴ , a group exemplified as the above-mentioned * -Si (R ¹⁸ ) ₃ can be preferably used, and as R ^40, it is exemplified as the above R ¹⁸ Groups can be preferably used.
R ³¹ to R ³⁴ may be a hydrogen atom or a hydrocarbon group, and have good solubility and crystallinity, and may further enhance the photoelectric conversion efficiency, and thus have a carbon number of 6 to 30. Groups are more preferred.

The perylene diimide type organic group (2a) has a total of two bonds on the carbon atom constituting the naphthalene ring which is a partial structure of the perylene diimide, and specifically, the sign is given by the following formula Two of carbon a, carbon b, carbon c, carbon d, carbon e, carbon f, carbon g, and carbon h have a bond. The selection of two carbon atoms having a bond is not particularly limited, and a combination of one selected from carbons a to d and one selected from carbons e to f (a line connecting two nitrogen atoms of the perylene diimide structure A combination having one bond on each side); two selected from carbon a to d or two selected from carbon e to h (two on one side of a line connecting two nitrogen atoms in the perylene diimide structure) And any combination of two bonding hands), but in order to ensure appropriate planarity in the molecule, it is a combination of one selected from carbon a to d and one selected from carbon e to f. Preferably there. Such as a combination of one selected from carbon a and b with one selected from carbon g and h (or a combination of one selected from carbon c and d and one selected from carbon e and f) It is preferable that two bonds are present in different naphthalene rings, and such combinations include (i) a combination of carbon c and f, a combination of carbon b and g, (ii) a combination of carbon c and e, carbon b and h , A pair of carbon a and g, a pair of carbon d and f, (iii) a pair of carbon a and h, a pair of carbon d and e, etc., and from the viewpoint of production, (i) carbon c and f A combination of carbon b and g is particularly preferred.

The naphthalene diimide type organic group (2b) also has a total of two bonds on the carbon atom constituting the naphthalene ring which is a partial structure of the naphthalene diimide, and specifically, the sign is given by the following formula Two of carbon i, carbon j, carbon k, and carbon L have a bond. The selection of two carbon atoms having a bond is not particularly limited, and a combination of one selected from carbon i and k and one selected from carbon k and L (a line connecting two nitrogen atoms of a naphthalene diimide structure) Combination that will have one bonding hand on both sides); Combination of carbon i and j or combination of carbon k and L (having two bonding hands on one side of a line connecting two nitrogen atoms of a naphthalene diimide structure In order to secure appropriate planarity in the molecule, it is preferable to use a combination of one selected from carbons i and j and one selected from carbons k and L. Such combinations include (i) a combination of carbon i and k or a combination of carbon j and carbon L, (ii) a combination of carbon i and L or a combination of carbon j and carbon k, from the viewpoint of production ii) A combination of carbon i and L or a combination of carbon j and carbon k is preferred.

Examples of the perylene diimide type organic group represented by the formula (2a) include groups represented by the following formulas (2a-1) to (2a-8).

Examples of the naphthalenediimide organic group represented by the formula (2b) include groups represented by the following formulas (2b-1) to (2b-8).

2. Production Method The n-type semiconductor compound is a benzobisthiazole-type raw material represented by the following formula (4) or formula (5), and a perylene / naphthalene diimide-type raw material represented by the following formula (6) or formula (7) And a coupling reaction.

