JPH09324044A - Production of poly-1,4-phenylene ether - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a less discolored poly-1,4-phenylene ether freed from C-C bond structure and reduced in the content of ortho branches by polymerizing a specified starting phenolic material in the presence of an oxidizing agent and a transition metal complex catalyst. SOLUTION: A starting phenolic material represented by formula I (wherein (m) is the average number of repeating units and is in the range: 1<m) is polymerized at a temperature (0-180 deg.C) equal to or higher than the melting point of the starting material in the presence of an oxidizing agent in an amount equal to or larger than the number of equivalents of the starting material used and 0.01-50mol% transition metal complex catalyst represented by formula II [wherein M is a group 4-11 transition metal; R<1> is an organic group having N, P, O or S as the coordinating atom; R<2> is a trifunctional organic group having N, P, O or S as the coordinating atom; Y is a counter anion; and (y) is the number of Ys and depends on the valence of M].

Description

Detailed Description of the Invention

[0001]

The present invention relates to a method for producing poly-1,4-phenylene ether.

[0002]

2. Description of the Related Art Oxidative polymerization using a transition metal complex catalyst of 2,6-dimethylphenol (for example, see JP-B-63-663).
No. 091, JP-A-59-131627, and many others. )
(2,6-dimethylphenylene ether) (hereinafter referred to as PP
Sometimes abbreviated as E. ) Are known to be useful resins. However, PPE has a disadvantage that it is difficult to melt-mold PPE alone because a methyl group substituted by an aromatic ring is susceptible to oxidative deterioration, and is generally positioned as a general-purpose engineering plastic as a polymer alloy with polystyrene. .

On the other hand, poly-1,4-phenylene ether (hereinafter sometimes abbreviated as PAO) is available from Europ. Polym.
J., 4,275 (1968).
° C (glass transition temperature is 83 ° C), which exceeds the melting point of polyphenylene sulfide (285 ° C), which is generally called super engineering plastic, and has the second highest melting point of polyetheretherketone (334 ° C). Its usefulness as a heat-resistant resin is extremely large.

As a method for producing PAO, Europ. Polym.
J., 4,275 (1968) describes the polymerization of sodium salt of p-bromophenol in the presence of a copper catalyst.
There is a problem that the reaction temperature needs to be as high as 200 ° C. and a salt equivalent to the reaction amount is formed. JP-A-59-
Japanese Patent No. 56426 describes a method for producing PAO by electrolytic oxidation polymerization of phenol, but mass production was difficult because the amount of polymer produced per unit time is governed by the surface area of the electrode. In addition, Japanese Patent Publication No.
No. 918 proposes a method of irradiating 4-phenoxyphenol with light of a specific wavelength in the presence of a photosensitizer. However, phenol is by-produced as polymerization proceeds.
In addition, there is a problem in that mass production is difficult due to the method using light irradiation. Further, Japanese Patent Publication No. 44-28917 proposes a method of heating 4-phenoxyphenol to a temperature at which phenol is distilled, but it requires a high temperature and has a problem that phenol is by-produced. Was.

As a method for solving these problems, an oxidative polymerization method using a transition metal complex catalyst is an excellent method because the reaction temperature is relatively low and the by-product to be eliminated is water. As examples of the oxidative polymerization method using a phenolic transition metal complex catalyst, Japanese Patent Publication No. 36-18692, Industrial Chemistry Magazine, Vol. 72, No. 10, 106 (1969), and Japanese Patent Publication No. Sho 4
However, these methods have a problem that an ortho-position branch or a CC bond structure is generated.

Here, the ortho-position branching means that the benzene ring in the phenol polymer has a 1,2,4-trisubstituted benzene structure, which disrupts the originally desired chain of the 1,4-disubstituted benzene structure. Structure. In addition, the CC bond structure indicates that polymerization of phenol does not occur in the reaction between an oxygen atom and a benzene ring but occurs in a reaction between benzene rings, resulting in a biphenyl structure. When the ortho-branching and the CC bond structure increase, the melting point decreases, and eventually PAO becomes an amorphous resin having no melting point, and loses its usefulness as an ultra-high heat-resistant resin due to its high melting point.

In Japanese Patent Publication No. 36-18692 and Industrial Chemistry Magazine, Vol. 72, No. 10, 106 (1969), the reaction of phenol at the ortho position in catalyzed oxidative polymerization of tertiary amine and cuprous salt is described. It has been proposed to use tertiary amines with bulky substituents (such as 2,6-dimethylpyridine etc.) to prevent terrification. However, the polymer obtained by this method also contains a CC bond structure,
Ortho-position branching was not sufficiently suppressed, and it was not what could be called PAO, such as an amorphous resin in which a melting point was not observed.

