JP4731942B2 - Polythiophene - Google Patents

Description

The present invention relates to polythiophene.

Polythiophene is widely known to be useful for advanced functional materials such as conductive materials, photoelectric conversion materials, EL materials, nonlinear optical materials, and FET materials, and has functions such as water solubility, metal-capturing ability, and self-doping. A polythiophene having a substituent having a hetero atom has been studied in the hope of imparting (Non-patent Document 1).

Chem. Rev. 92,711 (1992)

A polythiophene having a substituent having a heteroatom, which has such characteristics as being highly self-integrated and capable of forming a precise layer structure, is required.
An object of the present invention is to provide a polythiophene having a substituent having a hetero atom, which has characteristics such as high self-assembly and formation of a precise layer structure.

（式中、Ｒ¹およびＲ²はそれぞれ独立に、ヘテロ原子を含む官能基を少なくとも１つ有する置換基または水素原子であり、Ｒ¹およびＲ²の１つ以上がヘテロ原子を含む官能基を少なくとも１つ有する置換基であるか、または、Ｒ¹およびＲ²が一緒になってヘテロ原子を含む官能基を少なくとも１つ有する環を形成している。）
また、本発明は、 下式（ＩＩ）で表されるチオフェン化合物を有機溶媒中で有機マグネシウム試薬と反応させ、エチレンジホスフィン化合物／ニッケル触媒の共存下で重合させて得られることを特徴とする上記のポリチオフェンを提供するものである。

（式中、Ｒ¹およびＲ²は式（Ｉ）のそれらと同じ定義である。Ｘ¹およびＸ²はそれぞれ独立にハロゲン原子を表す。）
That is, the present invention includes a repeating unit represented by the following formula (I) and has a number average molecular weight of 1,000 or more, Mw / Mn (Mw represents a number average molecular weight, and Mn represents a weight average molecular weight). Is in the range of 1.0 to 1.8.

Wherein R ¹ and R ² are each independently a substituent or a hydrogen atom having at least one functional group containing a hetero atom, and one or more of R ¹ and R ² are functional groups containing a hetero atom. Or at least one substituent, or R ¹ and R ² are combined to form a ring having at least one functional group containing a hetero atom.)
Further, the present invention is obtained by reacting a thiophene compound represented by the following formula (II) with an organomagnesium reagent in an organic solvent and polymerizing in the presence of an ethylenediphosphine compound / nickel catalyst. The polythiophene is provided.

(In the formula, R ¹ and R ² have the same definitions as those in formula (I). X ¹ and X ² each independently represent a halogen atom.)

The polythiophene of the present invention has such characteristics as being highly self-integrated and capable of forming a precise layer structure. The polythiophene of the present invention has high functionality such as water solubility, metal-capturing ability, self-doping, etc. due to the effect of the substituent having a hetero atom, and highly self-integrated due to a narrow molecular weight distribution, and a precise layer structure And is used for advanced functional materials such as conductive materials, photoelectric conversion materials, EL materials, nonlinear optical materials, and FET materials.

  The polythiophene of the present invention is a polythiophene containing a repeating unit represented by the above general formula (I), has a number average molecular weight (Mn) of 1,000 or more, and a molecular weight distribution obtained from the weight average molecular weight (Mw) ( Mw / Mn) is a polythiophene having a ratio of 1.0 to 1.8, and is preferably substantially composed of a repeating unit represented by the general formula (I).

In formula (I), R ¹ and R ² are each independently a substituent having at least one functional group containing a hetero atom or a hydrogen atom, and one or more of R ¹ and R ² are functional groups containing a hetero atom It is a substituent having at least one group, or R ¹ and R ² are combined to form a ring having at least one functional group containing a hetero atom.

