Phosphine-palladium complex, polymerization catalyst, and method for producing aromatic polymer

Abstract

The purpose of the present invention is to provide a novel phosphine-palladium complex useful as a polymerization catalyst that functions effectively in catalyst-transfer condensation polymerization, and a polymerization catalyst and a method for producing an aromatic polymer using the same.　The present invention is a phosphine-palladium complex represented by general formula (1). (In the formula, R1 represents a C1-4 alkyl group or a C1-4 alkoxy group, and t represents an integer of 0-4. Ar represents a monovalent group containing an aromatic ring. X represents a halogeno group or a sulfonate group represented by the general formula:-SO3Z, and Z represents a substituted or unsubstituted hydrocarbon group. A represents a substituted or unsubstituted adamantyl group or an aryl group represented by general formula (2).

Description

Phosphine palladium complex, polymerization catalyst, and method for producing aromatic polymer

[0001] The present invention relates to a phosphine palladium complex, a polymerization catalyst using the same, and a method for producing an aromatic polymer.

[0002] Since π-conjugated polymers can change from semiconductors to metals through p-type or n-type doping, such as oxidation or reduction, active research is being conducted to utilize their electrical and optical properties to apply them to capacitors, photoelectric conversion materials, organic electroluminescent materials, and organic field-effect transistors. Among these, π-conjugated polymers with aromatic rings are considered difficult to control the molecular weight of the resulting polymer and to quantitatively introduce terminal functional groups.

[0003] The present inventors have discovered that the Kumada-Tamao coupling polymerization of Grignard-type monomers using a nickel catalyst proceeds through a polymerization mechanism in which the catalyst migrates to the growing end of the molecule (catalyst transfer chain condensation polymerization), giving rise to polymers with controlled molecular weights and molecular weight distributions. They have reported that π-conjugated polymers such as polythiophenes, polyphenylenes, polyfluorenes, and polypyrroles can be precisely synthesized by this catalyst transfer chain condensation polymerization (see Non-Patent Documents 1 and 2, etc.).

[0004] The present inventors have also reported that catalyst transfer chain condensation polymerization also occurs in polymerization using the Suzuki-Miyaura coupling reaction with a palladium catalyst, and that polyfluorenes, polyphenylenes, polythiophenes, and their block copolymers can be synthesized in a controlled manner (see Patent Document 1, Non-Patent Documents 3 to 5, etc.).

[0005] However, there is a problem in that there are only a few types of palladium catalysts that function effectively in catalyst transfer chain condensation polymerization.

[0006] JP 2009-215538 A

[0007] Macromolecules, 2008, 41, 7271-7273Chem. Rev. , 2009, 109, 5595-5619J. Am. Chem. Soc. , 2007, 129, 7236-7237 Macromolecules, 2010, 43, 7095-7100 Macromolecules, 2018, 51, 364-369

[0008] An object of the present invention is to provide a novel phosphine palladium complex useful as a polymerization catalyst that functions effectively in catalyst transfer chain condensation polymerization, a polymerization catalyst using the same, and a method for producing an aromatic polymer.

[0009] In the course of searching for a palladium catalyst that functions effectively in catalyst transfer chain condensation polymerization, the present inventors discovered that a specific phosphine palladium complex having a novel adamantyl group is a polymerization catalyst that functions effectively in catalyst transfer chain condensation polymerization, and thus completed the present invention.

[0010] A first aspect of the present invention is a phosphine palladium complex represented by the following general formula (1):

[0011] (In the formula, R １ represents an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and t represents an integer of 0 to 4. Ar represents a monovalent group containing an aromatic ring. X represents a halogeno group or a group represented by the general formula: -SO ３ Z represents a sulfonate group, and Z represents a substituted or unsubstituted hydrocarbon group. A represents a substituted or unsubstituted adamantyl group or an aryl group represented by the following general formula (2):

[0012] (In the formula, R ２ ~R ６ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group, or a group represented by the general formula: -N(R ７ ) (R ８ ), and R ７ ~R ８ each independently represents an alkyl group having 1 to 5 carbon atoms.

[0013] The second aspect of the present invention is a polymerization catalyst containing the phosphine palladium complex of the first aspect.

[0014] The third invention provided by the present invention is a method for producing an aromatic polymer, comprising a polycondensation step of polycondensing an aromatic compound represented by the following general formula (3) in the presence of the polymerization catalyst of the second invention:

[0015] (In the formula, Ar １ represents a divalent group containing an aromatic ring. １ represents a halogeno group, a nitro group, or —SO ３ Z １ and Z represents a sulfonate group represented by the formula: １ represents a substituted or unsubstituted hydrocarbon group. １ each independently represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group, and two Q １ may be bonded to each other to form a ring.)

[0016] According to the present invention, it is possible to provide a novel phosphine palladium complex useful as a polymerization catalyst that functions effectively in catalyst transfer chain condensation polymerization, as well as a polymerization catalyst and a method for producing an aromatic polymer using the same.

