JP2018193418A - Method for producing one-terminal modified polythiophene - Google Patents

Abstract

To provide a method for producing a polythiophene with a selectively sealed one terminal to be a raw material for a block copolymer useful as a self-organization material.SOLUTION: The present invention provides a method for producing a one-terminal modified polythiophene represented by formula (3), including subjecting a compound represented by formula (1) to a reaction with a Grignard reagent RMgX to obtain a polymer, subjecting it to a coupling reaction with trialkyl silyl acetylene in the presence of a coupling catalyst, and then subjecting it to a desilylation reaction (Xand Xindependently represent a halogen atom; Rand Rindependently represent a monovalent organic group that does not change before and after the polymerization reaction, or H, where Rand Rmay not be hydrogen atoms at the same time).SELECTED DRAWING: None

Description

  The present invention relates to a method for producing one-end-modified polythiophene, and more specifically, relates to a method for producing one-end-modified polythiophene that can be suitably used as a raw material for synthesizing a block copolymer that is selectively modified at one end.

In recent years, in the field of materials science, self-assembly of π-conjugated block copolymers has attracted attention in order to control microstructures having novel physical and chemical properties (Non-Patent Documents 1 to 3).
For example, poly (3-hexylthiophene) (P3HT), which is one of π-conjugated polymers, has been studied for applicability to solar cells, field-effect transistors, light-emitting elements, sensors, and the like.
In addition, many types of π, such as block copolymers with polystyrene, block copolymers with poly (2- or 4-vinylpyridine), block copolymers with poly (N-isopropylacrylamide), block copolymers with polyethylene glycol, etc. Block copolymers using conjugated P3HT segments have been designed and synthesized (Non-Patent Documents 5 to 8).

  On the other hand, the cyclization reaction (click reaction) between alkyne and azide catalyzed by copper proceeds under mild and low temperature conditions and is stable to polar groups such as hydroxyl, acid and amino groups. It is useful as a simple method for producing a simple block copolymer (Non-patent Document 9). Moreover, the triazole ring produced by this reaction is characterized by being stable under many special conditions such as high temperature, strong acidity or strong basicity.

A well-controlled terminal alkynyl P3HT is important as a raw material for the production of regular block copolymers to achieve new properties.
Here, in Grignard metathesis polymerization (GRIM) of 2,5-dibromo-3-hexylthiophene, there is an example in which an ethynyl group is introduced at the terminal by excessive use of ethynylmagnesium bromide (Non-patent Document 10).
Although this method yields single-end-capped P3HT with Br-ethynyl ends, this single-end-capped P3HT contains 15% of both-end capped P3HT with ethynyl-ethynyl ends.
Therefore, when the P3HT obtained in the above reaction is subjected to a click reaction, a mixture of diblock copolymer and triblock copolymer is obtained, and these copolymers are very difficult to separate, so that they can be used as self-assembled materials. It was difficult.

Nano Lett. 2010, 10, 2609-2612 J. Mater. Chem. 1996, 6, 1763-1766 Science 1998, 280, 1741-1744 Solar Energy Materials and Solar Cells 2010, 94, 1333-1337 Macromolecules 2008, 41, 7033-7040 Macromolecules 2012, 45, 3070-3077 J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 1785-1794 J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 544-551 J. Am. Chem. Soc. 2005, 127, 210-216 Adv. Mater. 2004, 16, 1017-1019

  The present invention has been made in view of such circumstances, and provides a method for producing a block copolymer useful as a self-organizing material, and a method for producing polythiophene in which one end as a raw material is selectively sealed. The purpose is to do.

  The present inventors synthesized a polythiophene having a halogen atom at one end from a 2,5-dihalothiophene compound having a predetermined substituent at the 3-position and / or 4-position, and then further modified the end of the halogen atom. As a result, it was found that polythiophene having one end selectively sealed was obtained, and it was found that a block copolymer could be efficiently synthesized by using this one-end-modified polythiophene, thereby completing the present invention.

（式中、Ｘ¹およびＸ²は、それぞれ独立にハロゲン原子を表し、Ｒ¹およびＲ²は、それぞれ独立に、重合反応の前後で変化しない１価の有機基または水素原子を表すが、Ｒ¹およびＲ²が同時に水素原子となることはない。）
で表される２，５−ジハロチオフェン化合物を、下記式（２）

（式中、Ｒ³は、炭素数１〜５のアルキル基を表し、Ｘ³は、塩素原子、臭素原子またはヨウ素原子を表す。）で表されるグリニャール試薬と反応させ、続いて重合触媒の存在下で重合させた後、塩酸でクエンチして下記式（３）

（式中、Ｘ²、Ｒ¹およびＲ²は、前記と同じ意味を表し、ｍは、１以上の整数を表し、ｎは、２以上の整数を表す。）
で表される重合体を得、次いで、これをトリアルキルシリルアセチレンと、カップリング触媒の存下でカップリング反応させた後、脱シリル化することを特徴とする、下記式（Ａ）

（式中、Ｒ¹、Ｒ²、ｍおよびｎは、前記と同じ意味を表す。）
で表される片末端修飾ポリチオフェンの製造方法、
２． 前記Ｘ¹が、ヨウ素原子であり、Ｘ²が、臭素原子である１の片末端修飾ポリチオフェンの製造方法、
３． 前記重合反応の前後で変化しない１価の有機基が、炭素数１〜２０の一価炭化水素基である１または２の片末端修飾ポリチオフェンの製造方法、
４． 前記Ｒ¹およびＲ²のいずれか一方が、炭素数１〜１０の直鎖アルキル基であり、他方が、水素原子である１または２の片末端修飾ポリチオフェンの製造方法、
５． 前記Ｒ³が、イソプロピル基である１〜４のいずれかの片末端修飾ポリチオフェンの製造方法、
６． 前記トリアルキルシリルアセチレンが、トリメチルシリルアセチレンである１〜５のいずれかの片末端修飾ポリチオフェンの製造方法、
７． 前記重合触媒が、ニッケル触媒である１〜６のいずれかの片末端修飾ポリチオフェンの製造方法、
８． １〜７のいずれかの製造方法で得られた前記式（Ａ）で表される片末端修飾ポリチオフェンを、下記式（４）