Here, as the functional group containing a hetero atom in a substituent having at least one functional group containing a hetero atom, a halogen atom, a hydroxyl group, an ether group, a mercapto group, a thioether group, a primary to tertiary amino group, or 1-3 Examples include a primary phosphino group, a carbonyl group, an ester group, an amide group, a nitrile group, a nitro group, a sulfonic acid group, a phosphoric acid group, and a boric acid group. The functional group is preferably an ether group, a thioether group, a tertiary amino group or a tertiary phosphino group, more preferably an ether group or a tertiary amino group, and even more preferably an ether group. Although the number of the functional group containing the hetero atom in a substituent should just be 1 or more, Preferably it is 1-100, More preferably, it is 1-20, More preferably, it is 1-5.
Other than the functional group containing a hetero atom in the substituents of R ¹ and R ^{2 in} the above general formula, it consists of a carbon atom and a hydrogen atom. Although there is no restriction | limiting in particular in the number of the carbon atoms in this substituent, Preferably it is 1-200, More preferably, it is 1-40, More preferably, it is 1-20. Although there is no restriction | limiting in particular in the number of the hydrogen atoms in this substituent, Preferably it is 3-400, More preferably, it is 3-80, More preferably, it is 3-41.

Specific examples of the substituent having at least one functional group containing a hetero atom of the general formula (I) include methoxy group, dimethylamino group, methyl mercapto group, dimethylphosphino group, ethoxy group, propoxy group, butoxy group, pentoxy group, hexyloxy group, octyloxy group, dodecyloxy group, octadecyloxy group, allyloxy group, a phenoxy group, a methoxymethyl _{group, -O (CH 2 CH 2 O} ) m CH 3 group (where, m is an integer from 1 to 20 _{), - CH 2 O (CH} 2 CH 2 O) n CH 3 group (where, n is an integer of 1 to 20), and the like.

Further, R ¹ and if R ² form at least one having ring functional group containing a hetero atom together, R ¹ and as the group R ² taken together -CH ₂ OCH ₂ - groups, -OCH ₂ CH _{2 O-group, -OCH (CH 3) CH 2} O- groups, such as -OCH ₂ CH ₂ CH ₂ O- group.

As R ¹ and R ² in the general formula (I), preferably an alkoxy group having a carbon number of _{1~20, -O (CH 2 CH 2} O) m CH 3 group (where, m is an integer of from 1 to 10 ), —CH ₂ O (CH ₂ CH ₂ O) _n CH ₃ group (where n is an integer of 1 to 10), hydrogen atom or R ¹ and R ² form a ring as —OCH ₂ CH ₂ O -Group.
More preferably, R ¹ is a hydrogen atom, R ² is an alkoxy group having 1 to 20 carbon atoms, —O (CH ₂ CH ₂ O) _m CH ₃ group (where m is an integer of 1 to 10), —CH ₂ O (CH ₂ CH ₂ O) _n CH ₃ group (where n is an integer of 1 to 10). More preferably, R ¹ is a hydrogen atom, and R ² is a —CH ₂ O (CH ₂ CH ₂ O) nCH ₃ group (where n is an integer of 1 to 10).

Specific examples of the repeating unit represented by the general formula (I) include 3-methoxy-2,5-thiophenylene, 3-dimethylamino-2,5-thiophenylene, 3-methylmercapto-2, 5-thiophenylene, 3-dimethylphosphino-2,5-thiophenylene, 3-ethoxy-2,5-thiophenylene, 3-propoxy-2,5-thiophenylene, 3-butoxy-2,5-thiophenylene 3-hexyloxy-2,5-thiophenylene, 3-dodecyloxy-2,5-thiophenylene, 3-octadecyloxy-2,5-thiophenylene, 3-allyloxy-2,5-thiophenylene, 3-phenoxy -2,5-thiophenylene, 3-methoxymethyl-2,5-thiophenylene, 3- (2-methoxyethoxy) methyl-2,5-thiophenylene, 3 (2- (2-methoxyethoxy) ethoxymethyl) -2,5-thiophenylene, 3- (2- (2- (2-methoxyethoxy) ethoxy) ethoxymethyl) -2,5-thiophenylene, 2,3 -Dimethoxy-2,5-thiophenylene, 2,3- (ethylene-1,2-dioxy) -2,5-thiophenylene, 2,3- (propylene-1,2-dioxy) -2,5-thio Examples include phenylene, 2,3- (propylene-1,3-dioxy) -2,5-thiophenylene, and the like.