^{^{^{Wherein, T 1, T 2, B}}} 1, B 2 are identical to those in the formula (1). R ¹ to R ⁴ each independently represent an aliphatic hydrocarbon group having 1 to 6 carbon atoms, a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, or an aryloxy group having 6 to 10 carbon atoms. M ¹ and M ² each independently represent a boron atom or a tin atom. R ¹ and R ² may form a ring with M ¹ , and R ³ and R ⁴ may form a ring with M ² . m and n each represent an integer of 1 or 2; When m and n are 2, plural R ^{1 s} and R ^{3 s} may be the same or different. ]

[Wherein, R ³¹ to R ³⁴ are the same as the aforementioned formulas (2a) and (2b). Y ¹ to Y ⁴ each independently represent a halogen atom, preferably a chlorine atom or a bromine atom, and more preferably a bromine atom.
Each of —Y ¹ and —Y ² in Formula (6) is bonded to a carbon atom forming a naphthalene ring in Formula (6).
Each of —Y ³ and —Y ⁴ in Formula (7) is bonded to a carbon atom forming a naphthalene ring in Formula (7). ]

Note is preferably determined depending on the type of B ^1, B ² or use any of the benzobisthiazole feedstock as formula (4) compound and formula (5) Compound, B ^1, B ² is a hydrocarbon group A thiophene ring (preferably a group represented by the formula (b1)) which may be substituted by or a thiazole ring optionally substituted by a hydrocarbon group (preferably represented by the formula (b2) When it is a group, it is preferable to use a compound of the formula (5), and when B ¹ and B ² are ethynylene groups (preferably, a group represented by the formula (b3)), It is preferred to use a compound.

The details of the coupling reaction can be set as appropriate according to the contents described in WO 2015/122321.
Moreover, a formula (4) compound and a formula (5) compound can be suitably manufactured according to the method as described in an international publication 2015/122321 pamphlet.

Compounds of formula (6) and compounds of formula (7) are disclosed in Chem. Commun. , 2008, 0, 6034-6036, Org. Lett. , 2010, 12, 228-231, Org. Lett. , 2008, 10, 5333-5336, etc. can be suitably produced according to the method described in the like. In addition, 3,4,9,10-perylenetetracarboxylic dianhydride represented by the formula (8) or 1,4,5,8-naphthalenetetracarboxylic dianhydride represented by the formula (9) (these are Halogenated (especially brominated) aromatic rings of Tokyo Chemical Industry Co., Ltd., Sigma-Aldrich Co., etc.), and if necessary purification (recrystallization, column chromatography), etc. The corresponding amine compounds (NH ₂ -R ³¹ , NH ₂ -R ³² , NH ₂ -R ³³ , NH ₂ -R, etc. are produced after dihalo precursors (8x), (9x) etc. are produced by removing the ³⁴ ) (wherein R ³¹ to R ³⁴ are as defined above) can also be produced by imidization. Further, as a raw material represented by the following formula (8) or (9), an amine compound (NH ₂ -R ³¹ , NH ₂ -R ³² , NH ₂ -R ³³ , NH ₂ -R ³⁴ ) (wherein, R ³¹ to R) ³⁴ may be produced by treatment with (as described above) to produce diimidized compounds (8y), (9y) and the like, followed by halogenation (especially bromination).

[Wherein, -Y ¹ to -Y ⁴ and R ³¹ to R ³⁴ are as defined above. ]
Among the compounds of the formula (6), Luminescence Technology Corp. Some are available for purchase. Some of the compounds of formula (7) can be purchased from Tokyo Chemical Industry Co., Ltd.
The molar ratio of the benzobisthiazole type raw material to the perylene / naphthalene diimide type raw material is, for example, in the range of 1:99 to 99: 1, preferably in the range of 20:80 to 80:20, and 40:60. More preferably, it is in the range of ̃60: 40.

3. The compound of the present invention obtained as described above is excellent in acceptor property and is useful as an n-type semiconductor, for example, as an n-type semiconductor material in organic electroluminescence, organic thin film solar cells, organic thin film transistors, etc. The use of is expected. In particular, in an organic thin film solar cell, when the n-type semiconductor compound of the present invention is used as an acceptor material, it exhibits an open voltage (Voc) equivalent to that of a conventional acceptor material PCBM (C61) (phenyl C61 -butyric acid methyl ester), It shows excellent possibilities.