（式中、Ｒ⁴は、炭素数１〜１０のアルキル基または炭素数７〜２０のアラルキル基を表し、ｐは、２以上の整数を表す。）
で表される末端アジド基を有するポリ２−オキサゾリンと反応させる、下記式（Ｂ）

（式中、Ｒ¹、Ｒ²、Ｒ⁴、ｎ、ｍおよびｐは、前記と同じ意味を表す。）
で表されるブロック共重合体の製造方法、
９． 前記式（Ａ）で表される片末端修飾ポリチオフェンと、前記式（４）で表される末端アジド基を有するポリ２−オキサゾリンとの反応によって生じた式（Ｂ）で表されるブロック共重合体を含む反応液を、中性酸化アルミニウムを充填したカラムで濾過する第１の工程と、前記第１の工程で得られた濾液から溶媒を留去して得られた残渣をメタノールに溶かした後、このメタノール溶液中にジエチルエーテルを加えて生じた析出物を濾過する第２の工程と、前記第２の工程で得られた濾過物をテトラヒドロフランに溶かし、この溶液に、ヘキサンを加えて前記式（Ｂ）で表されるブロック共重合体を析出させる第３の工程とを含む８のブロック共重合体の製造方法、
１０． 下記式（Ａ）で表される片末端修飾ポリチオフェン、

（式中、Ｒ¹およびＲ²は、それぞれ独立に、重合反応の前後で変化しない１価の有機基または水素原子を表すが、Ｒ¹およびＲ²が同時に水素原子となることはない。ｍは、１以上の整数を表し、ｎは、２以上の整数を表す。）
１１． 下記式（Ｂ）で表されるブロック共重合体

（式中、Ｒ¹およびＲ²は、それぞれ独立に、重合反応の前後で変化しない１価の有機基または水素原子を表すが、Ｒ¹およびＲ²が同時に水素原子となることはなく、Ｒ⁴は、炭素数１〜１０のアルキル基または炭素数７〜２０のアラルキル基を表し、ｍは、１以上の整数を表し、ｎは、２以上の整数を表し、ｐは、２以上の整数を表す。）
を提供する。 That is, the present invention
1. Following formula (1)

(In the formula, X ¹ and X ² each independently represent a halogen atom, and R ¹ and R ² each independently represent a monovalent organic group or a hydrogen atom that does not change before and after the polymerization reaction. ¹ and R ² are not simultaneously hydrogen atoms.)
A 2,5-dihalothiophene compound represented by the following formula (2)

(Wherein R ³ represents an alkyl group having 1 to 5 carbon atoms, and X ³ represents a chlorine atom, a bromine atom or an iodine atom), followed by reaction of the polymerization catalyst. After polymerization in the presence, the reaction product is quenched with hydrochloric acid and the following formula (3)

(Wherein X ² , R ¹ and R ² represent the same meaning as described above, m represents an integer of 1 or more, and n represents an integer of 2 or more.)
A polymer represented by the following formula (A) is obtained, which is then subjected to a coupling reaction with trialkylsilylacetylene in the presence of a coupling catalyst and then desilylated:

(In the formula, R ¹ , R ² , m and n represent the same meaning as described above.)
A process for producing a single-end modified polythiophene represented by:
2. A process for producing one-end-modified polythiophene of ¹ , wherein X ¹ is an iodine atom and X ² is a bromine atom;
3. A method for producing 1 or 2 one-end-modified polythiophene, wherein the monovalent organic group that does not change before and after the polymerization reaction is a monovalent hydrocarbon group having 1 to 20 carbon atoms;
4). A process for producing 1 or 2 one-terminal-modified polythiophene, wherein either ^one of R ¹ and R ² is a linear alkyl group having 1 to 10 carbon atoms and the other is a hydrogen atom;
5). The method for producing one-end-modified polythiophene according to any one of 1 to 4, wherein R ³ is an isopropyl group,
6). The method for producing one-terminal-modified polythiophene according to any one of 1 to 5, wherein the trialkylsilylacetylene is trimethylsilylacetylene,
7). The method for producing a one-terminal modified polythiophene according to any one of 1 to 6, wherein the polymerization catalyst is a nickel catalyst,
8). One end-modified polythiophene represented by the above formula (A) obtained by the production method of any one of 1 to 7 is represented by the following formula (4):

(In the formula, R ⁴ represents an alkyl group having 1 to 10 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, and p represents an integer of 2 or more.)
It is made to react with the poly 2-oxazoline which has the terminal azide group represented by following formula (B)

(Wherein R ¹ , R ² , R ⁴ , n, m and p have the same meaning as described above.)
A process for producing a block copolymer represented by:
9. Block copolymer represented by the formula (B) generated by the reaction of the one-end modified polythiophene represented by the formula (A) and the poly 2-oxazoline having a terminal azide group represented by the formula (4) The first step of filtering the reaction solution containing the union with a column filled with neutral aluminum oxide, and the residue obtained by distilling off the solvent from the filtrate obtained in the first step was dissolved in methanol. Thereafter, the second step of adding diethyl ether to the methanol solution and filtering the resulting precipitate, and the filtrate obtained in the second step were dissolved in tetrahydrofuran, and hexane was added to the solution to A method for producing a block copolymer of 8, comprising a third step of precipitating the block copolymer represented by the formula (B),
10. One-end modified polythiophene represented by the following formula (A),

(In the formula, R ¹ and R ² each independently represent a monovalent organic group or a hydrogen atom that does not change before and after the polymerization reaction, but R ¹ and R ² do not simultaneously become a hydrogen atom. Represents an integer of 1 or more, and n represents an integer of 2 or more.)
11. Block copolymer represented by the following formula (B)

(In the formula, R ¹ and R ² each independently represents a monovalent organic group or a hydrogen atom that does not change before and after the polymerization reaction, but R ¹ and R ² do not simultaneously become a hydrogen atom, ⁴ represents an alkyl group having 1 to 10 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, m represents an integer of 1 or more, n represents an integer of 2 or more, and p represents an integer of 2 or more. Represents.)
I will provide a.