  The number average molecular weight (Mn) in the polythiophene of the present invention is usually 1,000 or more, preferably 1,000 to 1,000,000, more preferably 2,000 to 500,000, still more preferably. 3,000 to 100,000.

The molecular weight distribution (Mw / Mn) determined from the weight average molecular weight (Mw) in the polythiophene of the present invention is 1.0 to 1.8, preferably 1.0 to 1.6, more preferably 1. It is 0-1.5, More preferably, it is 1.0-1.4.

The polythiophene of the present invention is more preferably obtained by reacting the thiophene compound represented by the general formula (II) with an organic magnesium reagent in an organic solvent and polymerizing it in the presence of an ethylenediphosphine compound / nickel catalyst.

R ¹ and R ² in the general formula (II) have the same definition as R ¹ and R ² in the general formula (I), and specific examples and preferred examples are also the same. In addition, when R ¹ and R ² have a functional group reactive with an organomagnesium reagent such as a hydroxyl group or a carbonyl group, a protective group may be bonded and the protective group may be eliminated (deprotected) after polymerization. . For such protection and deprotection, for example, a method described in “Protective Groups in Organic Synthesis,” John Wiley and Sons, New York (1981) may be used.

X ¹ and X ² in the general formula (II) are each independently a halogen atom. The halogen atom is preferably a chlorine atom, a bromine atom or an iodine atom.

X ¹ and X ² in the general formula (II) are each preferably an iodine atom and a bromine atom, a bromine atom and a chlorine atom, an iodine atom and an iodine atom, a bromine atom and a bromine atom, an iodine atom and a bromine atom, A chlorine atom is more preferable, and an iodine atom and a bromine atom are further preferable.

Examples of the organic solvent used in the present invention include aromatic hydrocarbons such as benzene, toluene and xylene; chain and cyclic aliphatic hydrocarbons such as heptane and cyclohexane; halogenated hydrocarbons such as chlorobenzene, dichlorobenzene and dichloromethane; acetonitrile And nitriles such as benzonitrile; ethers such as dioxane, tetrahydrofuran and ethylene glycol dimethyl ether; amides such as N, N-dimethylformamide and N-methylpyrrolidone; and nitro compounds such as nitromethane and nitrobenzene. As the reaction solvent, aromatic hydrocarbons or ethers are preferable. These organic solvents may be used alone or as a mixture of two or more. The organic solvent used in the reaction with the magnesium reagent and the organic solvent used in the polymerization may be the same or different.

The amount of the organic solvent used is usually 0.01 to 10,000 mL with respect to 1 g of the thiophene compound represented by the general formula (II), preferably 0.1 to 1,000 mL. Yes, more preferably 1 to 100 mL.

The reaction between the thiophene compound represented by the general formula (II) and the organomagnesium reagent in the present invention is a known reaction called Grignard metathesis reaction described in, for example, JP-A No. 2004-115695.

The organomagnesium reagent used in the present invention includes, for example, the formula R′MgX ′ (wherein R ′ is an alkyl group having 1 to 8 carbon atoms, a vinyl group, or a phenyl group, and X ′ is a chlorine atom or a bromine atom. Or an iodine atom). A particularly preferred organomagnesium reagent is isopropylmagnesium chloride.

  The amount of the organomagnesium reagent used is usually 0.5 to 10 mol, preferably 0.9 to 1.1, based on 1 mol of the thiophene compound represented by the general formula (II). Mol, more preferably 0.95 to 1.05 mol.