When the n-type semiconductor compound of the present invention is used in an organic solar cell, examples of p-type semiconductors (donor materials) to be combined include poly-3-hexylthiophene (generally called “P3HT”), poly-p-phenylenevinylene, and poly- Alkoxy-p-phenylenevinylene, poly-9,9-dialkylfluorene, poly-p-phenylenevinylene and the like can be mentioned, and a donor-acceptor type semiconductor material is also included. As a donor-acceptor type semiconductor material, for example,
Poly ({4,8-bis [(2-ethylhexyl) oxy] benzo [1,2-b: 4,5-b '] dithiophene-2,6-diyl} {3-fluoro-2-[(2- Ethylhexyl) carbonyl] thieno [3,4-b] thiophenediyl}) (commonly called PTB7), poly [1- (6- {4,8-bis [(2-ethylhexyl) oxy] -6-methylbenzo [1,1] 2-b: 4,5-b ′] dithiophen-2-yl} {3-fluoro-4-methylthieno [3,4-b] thiophen-2-yl} -1-octanone) (generally called PBDTTT-CF) , Poly [(4,8-di (2-ethylhexyloxy) benzo [1,2-b: 4,5-b ′] dithiophene) -2,6-diyl-alt-((5-octylthieno [3,4 -C] pyrrole-4,6-dione) -1,3 Diyl) (aka, PBDTTPD) donor having benzodioxazole thiadiazole-2,6-diyl group, such as - acceptor polymer;
Poly [(4,4'-bis (2-ethylhexyl) dithieno [3,2-b: 2 ', 3'-d] silole) -2,6-diyl-alt- (2,1,3-benzothiadiazole ) -4,7-diyl] (commonly called PSBTBT), poly [N-9 ′ ′-heptadecanyl-2,7-carbazole-alto-5,5- (4 ′, 7′-di-2-thienyl-2] Donor-acceptor type polymers having a 2,1,3-benzothiadiazole-4,7-diyl group such as ', 1', 3'-benzothiadiazole)] (generally called PCDTBT) and the like can be mentioned.

The donor material and the acceptor material (n-type semiconductor) of the present invention become a photovoltaic part of a solar cell by being in contact with each other. The mode of contact can be set as appropriate, and a layer containing a donor material and a layer containing an acceptor material may be stacked, or a mixed layer containing a donor material and an acceptor material may be used.

The present application claims the benefit of priority based on Japanese Patent Application No. 2017-167917 filed on August 31, 2017. The entire content of the specification of Japanese Patent Application No. 2017-167917 filed on August 31, 2017 is incorporated herein by reference.

EXAMPLES Hereinafter, the present invention will be more specifically described by way of examples. However, the present invention is of course not limited by the following examples, and appropriate modifications may be made as long as the present invention can be applied to the purpose. Of course, implementation is also possible, and all of them are included in the technical scope of the present invention.

In addition, each characteristic of the material obtained by the following example was evaluated as follows.
1) Weight average molecular weight (Mw), number average molecular weight (Mn)
The compound to be evaluated is dissolved in a mobile phase solvent (chloroform) to a concentration of 0.5 g / L, gel permeation chromatography (GPC) measurement is performed under the following conditions, and polystyrene is used as a standard sample based on a calibration curve. The number average molecular weight and the weight average molecular weight of the compound to be evaluated were calculated by converting the value. The GPC conditions in the measurement are as follows.
Mobile phase: Chloroform flow rate: 0.6 mL / min
Device: HLC-8320GPC (made by Tosoh Corporation)
Column: TSKgel (registered trademark), SuperHM-H'2 + TSKgel (registered trademark), SuperH 2000 (manufactured by Tosoh Corporation)

2) Ultraviolet-visible absorption spectrum A compound to be evaluated is dissolved in chloroform so as to have a concentration of 0.03 g / L, and an ultraviolet-visible spectroscope (manufactured by Shimadzu Corporation, "UV-2450", "UV-3150"), And ultraviolet visible absorption spectrum measurement was performed using the cell of 1 cm of optical path lengths.