[0017] 1 is a schematic diagram showing an example of a reaction mechanism for catalyst transfer chain condensation polymerization in the aromatic polymer production method of the present invention, and shows a GPC chart of polyfluorene (14) obtained by the first polymerization reaction in Example 7 and a GPC chart of polyfluorene (14)-polythiophene (13) block copolymer obtained by the second polymerization reaction (two-stage charging method).

[0018] The present invention will be described below based on preferred embodiments. The phosphine palladium complex of the present invention represented by the general formula (1) may be simply referred to as a "phosphine palladium complex."

[0019] Ad in the general formula (1) １ is a substituent R １ represents an adamantyl group which may have t groups. １ represents an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms; and t represents an integer of 0 to 4.

[0020] Examples of the alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, and an n-butyl group.

[0021] Examples of the alkoxy group having 1 to 4 carbon atoms include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, and an n-butoxy group.

[0022] In the general formula (1), t is 0, that is, Ad １ is preferably an unsubstituted adamantyl group.

[0023] Ar in the general formula (1) represents a monovalent group containing an aromatic ring. Examples of the aromatic ring include monocyclic aromatic rings such as a benzene ring, a pyridine ring, a 1,2-diazine ring, a 1,3-diazine ring, a 1,4-diazine ring, a 1,3,5-triazine ring, a furan ring, a pyrrole ring, a thiophene ring, a pyrazole ring, an imidazole ring, an oxazole ring, a thiazole ring, an oxadiazole ring, a thiadiazole ring, and an azadiazole ring; fused polycyclic aromatic rings formed by condensing two or more independently selected from the monocyclic aromatic rings; and the monocyclic aromatic ring and / or the fused polycyclic aromatic ring. Examples of the aromatic ring assembly include an aromatic ring assembly in which two or more rings independently selected from fused polycyclic aromatic rings are linked by a divalent atom or group such as a single bond, a methylene group, an ethylene group, an ethenylene group, an ethynylene group, an oxygen atom, a sulfur atom, an imino group, a carbonyl group, or a sulfonyl group; and a bridged polycyclic aromatic ring having one or more bridges consisting of a divalent group such as a methylene group, an ethylene group, a carbonyl group, or a sulfonyl group, which links two adjacent aromatic rings in the fused polycyclic aromatic ring or the aromatic ring assembly.

[0024] These aromatic rings may be substituted with the above-mentioned alkyl groups having 1 to 4 carbon atoms or alkoxy groups having 1 to 4 carbon atoms.

[0025] In the present invention, Ar in general formula (1) is preferably a substituted or unsubstituted phenyl group, and the substituent in the substituted phenyl group is preferably an alkyl group having 1 to 4 carbon atoms.

[0026] The substituted phenyl group is particularly preferably a group represented by the following general formula (4a) or (4b).

[0027] (In the formula, R １１ represents an alkyl group having 1 to 4 carbon atoms.

[0028] In the general formula (1), X represents a halogeno group or a group represented by the general formula: -SO ３ It represents a sulfonate group represented by Z, where Z represents a substituted or unsubstituted hydrocarbon group.

[0029] Examples of the halogeno group include a chloro group, a bromo group, and an iodo group.

[0030] Examples of the unsubstituted hydrocarbon group include alkyl groups having 1 to 50 carbon atoms, such as methyl, ethyl, isopropyl, butyl, and isobutyl; cyclic saturated hydrocarbon groups having 3 to 50 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl; alkenyl groups having 2 to 50 carbon atoms, such as ethenyl and propenyl; aryl groups having 6 to 50 carbon atoms, such as phenyl and 1-naphthyl; and aralkyl groups having 7 to 50 carbon atoms, such as benzyl, 2-phenylethyl, 1-phenylpropyl, 2-phenylpropyl, 3-phenylpropyl, 1-phenylbutyl, 2-phenylbutyl, 3-phenylbutyl, and 4-phenylbutyl. Of these, hydrocarbon groups having 1 to 8 carbon atoms are preferred.

[0031] In addition, examples of the substituent in the substituted hydrocarbon group include the above-mentioned alkyl groups having 1 to 4 carbon atoms and halogeno groups.

[0032] In the present invention, X in the general formula (1) is preferably a halogeno group, and particularly preferably a bromo group.

[0033] A in the general formula (1) represents a substituted or unsubstituted adamantyl group or an aryl group represented by the general formula (2).

[0034] Examples of the substituent in the substituted adamantyl group include the above-mentioned alkyl groups having 1 to 4 carbon atoms and alkoxy groups having 1 to 4 carbon atoms.

[0035] R in the general formula (2) ２ ~R ６ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group, or a group represented by the general formula: -N(R ７ ) (R ８ ), and R ７ ~R ８ each independently represents an alkyl group having 1 to 5 carbon atoms.