According to the present invention, poly (3-substituted or 3,4-disubstituted thiophene) (hereinafter also referred to as single-end modified polythiophene or simply polythiophene) in which one end is selectively sealed can be obtained.
By using this one-end modified polythiophene, a block copolymer can be produced efficiently, and the obtained block copolymer is useful as a self-assembling material.

Hereinafter, the present invention will be described in more detail.
In the method for producing a single-end modified polythiophene according to the present invention, a 2,5-dihalothiophene compound represented by the following formula (1) is reacted with a Grignard reagent represented by the following formula (2), followed by polymerization. After polymerization in the presence of a catalyst, the reaction product is quenched with hydrochloric acid to obtain a polymer represented by the following formula (3), which is then subjected to a coupling reaction with trialkylsilylacetylene in the presence of a coupling catalyst. Then, desilylation is performed to obtain a one-end modified polythiophene represented by the following formula (A).

In the above formula (1), X ¹ and X ² each independently represent a halogen atom, and R ¹ and R ² each independently represent a monovalent organic group or a hydrogen atom that does not change before and after the polymerization reaction. (wherein, R ¹ and R ² are not a hydrogen atom at the same time), the formula (2), R ³ represents an alkyl group having 1 to 5 carbon atoms, X ³ is a chlorine atom, a bromine atom or Represents an iodine atom, and in formulas (3) and (A), m represents an integer of 1 or more, and n represents an integer of 2 or more.

Examples of the halogen atom for X ¹ and X ² include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. In consideration of reactivity, a chlorine atom, a bromine atom, and an iodine atom are preferable, and X ¹ represents an iodine atom. X ² is more preferably a chlorine atom or a bromine atom, and more preferably a bromine atom.
The monovalent organic group that does not change before and after the polymerization reaction of R ¹ and R ² is a substituent that is stable with respect to the production method of the present invention, and more specifically, a halogen atom is substituted. A substituent that does not contain an aromatic ring structure, does not have a C═CH ₂ group at the terminal, does not have an ethynyl group at the terminal, and is not a halogen atom.
Examples of the monovalent organic group that does not change before and after the polymerization reaction include carbon numbers such as an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, and an aralkyl group having 7 to 20 carbon atoms. C 1-20 monovalent hydrocarbon group; C 1-20 monovalent carbon such as C 1-20 alkyloxy group, C 6-20 aryloxy group, C 7-20 aralkyloxy group, etc. A hydrogenoxy group; a hydroxy group, a sulfo group, a polyether group, a carboxyl group, a cyano group, a nitro group and the like.

The alkyl group may be linear, branched or cyclic, and specific examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, a linear or branched alkyl group having 1 to 20 carbon atoms such as n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl group; cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclo Examples thereof include cyclic alkyl groups having 3 to 20 carbon atoms such as octyl, cyclononyl, and cyclodecyl groups. Any hydrogen atom of the alkyl group may be substituted with a halogen atom.
Examples of the aryl group include phenyl, 1-naphthyl and 2-naphthyl groups.
Examples of the aralkyl group include benzyl and phenylethyl groups. Any hydrogen atom of the aryl group may be substituted with a substituent that is not a halogen atom, for example, a substituent selected from an alkyl group, an alkoxy group, a hydroxy group, a sulfo group, a cyano group, and a nitro group.
As a polyether group, a terminal is a hydroxyl group, a C1-C10 alkoxy group, or a phenoxy group, and the bond with thiophene should just be an oxygen atom. More specifically, it is represented by a —O — ((CH ₂ ) _r O) _q —R ⁵ group, r is 2 or 3, and all are the same within the same substituent, and the terminal substituent R ⁵ is hydrogen. Examples of the substituent include an atom, an alkyl group having 1 to 10 carbon atoms, and a phenyl group, and having a total carbon number of 2 to 20.
Among these, as R ¹ and R ² , one is a hydrogen atom, the other is an alkyl group or polyether group having 1 to 10 carbon atoms, both are alkyl groups having 1 to 10 carbon atoms, and both are polyether groups. Preferably, one is a hydrogen atom and the other is more preferably a linear alkyl group having 1 to 10 carbon atoms, and R ² is a hydrogen atom and R ¹ is more preferably a linear alkyl group having 1 to 8 carbon atoms.

Examples of the alkyl group having 1 to 5 carbon atoms of R ³ include those having 1 to 5 carbon atoms among the alkyl groups exemplified in the above R ¹ , among which alkyl groups having 1 to 3 carbon atoms are preferable, An isopropyl group is more preferable.
X ³ is preferably a chlorine atom or a bromine atom.
If m is an integer of 1 or more and n is an integer of 2 or more, there is no particular limitation, but considering the number average molecular weight of the polymer described later, n is preferably 2 to 1,000, more preferably 10 to 500. .
Further, m + n is preferably from 3 to 1,000, and more preferably from 10 to 500.