  The reaction temperature of the thiophene compound of the present invention, the organomagnesium reagent and the reaction temperature is usually −60 ° C. to 160 ° C., preferably −40 ° C. to 120 ° C., more preferably −20 ° C. to 80 ° C. The reaction time is usually 1 minute to 100 hours, preferably 5 minutes to 24 hours, and more preferably 10 minutes to 6 hours.

  The polymerization with a nickel catalyst in the present invention is a known polycondensation reaction described in, for example, JP-A No. 2004-115695.

The nickel catalyst used in the present invention is not limited as long as the effects of the present invention are exhibited, but an ethylenediphosphine compound / nickel catalyst is preferable from the viewpoint of molecular weight distribution.

As ethylenediphosphine compounds, 1,2-bis (dimethylphosphino) ethane, 1,2-bis (diethylphosphino) ethane, 1,2-bis (di-n-propylphosphino) ethane, 1,2-bis (Diisopropylphosphino) ethane, 1,2-bis (di-t-butylphosphino) ethane, 1,2-bis (dicyclohexylphosphino) ethane, 1,2-bis (diphenylphosphino) ethane, 1,2 -Bis (diphenylphosphino) -1-methylethane, 1,2-bis (diphenylphosphino) -1,2-dimethylethane, 1,2-bis (diphenylphosphino) -1,2-cyclohexane. As the nickel catalyst, a complex composed of an ethylenediphosphine compound and nickel (0) or nickel (II) salt is used. Nickel (II) salts include nickel fluoride, nickel chloride, nickel bromide, nickel iodide, nickel nitrate, nickel sulfate, nickel carbonate, nickel phosphate, nickel acetate, nickel methanesulfonate, nickel trifluoromethanesulfonate, Examples thereof include nickel toluene sulfonate. A particularly preferred nickel catalyst is 1,2-bis (diphenylphosphino) ethane.nickel (II) chloride.

  The amount of the nickel catalyst used is usually 0.0001 to 10 mol% with respect to 1 mol of the thiophene compound represented by the general formula (II), preferably 0.001 to 5 mol%. More preferably, it is 0.01-5 mol%.

The temperature of the polymerization reaction of the present invention is usually −60 ° C. to 100 ° C., preferably −50 ° C. to 60 ° C., more preferably −40 ° C. to 40 ° C. The reaction time is usually 10 minutes to 1,000 hours, preferably 30 minutes to 500 hours, more preferably 1 to 200 hours.

  After the completion of the polymerization reaction, it is preferable to wash the polymerization mixture with an aqueous hydrochloric acid solution or water as necessary, and then evaporate the organic solvent or precipitate the polythiophene by adding a poor solvent. As the poor solvent, a solvent that does not dissolve polythiophene may be used, for example, chain and cyclic aliphatic hydrocarbons such as heptane and cyclohexane; alcohols such as methanol, ethanol, n-propyl alcohol, and iso-propyl alcohol; Water is mentioned, and methanol is preferable. The usage-amount of this poor solvent is 1-1000 mL normally with respect to 10 mL of reaction solvents, Preferably it is 5-100 mL.

Hereinafter, the present invention will be described in more detail based on examples, but the scope of the present invention is not limited by these examples.