[0036] R ２ ~R ６ and R ７ ~R ８ Examples of the alkyl group having 1 to 5 carbon atoms represented by the formula (I) include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and an n-pentyl group.

[0037] R ２ ~R ６ Examples of the alkoxy group having 1 to 5 carbon atoms represented by the formula (I) include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, and an n-pentyloxy group.

[0038] In the present invention, when A in general formula (1) is an aryl group represented by general formula (2), it is particularly preferable that A be an aryl group represented by the following general formula (2a) or (2b), from the viewpoint of increasing solubility and catalytic activity.

[0039] (R in the formula ７ and R ８ is the same as in general formula (2), and R ９ represents an alkyl group having 1 to 5 carbon atoms.

[0040] R ９ Examples of the alkyl group having 1 to 5 carbon atoms represented by the formula (I) include the same groups as those mentioned above.

[0041] The method for producing the phosphine palladium complex of the present invention includes the steps of: 1) reacting a compound represented by the general formula: P(Ad １ ) ２ A (Ad in the formula １and A are defined as in general formula (1).) with an aromatic compound defined as general formula: Ar-X (where Ar and X are defined as in general formula (1)) (see J. Am. Chem. Soc., 126, 1184 (2004)). However, since it tends to be industrially difficult to isolate the resulting phosphine palladium complex, it is preferred to produce the phosphine palladium complex from (1,5-cyclooctadiene)bis(trimethylsilylpalladium(II) (5), a phosphine derivative (6), and an aryl halide compound (7) according to the following reaction scheme (1) (see, for example, Organic Letters 2017, 19, 2853-2856).

[0042] (Ad in the formula １ , A, Ar and X are defined as in general formula (1).

[0043] When the phosphine palladium complex of the present invention is produced by the above method 1), the phosphine palladium complex of the present invention is produced by the method of the general formula: P(Ad １ ) ２ A (Ad in the formula １ and A are defined as in general formula (1).) is reacted with an aromatic compound represented by the general formula: Ar-X (wherein Ar and X are defined as above), and then, without isolating the phosphine palladium complex of the present invention contained in the reaction solution, a reagent necessary for the polycondensation reaction can be added to the reaction solution to carry out polycondensation.

[0044] The phosphine derivative (6) can be easily produced by a known method (see, for example, European Journal of Organic Chemistry, 2020, 1122-1128 and WO2017 / 075581 pamphlet).

[0045] The phosphine palladium complex of the present invention is suitable for polymerization using a transition metal complex as a catalyst, such as coupling polymerization, chain condensation polymerization, and catalyst transfer chain condensation polymerization.

[0046] The method for producing an aromatic polymer of the present invention involves carrying out a Suzuki-Miyaura coupling reaction using the phosphine palladium complex of the present invention as a polymerization catalyst in catalyst transfer chain condensation polymerization. The aromatic compound used as a monomer in the production method of the present invention is not particularly limited as long as it is a boron compound used in a conventional Suzuki-Miyaura coupling reaction, but is preferably an aromatic compound represented by the following general formula (3). That is, the method for producing an aromatic polymer of the present invention comprises a polycondensation step of polycondensing an aromatic compound represented by the following general formula (3) in the presence of a polymerization catalyst containing the phosphine palladium complex of the present invention.

[0047] (In the formula, Ar １ represents a divalent group containing an aromatic ring. １ represents a halogeno group, a nitro group, or —SO ３ Z １ and Z represents a sulfonate group represented by the formula: １ represents a substituted or unsubstituted hydrocarbon group. １ each independently represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group, and two Q １ may be bonded to each other to form a ring.)

[0048] Ar in the general formula (3) １represents a divalent group containing an aromatic ring. Examples of the aromatic ring include monocyclic aromatic rings such as a benzene ring, a pyridine ring, a 1,2-diazine ring, a 1,3-diazine ring, a 1,4-diazine ring, a 1,3,5-triazine ring, a furan ring, a pyrrole ring, a thiophene ring, a pyrazole ring, an imidazole ring, an oxazole ring, a thiazole ring, an oxadiazole ring, a thiadiazole ring, and an azadiazole ring; fused polycyclic aromatic rings formed by condensing two or more independently selected from the monocyclic aromatic rings; and monocyclic aromatic rings and / or fused polycyclic aromatic rings. Examples of the aromatic ring assembly include an aromatic ring assembly in which two or more rings independently selected from fused polycyclic aromatic rings are linked by a divalent atom or group such as a single bond, a methylene group, an ethylene group, an ethenylene group, an ethynylene group, an oxygen atom, a sulfur atom, an imino group, a carbonyl group, or a sulfonyl group; and a bridged polycyclic aromatic ring having one or more bridges consisting of a divalent group such as a methylene group, an ethylene group, a carbonyl group, or a sulfonyl group, which links two adjacent aromatic rings in the fused polycyclic aromatic ring or the aromatic ring assembly.