[1] Polymerization of 2,5-dihalothiophene compound represented by formula (1) The polymerization reaction conditions for the 2,5-dihalothiophene compound represented by formula (1) are based on Grignard metathesis reaction of McCullough. In accordance with the conventional polythiophene synthesis method.
Specifically, the 2,5-dihalothiophene compound represented by the above formula (1) is reacted with a Grignard reagent represented by the formula (2) in the solvent, that is, an organomagnesium halogen compound, to obtain the above formula. After preparing an organomagnesium halogen compound of the 2,5-dihalothiophene compound represented by (1), a polymerization catalyst is added and polymerized.

Specific examples of the organomagnesium halogen compound represented by the formula (2) include methylmagnesium chloride, methylmagnesium bromide, ethylmagnesium chloride, ethylmagnesium bromide, i-propylmagnesium chloride, i-propylmagnesium bromide, t-butylmagnesium. Although C1-C5 alkyl magnesium halides, such as a chloride and t-butyl magnesium bromide, are mentioned, Especially, i-propyl magnesium chloride and i-propyl magnesium bromide are preferable.
The amount of the organomagnesium halogen compound used is not particularly limited, but is preferably in the range of 0.8 to 2 moles per mole of the 2,5-dihalothiophene compound as a substrate, and the subsequent polymerization reaction In view of the selectivity and reaction efficiency, the range of 0.9 to 1.5 mol times is more preferable, and the range of 0.95 to 1.0 mol times is even more preferable.

  The solvent used in the Grignard metathesis reaction is not particularly limited as long as it does not adversely affect the reaction. For example, saturated aliphatic hydrocarbons such as pentane, hexane, heptane, octane, nonane, decane, and cyclohexane; benzene , Aromatic hydrocarbons such as toluene, ethylbenzene, propylbenzene, o-xylene, m-xylene, p-xylene, o-ethyltoluene, m-ethyltoluene, p-ethyltoluene; dimethyl ether, ethylmethyl ether, diethyl ether , Dipropyl ether, butyl methyl ether, t-butyl methyl ether, dibutyl ether, cyclopentyl methyl ether, diphenyl ether, tetrahydrofuran (THF), 2-methyltetrahydrofuran, 1,4-dioxane, etc. Such as Le acids and the like. These may be used alone or in combination of two or more. Of these, tetrahydrofuran, 2-methyltetrahydrofuran, and 1,4-dioxane are preferable.

The temperature of the Grignard metathesis reaction is not particularly limited, but is preferably about −20 to 50 ° C., preferably about −10 to 30 ° C., and −5 to 10 ° C. in consideration of suppressing side reactions. The degree is more preferable.
The organomagnesium halogen compound of the 2,5-dihalothiophene compound, which is an intermediate obtained by the Grignard metathesis reaction, is preferably used in the polymerization reaction as it is without purification from the viewpoint of simplifying the reaction operation. It is more preferable to carry out a polymerization reaction.

As the polymerization catalyst used in the present invention, for example, RD McCullough, Adv. Mater., 1998, 10 (2), 93-116 and the referential selective polymerization as listed in the cited references are suitably used. A palladium catalyst or a nickel catalyst can be used, and specific examples thereof include bis (triphenylphosphino) palladium dichloride (Pd (PPh ₃ ) Cl ₂ ), palladium (II) acetate (Pd (OAc) ₂ ), tetrakis (Triphenylphosphine) palladium (Pd (PPh ₃ ) ₄ ), tetrakis (triphenylphosphine) nickel (Ni (PPh ₃ ) ₄ ), nickel (II) acetylacetonate (Ni (acac) ₂ ), dichloro (2, 2'-bipyridine) nickel, and dibromobis (triphenylphosphine) nickel _{(Ni (PPh 3) 2 Br} 2), the ligand-containing two Kel and palladium catalysts such as tri-t-butylphosphine, triadamantylphosphine, 1,3-bis (2,4,6-trimethylphenyl) imidazolidinium chloride, 1,3-bis (2,6-diisopropylphenyl) Examples thereof include nickel and palladium catalysts containing imidazolidinium chloride or 1,3-diadamantylimidazolidinium chloride, with nickel catalysts being preferred, in particular bis (diphenylphosphino) propane nickel dichloride (Ni (dpppp) Cl. _2), bis (diphenylphosphino) ethane nickel dichloride (Ni (dppe) Cl ₂₎ is more preferable.
Palladium and nickel catalysts comprising a combination of the ligands described above can be used as well.

  The amount of the polymerization catalyst used is not particularly limited, but is typically 0.1 to 20 mol%, preferably 10 to 20 mol%, based on the amount of the 2,5-dihalothiophene compound. More preferably, it is the range of 10-15 mol%.

  The 2,5-dihalothiophene compound represented by the above formula (1), the Grignard reagent and the polymerization catalyst represented by the formula (2) were prepared by a conventionally known method even when using commercially available products. May be used.

The organic solvent used in the polymerization reaction is not particularly limited as long as it does not react with the organometallic compound and does not adversely affect the polymerization reaction. For example, pentane, hexane, cyclohexane, heptane, etc. Aliphatic hydrocarbons; aromatic hydrocarbons such as benzene, toluene and xylene; and ethers such as diethyl ether, t-butyl methyl ether, dibutyl ether, amyl ether, 1,4-dioxane and THF These may be used alone or in combination of two or more such as a mixed solvent of THF and toluene.
Among these, ethers are preferable in the present invention, and THF is more preferable.

The temperature of the polymerization reaction is not particularly limited, and about −10 to 200 ° C. can be adopted. However, the temperature during polymerization is preferably about 10 to 100 ° C., more preferably about 20 to 50 ° C. Moreover, about -10-20 degreeC is preferable and the temperature at the time of a polymerization catalyst addition has more preferable about -5-10 degreeC.
The pressure during the polymerization reaction is not particularly limited, and can be performed in the atmosphere.