Example 1
The reaction was carried out under a nitrogen stream using an eggplant flask equipped with a three-way cock. The flask was dried under reduced pressure while heating with a heat gun, purged with argon, and then returned to room temperature. To this was added 0.426 g (1.01 mmol) of 2-bromo-5-iodo-3- [2- (2-methoxyethoxy) ethoxymethyl] thiophene and 0.0400 g (0.312 mmol) of naphthalene as an internal standard substance, and dried again under reduced pressure. And replaced with argon. After adding 5 ml of dry THF and cooling to 0 ° C., 0.50 ml (1.0 mmol, 1.0 eq) of isopropylmagnesium chloride THF solution (2.0 mol / l) was added, and the mixture was stirred at 0 ° C. for 1 hour. After cooling the reaction solution to -20 ° C, 0.0117 g (0.0222 mmol, 2.2 mol% based on monomer) of 1,2-bis (diphenylphosphino) ethane / nickel chloride suspended in 5 ml of dry THF Was added after cooling to −20 ° C. and stirred at −20 ° C. for 118 hours. After completion of the reaction, 5 M HCl was added, followed by extraction with chloroform. The organic layer was washed with water and then dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure, and the residue was washed with hexane to obtain black-red solid poly (3- (2- (2-methoxyethoxy) ethoxy) methyl-2,5-thiophene) ( ¹ H NMR ( 600 MHz, CDCl ₃ ): 7.25 (s, 1 H), 4.66 (s, 2 H), 3.74 (s, 4 H), 3.68 (t, 2 H), 3.56 (t, 2 H), 3.37 (s , 3 H)). Mn of this polymer was 6520, and Mw / Mn was 1.23.

Comparative Example 1
Except that 1,2-bis (diphenylphosphino) ethane / nickel (II) chloride was replaced with 1,3-bis (diphenylphosphino) propane / nickel (II) chloride, poly ( 3- (2- (2-methoxyethoxy) ethoxy) methyl-2,5-thiophene) was obtained. Mn of this polymer was 7310, and Mw / Mn was 1.89.

As described in JP-A No. 2004-115695, 1,3-bis (diphenylphosphino) propane / nickel chloride catalyst is suitable for polymerization of a thiophene derivative having an alkyl group as a substituent, and has a molecular weight distribution. A narrow polymer was obtained. However, in the polymerization of a polythiophene derivative having a substituent having a hetero atom, as shown in Comparative Example 1, the molecular weight distribution of the polymer synthesized with 1,3-bis (diphenylphosphino) propane / nickel chloride catalyst was wide. A polymer having a narrow molecular weight was obtained by using a 1,2-bis (diphenylphosphino) ethane / nickel chloride catalyst as in Example 1.
Thus, in order to produce the polythiophene having a substituent having a heteroatom of the present invention, ethylene is more suitable than the propylene diphosphine compound / nickel catalyst, which is preferably used for producing poly (alkylthiophene) having a narrow molecular weight distribution. A diphosphine compound / nickel catalyst is preferred.

Claims (3)

The repeating unit represented by the following formula (I) is included, the number average molecular weight is 1,000 or more, and Mw / Mn (Mw represents the number average molecular weight and Mn represents the weight average molecular weight) is 1.0 to A polythiophene characterized by being in the range of 1.8.

Wherein R ¹ and R ² are each independently a substituent having 3 to 20 ether groups or a hydrogen atom, and one or more of R ¹ and R ² are substituents having 3 to 20 ether groups. Oh Ru.) R ¹ Is a hydrogen atom and R ² Is -O (CH ₂ CH ₂ O) _m CH _Three Group (where m is an integer of 2 to 10), -CH ₂ O (CH ₂ CH ₂ O) _n CH _Three The polythiophene according to claim 1, which is a group (where n is an integer of 2 to 10). The thiophene compound represented by the following formula (II) is reacted with an organomagnesium reagent in an organic solvent and polymerized in the presence of an ethylenediphosphine compound / nickel catalyst, and then the organic solvent is evaporated or a poor solvent is added. Including a repeating unit represented by the following formula (I), having a number average molecular weight of 1,000 or more, Mw / Mn (Mw represents a number average molecular weight, and Mn is a weight average) A method for producing polythiophene having a molecular weight of 1.0 to 1.8.

Wherein R ¹ and R ² are each independently a substituent having 3 to 20 ether groups or a hydrogen atom, and one or more of R ¹ and R ² are substituents having 3 to 20 ether groups. is there.)

(In the formula, R ¹ and R ² have the same definitions as those in formula (I). X ¹ and X ² each independently represent a halogen atom.)