3) Ionization potential (highest occupied molecular orbital (HOMO) energy level)
The target compound to be evaluated was deposited on a glass substrate to a thickness of 50 nm to 100 nm. About this film | membrane, ionization potential (HOMO energy level) was measured by the ultraviolet-ray photoelectric analysis apparatus (The Riken Keiki Co., Ltd. make, "AC-3") under normal temperature normal pressure.

4) Lowest unoccupied orbital (LUMO) energy level The LUMO level is determined from the energy gap (HOMO-LUMO) determined by the peak rising wavelength on the long wavelength side of the UV-visible absorption spectrum and the HOMO energy level determined by the ionization potential The

5) Photoelectric conversion characteristic 1 (donor: P3HT)
Poly (3-hexylthiophene) (P3HT) was used as a donor material and a compound to be evaluated as an acceptor material, and these were dissolved in chlorobenzene so that the total concentration and donor material: acceptor material ratio in the table below could be obtained. Moreover, when 1, 8- diiodo octane was used (it describes in the following table whether to use), it was made to melt | dissolve in the said chlorobenzene so that it might become density | concentration 0.02 mL / mL. The resulting solution was passed through a 0.45 μm filter to form a mixed solution.
A glass substrate on which ITO was formed was subjected to ozone UV treatment to perform surface treatment, and then PEDOT-PSS (poly (3,4-ethylenedioxythiophene) -poly (styrenesulfonic acid)) was applied by a spin coater. . Next, a mixed solution of the above donor material and acceptor material was formed into a film by a spin coater and dried (* 1). Then, an ethanol solution (about 0.3 v%) of tetraisopropyl orthotitanate was spin-coated to prepare a film converted to titanium oxide by moisture in the atmosphere. Thereafter, aluminum as an electrode was vapor deposited to form a device.
Calculate Jsc (short circuit current density), Voc (open circuit voltage), and FF (curve factor) using a solar simulator (CEP 2000, AM 1.5 G filter, radiation intensity 100 mW / cm ² , spectrometer manufactured by the obtained device) The Further, the photoelectric conversion efficiency η was determined based on the following equation.
Photoelectric conversion efficiency η = open circuit voltage (Voc) × short circuit current density (Jsc) × curve factor (FF)
* 1 Drying conditions: When the acceptor material is P-THDT-DBTH-EH-PDI (Example 1) or PCBM (C61) (Comparative Example 1), 110 ° C., 15 minutes. When the acceptor material is P-THDT-DBTH-EH-NDI (Example 2), room temperature, reduced pressure conditions.

6) Photoelectric conversion characteristic 2 (donor: PTB7)
Poly {4, 8-bis [(2-ethylhexyl) oxy) benzo [1,2-b: 4,5-b '] dithiophene-2,6-diyl-lt-alt-3-fluoro-2-[( 2-Ethylhexyl) carbonyl] thieno [3,4-b] thiophene-4,6-diyl} (PTB7) is used as a donor material, and a compound to be evaluated is used as an acceptor material, and the total concentration in the following manner and the donor material are: It was dissolved in chlorobenzene so as to obtain the acceptor material ratio. Moreover, when 1, 8- diiodo octane was used (it describes in the following table whether to use), it was made to melt | dissolve in the said chlorobenzene so that it might become density | concentration 0.02 mL / mL. The resulting solution was passed through a 0.45 μm filter to form a mixed solution.
A glass substrate on which ITO was formed was subjected to ozone UV treatment to perform surface treatment, and then PEDOT-PSS (poly (3,4-ethylenedioxythiophene) -poly (styrenesulfonic acid)) was applied by a spin coater. . Next, a mixed solution of the above donor material and acceptor material was formed into a film by a spin coater and heated at 110 ° C. for 15 minutes. Then, an ethanol solution (about 0.3 v%) of tetraisopropyl orthotitanate was spin-coated to prepare a film converted to titanium oxide by moisture in the atmosphere. Thereafter, aluminum as an electrode was vapor deposited to form a device.
Jsc (short circuit current density), Voc (open circuit voltage), FF (curve factor), photoelectricity using a solar simulator (CEP 2000, AM 1.5 G filter, radiation intensity 100 mW / cm ² , spectrometer manufactured) as the obtained device The conversion efficiency η was determined.