[0049] In the aromatic ring, a hydrogen atom bonded to a carbon atom may be substituted with a substituent. Examples of the substituent include a halogeno group, a cyano group, and a hydrocarbon group. When the aromatic ring contains a nitrogen atom, a hydrogen atom bonded to the nitrogen atom may be substituted with a hydrocarbon group. When there are two or more substituents on the carbon atom and / or two or more substituents on the nitrogen atom, two or more substituents selected from these may be bonded to form a ring.

[0050] Examples of the hydrocarbon group for the substituent include alkyl groups having 1 to 50 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, pentyl, hexyl, nonyl, dodecyl, pentadecyl, octadecyl, and docosyl groups; saturated cyclic hydrocarbon groups having 3 to 50 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclononyl, cyclododecyl, norbornyl, and adamantyl groups; alkenyl groups having 2 to 50 carbon atoms, such as ethenyl, propenyl, 3-butenyl, 2-butenyl, 2-pentenyl, 2-hexenyl, 2-nonenyl, and 2-dodecenyl groups; phenyl, 1-naphthyl, and 2-naphthyl groups. aryl groups having 6 or more carbon atoms such as a 2-methylphenyl group, a 3-methylphenyl group, a 4-methylphenyl group, a 4-ethylphenyl group, a 4-propylphenyl group, a 4-isopropylphenyl group, a 4-butylphenyl group, a 4-t-butylphenyl group, a 4-hexylphenyl group, a 4-cyclohexylphenyl group, a 4-adamantylphenyl group, and a 4-phenylphenyl group; and aralkyl groups having 7 to 50 carbon atoms such as a phenylmethyl group, a 1-phenyleneethyl group, a 2-phenylethyl group, a 1-phenyl-1-propyl group, a 1-phenyl-2-propyl group, a 2-phenyl-2-propyl group, a 3-phenyl-1-propyl group, a 4-phenyl-1-butyl group, a 5-phenyl-1-pentyl group, and a 6-phenyl-1-hexyl group.

[0051] The hydrocarbon group of the substituent may have a heteroatom such as O, N, or S, and may also have a group such as a carbonyl group, an oxycarbonyl group, an aminocarbonyl group, a sulfonyl group, an amino group, a mercapto group, a hydroxy group, a carboxyl group, a nitro group, a halogeno group, or a cyano group.

[0052] X in general formula (3) １ represents a halogeno group, a nitro group, or —SO ３ Z １ and Z represents a sulfonate group represented by the formula: １ represents a substituted or unsubstituted hydrocarbon group.

[0053] Examples of the halogeno group include a chloro group, a bromo group, and an iodo group.

[0054] Examples of the unsubstituted hydrocarbon group include alkyl groups having 1 to 50 carbon atoms, such as methyl, ethyl, isopropyl, butyl, and isobutyl; cyclic saturated hydrocarbon groups having 3 to 50 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl; alkenyl groups having 2 to 50 carbon atoms, such as ethenyl and propenyl; aryl groups having 6 to 50 carbon atoms, such as phenyl and 1-naphthyl; and aralkyl groups having 7 to 50 carbon atoms, such as benzyl, 2-phenylethyl, 1-phenylpropyl, 2-phenylpropyl, 3-phenylpropyl, 1-phenylbutyl, 2-phenylbutyl, 3-phenylbutyl, and 4-phenylbutyl. Of these, hydrocarbon groups having 1 to 8 carbon atoms are preferred.

[0055] Furthermore, examples of the substituent in the substituted hydrocarbon group include the above-mentioned alkyl groups having 1 to 4 carbon atoms and halogeno groups.

[0056] In the present invention, X in the general formula (3) １ is preferably a chloro group, a bromo group or a trifluoromethylsulfo group.

[0057] Q in general formula (3) １ each independently represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group, and two Q １ may be bonded to each other to form a ring.

[0058] Q １Examples of the hydrocarbon group represented by the formula (I) include alkyl groups having 1 to 50 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, pentyl, hexyl, nonyl, dodecyl, pentadecyl, octadecyl, and docosyl groups; cyclic saturated hydrocarbon groups having 3 to 50 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclononyl, cyclododecyl, norbornyl, and adamantyl groups; alkenyl groups having 2 to 50 carbon atoms, such as ethenyl, propenyl, 3-butenyl, 2-butenyl, 2-pentenyl, 2-hexenyl, 2-nonenyl, and 2-dodecenyl groups; phenyl, 1-naphthyl, 2-naphthyl groups, Examples of suitable aryl groups include aryl groups having 6 to 50 carbon atoms, such as a 2-methylphenyl group, a 3-methylphenyl group, a 4-methylphenyl group, a 4-ethylphenyl group, a 4-propylphenyl group, a 4-isopropylphenyl group, a 4-butylphenyl group, a 4-t-butylphenyl group, a 4-hexylphenyl group, a 4-cyclohexylphenyl group, a 4-adamantylphenyl group, and a 4-phenylphenyl group; and aralkyl groups having 7 to 50 carbon atoms, such as a phenylmethyl group, a 1-phenyleneethyl group, a 2-phenylethyl group, a 1-phenyl-1-propyl group, a 1-phenyl-2-propyl group, a 2-phenyl-2-propyl group, a 3-phenyl-1-propyl group, a 4-phenyl-1-butyl group, a 5-phenyl-1-pentyl group, and a 6-phenyl-1-hexyl group.