After the polymerization reaction, a polymer having a halogen atom at the terminal represented by the above formula (3) is obtained by quenching with hydrochloric acid.
In this case, the concentration of hydrochloric acid is not particularly limited, and is about 1 to 12M, preferably about 3 to 10M, and more preferably about 4 to 7M.
After quenching with hydrochloric acid, a pure polymer represented by the formula (3) can be obtained by post-treatment and purification according to a conventional method.

  In the above polymerization reaction, a metal complex of a thiophene dimer represented by the following formula is generated at the start of polymerization and the reaction proceeds.

（式中、Ｒ¹、Ｒ²およびＸ²は上記と同じ意味を表し、Ｍは、触媒金属を、Ｌはリガンドを表す。）

(Wherein R ¹ , R ² and X ² represent the same meaning as described above, M represents a catalyst metal, and L represents a ligand.)

  Accordingly, the molecular chain terminal or molecular chain of the obtained polymer always contains the structure derived from the dimer, and when it is included at the terminal, the resulting polymer has the formula (3-1) When the polymer is contained in the main chain, the resulting polymer has the structure of formula (3-2). In the present invention, these are collectively represented by the above formula (3).

（式中、Ｒ¹、Ｒ²およびＸ²は上記と同じ意味を表す。）

(Wherein R ¹ , R ² and X ² represent the same meaning as described above.)

[2] Synthesis of single-end modified polythiophene represented by formula (A) The polythiophene represented by formula (A) is based on a halogen atom remaining at the end of the polymer represented by formula (3), It can be obtained by desilylation after conducting a coupling reaction such as Sonogashira reaction with trialkylsilylacetylene in the presence of a coupling catalyst.
Specific examples of the trialkylsilylacetylene include trimethylsilylacetylene, triethylsilylacetylene, triisopropylsilylacetylene and the like, and trimethylsilylacetylene is preferable.

As the coupling catalyst, a metal complex catalyst is usually used.
Examples of the metal complex include a palladium complex and a nickel complex, but a palladium complex is preferable, and depending on the reaction, a copper catalyst is preferably used as a co-catalyst.
As the metal complex catalyst, those having various structures can be used, but it is preferable to use a so-called low-valent metal complex, particularly a zero-valent metal having a tertiary phosphine or tertiary phosphite as a ligand. Complex catalysts are preferred.
In addition, a suitable precursor that can be easily converted into a zero-valent metal complex catalyst in the reaction system can be used, and further, a metal that does not contain tertiary phosphine or tertiary phosphite as a ligand in the reaction system. A complex and a tertiary phosphine or tertiary phosphite which is a ligand can be mixed to produce a low-valent metal complex catalyst having tertiary phosphine or tertiary phosphite as a ligand.

  Specific examples of the tertiary phosphine or tertiary phosphite as the ligand include triphenylphosphine, tri-o-tolylphosphine, diphenylmethylphosphine, phenyldimethylphosphine, 1,2-bis (diphenylphosphino) ethane, 1,3-bis (diphenylphosphino) propane, 1,4-bis (diphenylphosphino) butane, 1,1′-bis (diphenylphosphino) ferrocene, trimethyl phosphite, triethyl phosphite, triphenyl phosphite, etc. These ligands may be used alone or in combination of two or more.

Specific examples of a palladium complex containing tertiary phosphine or tertiary phosphite as a ligand include (ethylene) bis (triphenylphosphine) palladium, tetrakis (triphenylphosphine) palladium, bis (triphenylphosphine) dichloropalladium, etc. Is mentioned.
In addition, as a metal complex catalyst, a palladium complex not containing tertiary phosphine or tertiary phosphite and a palladium complex containing tertiary phosphine or tertiary phosphite as a ligand can be used in combination. You may further combine the said ligand.
Specific examples of the palladium complex containing no tertiary phosphine or tertiary phosphite include bis (benzylideneacetone) palladium, tris (benzylideneacetone) dipalladium, bis (acetonitrile) dichloropalladium, bis (benzonitrile) dichloropalladium, acetic acid. Palladium, palladium chloride, palladium-activated carbon, etc. are mentioned.

The amount of the coupling catalyst used may be a so-called catalytic amount, preferably 20 mol% or less, more preferably 10 mol% or less with respect to the polymer represented by the formula (3) as the raw material.
The copper catalyst as the co-catalyst is preferably monovalent, and specific examples thereof include copper (I) chloride, copper (I) bromide, copper (I) iodide, copper (I) acetate and the like. It is done.
Although the usage-amount of a promoter is not specifically limited, 10 mol% or less is preferable with respect to the polymer represented by the formula (A) which is a raw material, and 5 mol% or less is more preferable.

In the above coupling reaction, a base can also be used. Specific examples thereof include sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium hydrogen carbonate, potassium hydrogen carbonate, potassium phosphate, sodium carbonate, potassium carbonate, carbonic acid. Inorganic bases such as lithium and cesium carbonate; methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, propylamine, dipropylamine, tripropylamine, isopropylamine, diisopropylamine, triisopropylamine, butylamine, dibutylamine, tri Amines such as butylamine, diisopropylethylamine, pyridine, imidazole, quinoline, collidine, pyrrolidine, piperidine, morpholine, N-methylmorpholine; Arm, potassium acetate, lithium acetate, and the like.
When the base is used, the amount used is not particularly limited, but is preferably about 1 to 10 moles per mole of the polymer represented by the formula (3) as the raw material.