Example 1
P-THDT-DBTH-EH-PDI

In a 20 mL flask, 2,6-bis [5- (2-hexyldecyl) thiophen-2-yl] -4,8-bis (5-trimethylstannylthiophen-2-yl) -benzo [1,2-d 4,5-d ′] bisthiazole (DTH-DBTH-HDTH-DSM, 100 mg, 0.077 mmol) (manufactured according to the method of Example 19 of WO 2015/122321 pamphlet), N N-bis (2-ethylhexyl) -1,7-dibromo-3,4,9,10-perylenediimide (EH-PDI-DB, 60 mg, 0.077 mmol) (purchased from Luminescence Technology Corp.), tris Dibenzylideneacetone) dipalladium (0) -chloroform adduct (Pd ₂ (dba) ₃ · CHCl ₃ ₃ ) (3 mg, 2.9 μmol), tris (2-methoxyphenyl) phosphine (P (2MeO-Ph) ₃ ) (5 mg, 13.1 μmol) and chlorobenzene (Cl-Ph) (8.0 mL) were added to 130 ° C. Reacted for 24 hours. After completion of the reaction, the reaction solution was added to methanol (30 mL), and the precipitated solid was collected by filtration, and the obtained solid was washed by Soxhlet (methanol, acetone, hexane). Next, Soxhlet extraction (chloroform) gave 101 mg (83%) of P-THDT-DBTH-EH-PDI as a black solid.
The molecular weight, ultraviolet-visible spectrum, HOMO energy level, and LUMO energy level of the obtained target compound were examined. The results are shown in Table 1 below.
Further, the results of photoelectric conversion characteristic 1 (donor: P3HT) and photoelectric conversion characteristic 2 (donor: PTB 7) using the obtained target compound are shown in Table 1 below.

Example 2
P-THDT-DBTH-EH-NDI

In a 20 mL flask, 2,6-bis [5- (2-hexyldecyl) thiophen-2-yl] -4,8-bis (5-trimethylstannylthiophen-2-yl) -benzo [1,2-d 4,5-d ′] bisthiazole (DTH-DBTH-HDTH-DSM, 100 mg, 0.077 mmol) (manufactured according to the method of Example 19 of WO 2015/122321 pamphlet), N N-di (2-ethylhexyl) -2,6-dibromo-1,4,5,8-naphthalenediimide (EH-NDI-DB, 50 mg, 0.077 mmol) (purchased from Tokyo Chemical Industry Co., Ltd.), tris (dibenzylideneacetone) dipalladium (0) - chloroform adduct _{_{_{(Pd 2 (dba) 3 ·}}} CHCl 3) (3mg, 2.9μmol), tri (2-methoxyphenyl) phosphine _{(P (2MeO-Ph) 3} ) (5mg, 13.1μmol) and chlorobenzene (Cl-Ph) (8.0 mL) for 24 hours at 130 ° C. added. After completion of the reaction, the reaction solution was added to methanol (30 mL), and the precipitated solid was collected by filtration, and the obtained solid was washed by Soxhlet (methanol, acetone, hexane). Then, Soxhlet extraction (chloroform) gave 93 mg (83%) of P-THDT-DBTH-EH-NDI as a black solid.
The molecular weight, ultraviolet-visible spectrum, HOMO energy level, and LUMO energy level of the obtained target compound were examined. The results are shown in Table 1 below.
The results of photoelectric conversion characteristic 1 (donor: P3HT) using the obtained target compound are shown in Table 1 below.