[0059] The substituent of the hydrocarbon group may be the above-mentioned alkyl group having 1 to 4 carbon atoms, halogeno group, or the like.

[0060] In the present invention, Q in general formula (3) １ is preferably an alkyl group, more preferably a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a pentyl group, a hexyl group or a nonyl group, and particularly preferably a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group or a hexyl group. １When the groups bond together to form a ring, the divalent hydrocarbon groups are preferably 1,2-ethylene, 1,1,2,2-tetramethyl-1,2-ethylene, 1,3-propylene, 2,2-dimethyl-1,3-propylene, 1,2-phenylene, and the like.

[0061] Examples of the aromatic compound represented by general formula (3) include the boron-containing compounds described in paragraphs

[0058] to

[0059] of JP-A-2009-19186 and the boron-containing compounds described in paragraph

[0028] of JP-A-2009-215538.

[0062] The polycondensation step in the method for producing an aromatic polymer of the present invention is preferably carried out in a solvent in the presence of the polymerization catalyst of the present invention and a base, using one or a combination of two or more aromatic compounds represented by general formula (3).

[0063] In the method for producing an aromatic polymer of the present invention, the phosphine palladium complex of the present invention is used as a polymerization catalyst.

[0064] The amount of the polymerization catalyst added is preferably 0.0001 to 10 mol %, more preferably 0.001 to 5 mol %, and particularly preferably 0.01 to 5 mol %, based on the aromatic compound represented by formula (3).

[0065] Examples of the base used in the method for producing an aromatic polymer of the present invention include inorganic salts such as alkali metal carbonates, phosphates, and acetates; and organic salts such as alkali metal hydroxides, cesium carbonate, cesium fluoride, triethylamine, pyridine, morpholine, quinoline, piperidine, DBU, anilines, and tetra-n-butylammonium acetate.

[0066] The amount of the base added is preferably 0.01 to 1000 times by mole, more preferably 0.1 to 100 times by mole, and particularly preferably 1 to 50 times by mole, relative to the amount of the aromatic compound represented by formula (3).

[0067] In the polycondensation step, in order to carry out the polycondensation reaction more efficiently, a phase transfer catalyst and / or a surfactant may be added as necessary.

[0068] As the phase transfer catalyst, known catalysts such as phosphonium salts, ammonium salts, crown ethers, porphyrins, azacrowns and thiocrowns can be used.

[0069] Examples of the phosphonium salt include phosphonium salts such as tributylmethylphosphonium bromide, tetrabutylphosphonium bromide, trioctylmethylphosphonium bromide, trioctylethylphosphonium bromide, tributyldodecylphosphonium bromide, tributylhexadecylphosphonium bromide, trioctylethylphosphonium bromide, tributylmethylphosphonium chloride, tetrabutylphosphonium chloride, trioctylmethylphosphonium chloride, trioctylethylphosphonium chloride, tributyldodecylphosphonium chloride, tributylhexadecylphosphonium chloride, and trioctylethylphosphonium chloride.

[0070] Examples of the ammonium salt include ammonium salts such as tributylmethylammonium bromide, tetrabutylammonium bromide, trioctylmethylammonium bromide, trioctylethylammonium bromide, tributyldodecylammonium bromide, tributylhexadecylammonium bromide, trioctylethylammonium bromide, tributylmethylammonium chloride, tetrabutylammonium chloride, trioctylmethylammonium chloride, trioctylethylammonium chloride, tributyldodecylammonium chloride, tributylhexadecylammonium chloride, and trioctylethylammonium chloride.

[0071] The amount of the phase transfer catalyst added is preferably 0.01 to 1000 times by mole, more preferably 0.1 to 100 times by mole, and particularly preferably 1 to 50 times by mole, relative to the amount of the aromatic compound represented by formula (3).

[0072] Examples of surfactants include anionic surfactants, cationic surfactants, amphoteric surfactants, and nonionic surfactants.

[0073] Examples of anionic surfactants include alkali metal salts of alkylbenzenesulfonic acid, fatty acids, and monoalkylphosphates. Examples of cationic surfactants include tetraalkylammonium salts and alkylpyridinium salts. Examples of amphoteric surfactants include long-chain alkylamino acids. Examples of nonionic surfactants include polyethylene glycol and polyvinyl alcohol.