The reaction solvent is not particularly limited as long as it is stable under the reaction conditions and does not adversely influence the reaction. For example, water; alcohols such as methanol and ethanol; amines such as triethylamine Aprotic polar organic solvents such as dimethylformamide, dimethyl sulfoxide, dimethylacetamide, N-methylpyrrolidone; ethers such as diethyl ether, diisopropyl ether, methyl t-butyl ether, cyclopentyl methyl ether, THF, 1,4-dioxane; Aliphatic hydrocarbons such as pentane, hexane, heptane, petroleum ether, aromatic hydrocarbons such as benzene, toluene, xylene, mesitylene, chlorobenzene, dichlorobenzene, nitrobenzene, tetralin, chloroform, dichloromethane Carbon tetrachloride, halogenated hydrocarbons dichloroethane, methyl acetate, ethyl acetate, butyl acetate, lower fatty acid esters of methyl propionate, acetonitrile, propionitrile, etc. nitriles such as butyronitrile may be used. These solvents can be appropriately selected in consideration of the ease of reaction and the like, and may be used singly or in combination of two or more.
In addition, the said solvent can also be used as a solvent which does not contain water using a suitable dehydrating agent and a desiccant.

Although reaction temperature can employ | adopt from the boiling point of the reaction solvent to be used to -100 degreeC, -50-200 degreeC is preferable and 20-150 degreeC is more preferable.
The reaction time is usually about 0.1 to 1,000 hours, but preferably 0.5 to 100 hours.
After completion of the reaction, a polymer having a trialkylsilylethynyl group at the terminal can be obtained by post-treatment according to a conventional method and purification as necessary.
After the obtained polymer having a trialkylsilylethynyl group is treated with a desilylating agent such as tetrabutylammonium fluoride (TBAF), it is post-treated according to a conventional method to obtain the target formula (A). The one-terminal modified polythiophene represented is obtained.

  The molecular weight of the one-end modified polythiophene obtained in the present invention is not particularly limited, but the number average molecular weight is preferably about 1,000 to 500,000, preferably about 3,000 to 100,000, 000 to 50,000 is more preferable. The number average molecular weight is a polystyrene equivalent value by GPC.

[3] Click reaction Since the one-end modified polythiophene represented by the formula (A) obtained above has an ethynyl group only at one end, the polythiophene is represented by the following formula (4). A block copolymer can be efficiently produced by reacting with poly (2-ethyl-2-oxazoline) having an azide group at the terminal.

R ⁴ represents an alkyl group having 1 to 10 carbon atoms or an aralkyl group having 7 to 20 carbon atoms. Examples of the alkyl group include the same groups as described above. Examples of the aralkyl group include benzyl group, phenylethyl A benzyl group is preferred.
p represents an integer of 2 or more, preferably 2 to 1,000, and more preferably 10 to 500.

As the conditions for the click reaction, known conditions can be employed. For example, the above polymers can be used in the presence of a copper catalyst such as CuI and a base such as diisopropylamine at about 0 to 100 ° C. for 0.1 to 500 hours. A method of reacting to some extent can be adopted.
The reaction ratio of each of the above polymers is arbitrary, and can be set as appropriate according to the desired block copolymer.

After the reaction is completed, it is preferable to combine a plurality of purifications in order to efficiently remove the solid copper catalyst and the unreacted polymer.
For example, after filtering through a column filled with neutral aluminum oxide to remove the solid catalyst, the residue obtained by distilling off the solvent from the filtrate was dissolved in methanol and unreacted poly (2-ethyl). 2-oxazoline) was removed, and diethyl ether was added to the methanol solution to precipitate the block copolymer and unreacted one-end-modified polythiophene. After filtration, the filtrate was dissolved in THF. Pure block copolymer can be obtained by adding hexane to precipitate the block copolymer.

The poly (2-ethyl-2-oxazoline) having an azide group at the terminal used for the click reaction can be produced by a known method.
For example, 2-ethyl-2-oxazoline is polymerized using benzyl bromide as a polymerization initiator, and then reacted with sodium azide added to the reaction solution, whereby the terminal represented by the above formula (4) is obtained. Thus, poly (2-ethyl-2-oxazoline) having an azide group is obtained.

Hereinafter, although a synthesis example, an Example, and a comparative example are given and this invention is demonstrated more concretely, this invention is not limited to the following Example. In addition, each measuring apparatus used in the Example is as follows.
[GPC]
Device: Shodex GPC-101 (manufactured by Showa Denko KK)
Column: 2 Shodex KF-804L (manufactured by Showa Denko KK)
Column temperature: 40 ° C
Solvent: Chloroform 1 mL / min Detector: UV (254 nm), RI
Calibration curve: Standard polystyrene [ ¹ H-NMR]
Equipment: JEOL ECA-500 and ECA-600
[TG-DTA]
Equipment: Seiko Instruments Inc. TG / DTA 6200
[MALDI-TOFF]
Equipment: AXIMA-CFR plus Shimadzu / Kratos
Reflection ion mode: Laser (λ = 337nm)
Matrix: 1,8-dihydroxy-9 [10H] -anthracenone

（式中、ｐは上記と同じ意味を表す。） [Synthesis Example 1] Synthesis of PEtOx

(Wherein p represents the same meaning as described above.)

The well-sealed pressure-resistant sealed tube was heated under reduced pressure, cooled to room temperature, and then replaced with argon. A solution of benzyl bromide (0.1 mL, 0.8 mmol) and 2-ethyl-2-oxazoline (2 mL, 20 mmol) in dry dimethylacetamide (5.0 mL) was added to the solution at 100 ° C. under an argon atmosphere. Stir for 12 hours. After allowing to cool to room temperature, sodium azide (737.8 mg, 10 mmol) was added and stirred at 80 ° C. for 12 hours. The reaction was quenched with water and extracted with dichloromethane. The organic layer was washed with aqueous sodium hydrogen carbonate solution, dried over anhydrous MgSO ₄ and concentrated under reduced pressure. Diethyl ether was added to the residue, and the insoluble matter was collected by suction filtration and washed with diethyl ether to obtain PEtOx (20.3 g, yield 98.2%).
¹ H NMR (600 MHz, CDCl ₃ ) δ 3.33-3.46 (b, 4H), 2.26-2.40 (b, 2H), 1.08-1.11 (b, 3H).
GPC (eluent: chloroform, polystyrene standard): RI signal, Mn = 3,700, Mw / Mn = 1.06.