Comparative Example 1
Photoelectric conversion characteristics 1 were investigated using poly (3-hexylthiophene) (P3HT) as a donor material and PCBM (C61) (phenyl C61-butyric acid methyl ester) as an acceptor material. The results are shown in Table 1 below.

As apparent from the above table, when the acceptor material of the example is used, the obtained photoelectric conversion device exhibits a high Voc (open circuit voltage), indicating that it can be used as an organic thin film solar cell.

The compounds of the present invention can be used as n-type semiconductors. Such compounds include, for example, organic electroluminescence that emits light by the action of excitons (excitons) formed by recombination of electrons and holes, an organic thin film solar cell that converts light into electric power, and the amount of current and voltage. It can be used for controlling organic thin film transistors and the like.

Claims

And one or more of a first divalent organic group represented by the following formula (1) and a second divalent organic group selected from the following formulas (2a) and (2b), and A compound characterized in that a first divalent organic group and a second divalent organic group are alternately arranged.

[In the formula,
T 1 and T 2 are each independently
An alkoxy group;
A thioalkoxy group;
A thiophene ring optionally substituted with a hydrocarbon group or an organosilyl group;
A thiazole ring optionally substituted with a hydrocarbon group or an organosilyl group; or
It represents a phenyl group which may be substituted by a hydrocarbon group, an alkoxy group, a thioalkoxy group, an organosilyl group, a halogen atom or a trifluoromethyl group.
B 1 and B 2 each represent a thiophene ring which may be substituted by a hydrocarbon group, a thiazole ring which may be substituted by a hydrocarbon group, or an ethynylene group.
R 31 to R 34 each independently represent a hydrogen atom, a hydrocarbon group having 6 to 30 carbon atoms, or * -Si (R 40 ) 3 .
R 40 represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms, and a plurality of R 40 s may be the same or different.
In the formulas (2a) and (2b), *-represents a bond with the organic group of the formula (1), and one end thereof forms a naphthalene ring which is a partial structure of the formula (2a) or the formula (2b) Bond to a carbon atom. ]
2. The compound according to claim 1 , wherein T 1 and T 2 are each a group represented by any one of the following formulas (t1) to (t5).

[In the formulas (t1) to (t5),
R 13 to R 14 each independently represent a hydrocarbon group having 6 to 30 carbon atoms.
R 15a to R 16a each independently represent a hydrocarbon group having 6 to 30 carbon atoms, or * -Si (R 18 ) 3 .
Each of R 15b to R 16b independently represents a hydrogen atom, a hydrocarbon group having a carbon number of 6 to 30, or * -Si (R 18 ) 3 .
R 17a represents a hydrocarbon group having 6 to 30 carbon atoms, * -O-R 19 , * -S-R 20 , * -Si (R 18 ) 3 , a halogen atom, or * -CF 3 .
R 17b represents a hydrogen atom, a hydrocarbon group having 6 to 30 carbon atoms, * -O-R 19 , * -S-R 20 , * -Si (R 18 ) 3 , a halogen atom, or * -CF 3 .
R 18 represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms or an aromatic hydrocarbon group having 6 to 10 carbon atoms, and a plurality of R 18 s may be the same or different.
R 19 to R 20 each independently represent a hydrocarbon group having 6 to 30 carbon atoms.
* Represents a bond. ]
3. The compound according to claim 1 , wherein B 1 and B 2 are each a group represented by any one of the following formulas (b1) to (b3).

[In the formulas (b1) to (b3), R 21a , R 21b and R 22 each independently represent a hydrogen atom or a hydrocarbon group having 6 to 30 carbon atoms. The symbol * represents a bond, and in particular the symbol * on the left represents a bond bonded to the benzene ring of the benzobisthiazole structure. ]
An n-type semiconductor comprising the compound according to any one of claims 1 to 3.
A solar cell comprising a photovoltaic part in contact with a donor material and an acceptor material comprising the compound according to any one of claims 1 to 3.