[0074] The amount of the surfactant added is preferably 0.01 to 1000 times by mole, more preferably 0.1 to 100 times by mole, and particularly preferably 1 to 50 times by mole, relative to the amount of the aromatic compound represented by formula (3).

[0075] The solvent used in the polycondensation step is preferably selected appropriately depending on the aromatic polymer to be produced. Typical examples include aromatic hydrocarbons such as benzene, toluene, and xylene; linear or cyclic aliphatic hydrocarbons such as heptane and cyclohexane; halogenated hydrocarbons such as chlorobenzene, dichlorobenzene, and dichloromethane; nitriles such as acetonitrile and benzonitrile; alcohols such as methanol, ethanol, n-propyl alcohol, and isopropyl alcohol; 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. Among these, aromatic hydrocarbons, halogenated hydrocarbons, nitriles, ethers, and nitro compounds are preferred. Furthermore, in the production method of the present invention, water such as distilled water may be used in addition to the solvent.

[0076] The reaction temperature in the polycondensation step is preferably from -100 to 200°C, more preferably from -50 to 150°C, and particularly preferably from -20 to 100°C.

[0077] The reaction time in the polycondensation step is preferably 0.1 minute to 1000 hours, more preferably 1 minute to 500 hours, and particularly preferably 10 minutes to 200 hours.

[0078] The polycondensation reaction can be terminated by adding a polymerization terminator to the reaction system when the desired polymer is produced. As the polymerization terminator, for example, a commonly used protic compound such as methanol, acetic acid, or a methanol solution of hydrochloric acid can be used.

[0079] After the polycondensation reaction is completed, the reaction solvent is removed by a conventional method, and if necessary, purification such as reprecipitation is carried out to obtain the desired aromatic polymer.

[0080] According to the method for producing an aromatic polymer of the present invention, catalyst transfer chain condensation polymerization proceeds by carrying out a Suzuki-Miyaura coupling reaction using the polymerization catalyst of the present invention (see FIG. 1 ). Therefore, living-like polymerization becomes possible despite the fact that it is coupling polymerization, and an aromatic polymer having a high molecular weight and a narrower molecular weight distribution can be produced.

[0081] The present invention will be described below with reference to examples, but the present invention is not limited to these examples. The number average molecular weight (Mn) and weight average molecular weight (Mw) in the examples were evaluated by gel permeation chromatography (Tosoh HLC-8320 GPC apparatus, eluent: chloroform, column: two connected TSK-gel columns (Multipore HZ-M), polystyrene equivalent). Furthermore, PDI indicates the ratio (Mw / Mn) of weight average molecular weight (Mw) to number average molecular weight (Mn).

[0082] Example 1 Synthesis of Compound 4

[0083]

[0084] Under argon, 213 mg (0.489 mmol) of tri(1-adamantyl)phosphine (2) and 150 mL of deoxygenated pentane were placed in a 200 mL pear-shaped flask and stirred at room temperature for 5 minutes. Next, 0.13 mL (0.735 mmol) of 2-bromotoluene (3) and 191 mg (0.492 mmol) of (1,5-cyclooctadiene)bis(trimethylsilylpalladium(II)) (1) were added, and the mixture was stirred at room temperature for 16 hours. The supernatant was decanted and filtered, and 15 mL of deoxygenated pentane was added and the supernatant was decanted and filtered, a process repeated 15 times. Finally, the supernatant was removed with a syringe and dried, yielding 337 mg (0.472 mmol) of compound 4 as a pale yellow solid. Yield: 96.5% １ H-NMR (C ６ D ６ ): δ 7.53 (d, J = 5.5 Hz, 1H), 6.84 (m, 2H), 6.77 (d, J = 6.9Hz, 1H), 3.27 (s, 3H), 2.29 (m, 18H), 1.74 (s, 10H), 1.50 (m, 18H) ３１ P-NMR (C ６ D ６ ): δ 47.6 IR (KBr) 2904, 2847, 1560, 1455, 1343, 1297, 1259, 1183, 1102, 1018, 971, 741, 420 cm －１

[0085] Example 2 Synthesis of Compound 6

[0086]

[0087] Under argon, 184 mg (0.436 mmol) of compound 5 and 177 mg (0.455 mmol) of (1,5-cyclooctadiene)bis(trimethylsilylpalladium(II)(1) were placed in a 30 mL pear-shaped flask and dissolved in 6.0 mL of THF. 2.0 mL of a 0.50 mol / L THF solution of 4-tert-butylbromobenzene was added thereto. After stirring at room temperature for 16 hours, the THF was distilled off under reduced pressure, and 20 mL of deoxygenated hexane was added and stirred. The mixture was allowed to stand, and the supernatant was removed with a syringe. 20 mL of deoxygenated hexane was again added, and the mixture was stirred, and the mixture was allowed to stand, and the supernatant was removed. This process was repeated eight times, and the mixture was dried under reduced pressure to obtain 107 mg (0.144 mmol) of compound 6 as a pale yellow solid. Yield: 33.0% １ H-NMR (CDCl ３ ): δ 7.67 (m, 2H), 7.33 (m, 2H), 6.66 (m, 2H), 6.12 (d, J = 8.0Hz, 2H), 3.02 (s, 6H) 2.45-1.61 (m, 39H) ３１ P-NMR (C ６ D ６ ): δ 42.1 IR (KBr) 2902, 2847, 1598, 1509, 1447, 1362, 1302, 1201, 1096, 809, 517, 456, 420 cm －１