（式中、ｍ、ｎは、上記と同じ意味を表す。） [Example 1] Synthesis of P3HT _P (1) Synthesis of P3HT _B

(In the formula, m and n represent the same meaning as described above.)

2-Bromo-3-n-hexyl-5-iodothiophene (943.2 mg, 2.53 mmol) dissolved in 20 mL of dry THF was added under argon atmosphere to a 200 mL eggplant flask equipped with a three-way cock and purged with argon. Added at 0 ° C. To this was added isopropylmagnesium chloride (2.0 M THF solution, 1.23 mL, 2.45 mmol) with a syringe, and the mixture was stirred at 0 ° C. for 2 hours. A solution obtained by suspending Ni (dppp) Cl ₂ (34.3 mg, 0.063 mmol) in dry THF (10 mL) was added to the reaction solution at 0 ° C., followed by stirring at room temperature for 2 hours. 5M Hydrochloric acid was added to the reaction mixture, and the mixture was extracted with chloroform. The organic layer was washed with water, dried over anhydrous MgSO ₄ and concentrated under reduced pressure. Methanol was added to the residue, and the insoluble matter was collected by suction filtration and washed with methanol to obtain pure P3HT _B (331 mg, yield 78.5%).
¹ H NMR (600 MHz, CDCl ₃ ) δ 6.98 (s, 1H), 2.81 (t, 2H), 1.71 (quint, 2H), 1.44-1.30 (m, 6H), 0.91 (t, 3H).
GPC (eluent: chloroform, polystyrene standard): RI signal, Mn = 10,200, Mw / Mn = 1.04. UV signal, Mn = 9,190, Mn / Mw = 1.10.

（式中、ｍ、ｎは、上記と同じ意味を表す。） (2) Synthesis of P3HT _S

(In the formula, m and n represent the same meaning as described above.)

In a well-dried 200 mL eggplant flask, P3HT _B (331 mg, 0.036 mmol), Pd (PPh ₃ ) ₂ Cl ₂ (4.74 mg, 6.76 μmol), CuI (0. 7 mg, 3.75 μmol), trimethylsilylacetylene (0.022 mL, 0.157 mmol) and diisopropylamine (20 mL) were added, and the freeze degassing cycle was repeated three times. The reaction mixture was stirred at 60 ° C. overnight. The reaction was cooled to room temperature, quenched with 1M dilute hydrochloric acid, and extracted with chloroform. The organic layer was washed with water, dried over anhydrous MgSO ₄ and concentrated under reduced pressure. Methanol was added to the residue, and insoluble matter was collected by suction filtration and washed with methanol to obtain pure P3HT _S (319 mg, yield 96.4%).
¹ H NMR (600 MHz, CDCl ₃ ) δ 6.98 (s, 1H), 2.81 (t, 2H), 1.71 (quint, 2H), 1.44-1.30 (m, 6H), 0.91 (t, 3H), 0.27 ( s, 0.21H).
GPC (eluent: chloroform, polystyrene standard): RI signal, Mn = 9,340, Mw / Mn = 1.09. UV signal, Mn = 8,710, Mn / Mw = 1.14.

（式中、ｍ、ｎは、上記と同じ意味を表す。） (3) Synthesis of P3HT _P

(In the formula, m and n represent the same meaning as described above.)

P3HT _S (105 mg) dissolved in 20 mL of dry THF was added to a well-dried 200 mL eggplant flask, and fluorinated tetrabutylammonium (1 mL, 23 mg / mL in a mixed solvent of water and THF) was added at 0 ° C. under a nitrogen atmosphere. Added and stirred for 30 minutes. The reaction solution was poured into a large amount of methanol, and insoluble matter was collected by suction filtration and washed with methanol to obtain P3HT _P (100 mg, yield 95.2%).
¹ H NMR (600 MHz, CDCl ₃ ) δ 6.98 (s, 1H), 3.53 (s, 0.01H), 2.81 (t, 2H), 1.71 (quint, 2H), 1.44-1.30 (m, 6H), 0.92 (t, 3H).
GPC (eluent: chloroform, polystyrene standard): RI signal, Mn = 8,450, Mw / Mn = 1.14. UV signal, Mn = 8,670, Mn / Mw = 1.12.

（式中、ｍ、ｎ、ｐは、上記と同じ意味を表す。） Example 2 Synthesis of P3HT-b-PEtOx

(In the formula, m, n and p have the same meaning as described above.)

A round bottom flask equipped with a three-way cock was heated under reduced pressure and then cooled to room temperature under an argon atmosphere. Into this, P3HT _P (9.83 μmol), PEtOx (49.3 μmol), CuI (37 mg, 0.196 mmol), and diisopropylamine (0.17 mL, 0.983 mmol) were added under an argon atmosphere, and then dried. THF (20 mL) was added via syringe. The resulting mixture was lyophilized and degassed three times and then stirred at 60 ° C. for 48 hours.
After completion of the reaction, the mixture was filtered through a column filled with neutral aluminum oxide to remove Cu as a solid catalyst, the filtrate was collected, and the solvent was distilled off under reduced pressure. Subsequently, the obtained solid polymer was dissolved in methanol (100 mL) to remove unreacted PEtOx, and then diethyl ether was slowly added to the methanol solution until the block copolymer and unreacted P3HT _P were precipitated. It was. After filtration, the precipitated polymer was collected with THF, and hexane was slowly added to 200 mL of this polymer in THF until the block copolymer was precipitated. The final precipitate was collected in THF to obtain pure P3HT-b-PEtOx (105 mg, yield 63.6%).