[0088] Example 3 Synthesis of Compound 8

[0089]

[0090] Under argon, 124 mg (0.283 mmol) of compound 7 and 110 mg (0.283 mmol) of (1,5-cyclooctadiene)bis(trimethylsilylpalladium(II)(1) were placed in a 20 mL pear-shaped flask, and 3.0 mL of a 0.20 mol / L THF solution of 2-bromotoluene was added thereto. After stirring at room temperature for 1 hour, 4.0 mL of deoxygenated hexane was added, and the mixture was stirred at room temperature for 24 hours. The precipitate was filtered and dried to obtain 179 mg (0.251 mmol) of compound 8 as a pale yellow solid. Yield: 88.7% １ H-NMR (C ６ D ６):δ 7.95-7.80 (m, 2H), 6.88-6.81 (m, 4H), 6.79-6.73 (m, 2H), 4.12 (sept, J = 6.0Hz, 1H), 3.25 (s, 3H), 2.40-1.58 (m, 30H), 1.05 (d, J = 6.0Hz, 6H) ３１ P-NMR (C ６ D ６ ): δ 58.7 IR (KBr) 2905, 2847, 1592, 1498, 1454, 1282, 1247, 1185, 1105, 737, 499, 423 cm －１

[0091] (Example 4) <Mobility Measurement> To confirm whether a part of the catalyst (the Pd-L site in Figure 1) effectively moves on the pi surface of the polymer and whether reductive elimination-oxidative addition proceeds quantitatively within the same polymer, evaluation was performed according to Macromolecules, 2018, 51, 364-369.

[0092]

[0093] (Test method) 1,4-dibromo-2,5-bis(hexyloxy)benzene (9) 105 mg (0.241 mmol), phenylboronic acid pinacol ester (10) 22.4 mg (0.110 mmol), 18-crown-6-ether 349 mg, 2M K ３ P.O. ４ To 0.23 mL (0.460 mmol) of the solution and 2.5 mL of dry THF, 0.00770 mmol of a polymerization catalyst (compound 4, 6, or 8) was added, and the mixture was stirred at room temperature for 24 hours. 6 M hydrochloric acid was added to terminate the reaction, followed by extraction with methylene chloride, and the organic layer was dried over anhydrous magnesium sulfate. After filtration, the solvent was distilled off under reduced pressure, and naphthalene was added to the resulting compound. １ The ratio of compound 11 to compound 12 was calculated using H-NMR. The results are shown in Table 1. Note that a higher production ratio of compound 11 indicates a higher mobility of Pd-L.

[0094]

[0095] Table 1 shows that the production of compound 12 was not observed in the test, but only compound 11 was observed. This suggests that the phosphine palladium complex obtained in this example is a polymerization catalyst suitable for catalyst transfer chain condensation polymerization reactions in which Pd-L effectively migrates to the growing terminal to cause polymerization to proceed, i.e.

[0096] Example 5 Polymerization of Thiophene Monomer (13)

[0097]

[0098] Under an argon atmosphere, 43.95 mg (0.105 mmol) of thiophene monomer (13), 71.2 mg (0.468 mmol) of cesium fluoride, 215 mg (0.814 mmol) of 18-crown-6-ether, 7.0 mL of deoxygenated THF, and 0.45 mL of deoxygenated distilled water were added to a 30 mL round-bottom flask and stirred for 10 minutes to prepare a monomer solution. Also, under an argon atmosphere, 7.21 mg (0.0101 mmol, 10 mol%) of polymerization catalyst (4) and 1.0 mL of deoxygenated THF were added to a separate pear-shaped flask and stirred for 10 minutes to prepare a catalyst solution. The catalyst solution was added to the monomer solution using a cannula and stirred at room temperature for 5 hours. The reaction was then quenched by adding 5 M hydrochloric acid. The mixture was extracted with 50 mL of chloroform, and the solvent was concentrated under reduced pressure to obtain a black crude product. Yield: 87% Mn(PDI): 3200 (1.15).

[0099] Example 6 Polymerization of Fluorene Monomer (14)

[0100]

[0101] Under an argon atmosphere, 43.95 mg (0.105 mmol) of fluorene monomer (14), 71.2 mg (0.468 mmol) of cesium fluoride, 215 mg (0.814 mmol) of 18-crown-6-ether, 7.0 mL of deoxygenated THF, and 0.45 mL of deoxygenated distilled water were added to a 30 mL round-bottom flask and stirred for 10 minutes to prepare a monomer solution. Under an argon atmosphere, 7.21 mg (0.0101 mmol, 10 mol%) of polymerization catalyst (4) and 1.0 mL of deoxygenated THF were added to a separate pear-shaped flask and stirred for 10 minutes to prepare a catalyst solution. The catalyst solution was added to the monomer solution using a cannula and stirred at room temperature for 5 hours. The reaction was then quenched by adding 5 M hydrochloric acid. The mixture was extracted with 50 mL of chloroform, and the solvent was concentrated under reduced pressure to obtain a black crude product. Yield: 98%. Mn (PDI): 7800 (1.24).

[0102] (Example 7) <Block copolymerization>

[0103]

[0104] Copolymerization was carried out using a two-stage monomer charging method. Under an argon atmosphere, 14.55 mg (0.0244 mmol) of fluorene monomer (14), 54.3 mg (0.357 mmol) of cesium fluoride, 82.3 mg (0.312 mmol) of 18-crown-6-ether, 1.8 mL of deoxygenated THF, and 0.11 mL of deoxygenated distilled water were added to a 30 mL round-bottom flask and stirred for 10 minutes to prepare a monomer solution. Under an argon atmosphere, 2.21 mg (0.00310 mmol, 10%) of polymerization catalyst (4) and 1.0 mL of deoxygenated THF were added to a separate pear-shaped flask and stirred for 10 minutes to prepare a catalyst solution. The catalyst solution was added to the monomer solution using a cannula and stirred at room temperature for 5 hours (first polymerization reaction). Subsequently, a monomer solution prepared by dissolving 9.01 mg (0.0214 mmol) of thiophene monomer (13) in 1.0 mL of deoxygenated THF was added to the reaction solution, and the mixture was further stirred at room temperature for 24 hours (second polymerization reaction). 5 M hydrochloric acid was added to the reaction solution, followed by extraction with 50 mL of chloroform. The solvent was concentrated under reduced pressure to obtain a black crude product. Yield: 82% Mn (PDI): 7700 (1.22).

[0105] The dotted line in the GPC chart shown in Figure 2 is the elution curve of polyfluorene (14) obtained by the first polymerization reaction, and the solid line is the elution curve of the polymer obtained by the second polymerization reaction. By adding thiophene monomer (13) to a polymerization system containing polyfluorene (14) obtained by the first polymerization reaction, the elution curve shifts to the higher molecular weight side. This indicates that the polymer obtained by the second polymerization reaction is a polyfluorene (14)-polythiophene (13) block copolymer. Therefore, it is clear that the polymerization catalyst of the present invention functions effectively in catalyst transfer chain condensation polymerization.

Claims

1. A phosphine palladium complex represented by the following general formula (1): (In the formula, R １ represents an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and t represents an integer of 0 to 4. Ar represents a monovalent group containing an aromatic ring. X represents a halogeno group or a group represented by the general formula: -SO ３ A represents a sulfonate group represented by Z, where Z represents a substituted or unsubstituted hydrocarbon group. A represents a substituted or unsubstituted adamantyl group, or an aryl group represented by the following general formula (2): (In the formula, R ２ ~R ６ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group, or a group represented by the general formula: -N(R ７ ) (R ８ ), and R ７ ~R ８ each independently represents an alkyl group having 1 to 5 carbon atoms.

2. The phosphine palladium complex according to claim 1, wherein the aryl group represented by the general formula (2) is an aryl group represented by the following general formula (2a): (R in the formula ７ and R ８ is the same as general formula (2).

3. The phosphine palladium complex according to claim 1, wherein the aryl group represented by the general formula (2) is an aryl group represented by the following general formula (2b): (In the formula, R ９ represents an alkyl group having 1 to 5 carbon atoms.

4. The phosphine palladium complex according to claim 1, wherein Ar in general formula (1) is a substituted or unsubstituted phenyl group, and the substituent in the substituted phenyl group is an alkyl group having 1 to 4 carbon atoms.

5. The phosphine palladium complex according to claim 1, wherein X in the general formula (1) is a halogeno group.

6. A polymerization catalyst comprising the phosphine palladium complex according to claim 1.

7. The polymerization catalyst according to claim 6, which is used for polycondensation.

8. A method for producing an aromatic polymer, comprising a polycondensation step of polycondensing an aromatic compound represented by the following general formula (3) in the presence of the polymerization catalyst according to claim 6: (In the formula, Ar １ represents a divalent group containing an aromatic ring. １ is a halogeno group, a nitro group, or -SO ３ Z １ Z represents a sulfonate group represented by the formula: １ represents a substituted or unsubstituted hydrocarbon group. １ each independently represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group; １ may be bonded to each other to form a ring.)

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