（式中、ｍ、ｎは、上記と同じ意味を表す。） [Comparative Example 1] Synthesis of P3HT _Q

(In the formula, m and n represent the same meaning as described above.)

2-Bromo-3-n-hexyl-5-iodothiophene (1.51 g, 4.05 mmol) dissolved in 35 mL of dry THF in an argon atmosphere was added to a 200 mL eggplant flask equipped with a three-way cock and purged with argon. Added at 0 ° C. Thereto, isopropylmagnesium chloride (2.1 M THF solution, 1.87 mL, 3.93 mmol) was added with a syringe, and the mixture was stirred at 0 ° C. for 2 hours. A solution of Ni (dppp) Cl ₂ (62.7 mg, 0.160 mmol) suspended in dry THF (6 mL) was added to the reaction solution at 0 ° C., and the mixture was stirred at room temperature for 1 hour. Ethinyl magnesium chloride (0.5 M THF solution, 1.4 mL, 0.696 mmol) was added to the reaction solution with a syringe at 0 ° C., and the mixture was stirred at 0 ° C. for 15 minutes, and then the reaction solution was poured into a large amount of cold methanol. . The insoluble material was collected by suction filtration and washed with methanol and hexane to obtain P3HT _Q (441 mg, yield 65.7%).
¹ H NMR (600 MHz, CDCl ₃ ) δ 6.98 (s, 30.8H), 3.53 (s, 1H), 2.80 (t, 62.0H), 1.71 (quint, 63.5H), 1.44-1.30 (m, 191.8H ), 0.91 (t, 94.6H).
GPC (eluent: chloroform, polystyrene standard): RI signal, Mn = 6,700, Mw / Mn = 1.12. UV signal, Mn = 6,730, Mn / Mw = 1.12.
As a result of MALDI-TOFF analysis, the presence of both-end ethynyl compounds was confirmed, and the content ratio was confirmed to be 17.6% from the results of ¹ H-NMR analysis.

Claims (11)

Following formula (1)

(In the formula, X ¹ and X ² each independently represent a halogen atom, and R ¹ and R ² each independently represent a monovalent organic group or a hydrogen atom that does not change before and after the polymerization reaction. ¹ and R ² are not simultaneously hydrogen atoms.)
A 2,5-dihalothiophene compound represented by the following formula (2)

(Wherein R ³ represents an alkyl group having 1 to 5 carbon atoms, and X ³ represents a chlorine atom, a bromine atom or an iodine atom), followed by reaction of the polymerization catalyst. After polymerization in the presence, the reaction product is quenched with hydrochloric acid and the following formula (3)

(Wherein X ² , R ¹ and R ² represent the same meaning as described above, m represents an integer of 1 or more, and n represents an integer of 2 or more.)
A polymer represented by the following formula (A) is obtained, which is then subjected to a coupling reaction with trialkylsilylacetylene in the presence of a coupling catalyst and then desilylated:

(In the formula, R ¹ , R ² , m and n represent the same meaning as described above.)
The manufacturing method of the one terminal modified polythiophene represented by these. The method for producing one-end-modified polythiophene according to claim 1, wherein X ¹ is an iodine atom, and X ² is a bromine atom.   The method for producing a one-terminal modified polythiophene according to claim 1 or 2, wherein the monovalent organic group that does not change before and after the polymerization reaction is a monovalent hydrocarbon group having 1 to 20 carbon atoms. The method for producing a one-terminal modified polythiophene according to claim 1 or 2, wherein either ^one of R ¹ and R ² is a linear alkyl group having 1 to 10 carbon atoms, and the other is a hydrogen atom. Said R < ³ > is an isopropyl group, The manufacturing method of the one-end modified polythiophene of any one of Claims 1-4.   The method for producing a single-end modified polythiophene according to any one of claims 1 to 5, wherein the trialkylsilylacetylene is trimethylsilylacetylene.   The said polymerization catalyst is a nickel catalyst, The manufacturing method of the one-end modified polythiophene of any one of Claims 1-6. The single-end modified polythiophene represented by the formula (A) obtained by the production method according to any one of claims 1 to 7 is represented by the following formula (4):

(In the formula, R ⁴ represents an alkyl group having 1 to 10 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, and p represents an integer of 2 or more.)
It is made to react with the poly 2-oxazoline which has the terminal azide group represented by following formula (B)

(Wherein R ¹ , R ² , R ⁴ , n, m and p have the same meaning as described above.)
The manufacturing method of the block copolymer represented by these. Block copolymer represented by the formula (B) generated by the reaction of the one-end modified polythiophene represented by the formula (A) and the poly 2-oxazoline having a terminal azide group represented by the formula (4) A first step of filtering the reaction solution containing the union through a column filled with neutral aluminum oxide;
A second step of filtering the precipitate formed by adding diethyl ether to the methanol solution after dissolving the residue obtained by distilling off the solvent from the filtrate obtained in the first step in methanol; ,
The third step of dissolving the filtrate obtained in the second step in tetrahydrofuran and adding hexane to the solution to precipitate the block copolymer represented by the formula (B). The manufacturing method of the block copolymer of description. One terminal modified polythiophene represented by the following formula (A).

(In the formula, R ¹ and R ² each independently represent a monovalent organic group or a hydrogen atom that does not change before and after the polymerization reaction, but R ¹ and R ² do not simultaneously become a hydrogen atom. Represents an integer of 1 or more, and n represents an integer of 2 or more.) A block copolymer represented by the following formula (B).

(In the formula, R ¹ and R ² each independently represents a monovalent organic group or a hydrogen atom that does not change before and after the polymerization reaction, but R ¹ and R ² do not simultaneously become a hydrogen atom, ⁴ represents an alkyl group having 1 to 10 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, m represents an integer of 1 or more, n represents an integer of 2 or more, and p represents an integer of 2 or more. Represents.)