On the other hand, Tetrahedron, 23, 2253 (1967)
Phenoxyphenol with cuprous salt and N, N, N ',
Although an example is shown in which oxidative polymerization is carried out using an N′-tetraethylethylenediamine catalyst, the polymer obtained by this method also has many ortho-position branches and no melting point was observed.

[0009]

As described above, in the oxidative polymerization method using a transition metal complex catalyst at present, a large number of ortho-position branches and CC bonds are formed, and a useful polymer has not been obtained. Therefore, the current problem is to produce PAO that can exhibit a melting point. That is, an object of the present invention is to show a controlled, melting point of a structure in which a CC bond structure is not generated and the number of ortho-position branches is small.
An object of the present invention is to provide a method for producing poly-1,4-phenylene ether.

[0010]

Under these circumstances, the present inventors have conducted intensive studies to achieve the above object, and as a result, have determined that a specific raw material can be used in the presence of a specific transition metal complex catalyst. The inventors have found an oxidative polymerization method to be used, and have completed the present invention.

That is, the present invention is represented by the following general formula (I).
The following structural formula (II) is used with a transition metal complex catalyst.
Poly-1,4-phenylene polymerizing the raw material to be produced in the presence of an oxidizing agent
Method for producing nylene ether.(In the formula, M represents a transition metal atom of Groups 4 to 11, and R¹Is
Nitrogen atom, phosphorus atom, oxygen atom or sulfur as a coordinating atom
An organic group having atoms, all R¹Are the same but different
It may be. R¹Form a ring in any combination
May be. R ^TwoIs a nitrogen atom as a coordinating atom, phosphorus atom
A trifunctional organic group containing a child, an oxygen atom or a sulfur atom
Yes, all R^TwoMay be the same or different. Y
Is a counter anion, y is the number of Y,
It is determined by the valence of M. )(Where m represents the number average number of units, and 1 <m
You. ) Next, the present invention will be described in detail.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION

(1) Transition Metal Complex Catalyst The transition metal complex catalyst used in the present invention is a transition metal complex represented by the above general formula (I). In the present invention, a ligand is defined as a chemical dictionary (first edition, Tokyo Chemical Dojin, 19
(1989)), a molecule or ion that is bonded to an atom by a coordination bond. The atoms directly involved in the bond are called coordinating atoms. The hexadentate ligand has 6 coordination atoms
Ligands. Due to the specific polydentate ligand of the transition metal complex, an environment around the transition metal atom can be obtained, which is suitable for obtaining a polymer having no C—C bond structure and a small ortho-branched structure.

In the above general formula (I), M is a transition metal atom of Groups 4 to 11 of the periodic table of elements (IUPAC Inorganic Chemistry Nomenclature Revised Edition 1989). Preferred are transition metal atoms of the first transition element series, and more preferred are vanadium, iron, cobalt, nickel, and copper atoms.
Particularly preferred is a copper atom. As the valence of the transition metal, those normally existing in nature can be appropriately selected and used, and for example, in the case of copper, monovalent or divalent can be used.

R ¹ in the above general formula (I) is an organic group having a nitrogen atom, a phosphorus atom, an oxygen atom or a sulfur atom as a coordinating atom, and all R ¹ may be the same or different. Examples of such an organic group include a nitrogen atom, a phosphorus atom,
Examples thereof include substituted hydrocarbon groups substituted with a group containing an oxygen atom or a sulfur atom. For example, amino group-substituted hydrocarbon group, imino group-substituted hydrocarbon group, azo group-substituted hydrocarbon group, phosphino group-substituted hydrocarbon group, hydroxy group-substituted hydrocarbon group, alkoxy group-substituted hydrocarbon group, carbonyl-containing group-substituted hydrocarbon group , Mercapto group substituted hydrocarbon group, thioalkoxy group substituted hydrocarbon group, thiocarbonyl-containing group substituted hydrocarbon group or heterocyclic ring such as pyridyl group, furyl group, piperidyl group, thienyl group, imidazolyl group, oxazolyl group, thiazolyl group A group having a skeleton,
Examples thereof include a hydrocarbon group substituted with a group having a heterocyclic skeleton.

R ² in the above general formula (I) is a trifunctional organic group having a nitrogen atom, a phosphorus atom, an oxygen atom or a sulfur atom as a coordinating atom, and all R ² are the same or different. Good. Examples of the trifunctional organic group include a nitrogen atom, a phosphorus atom, or a trifunctional substituted hydrocarbon group substituted with a group containing a nitrogen atom, a phosphorus atom, an oxygen atom or a sulfur atom. . Examples of such a trifunctional substituted hydrocarbon group include a trifunctional hydrocarbon group substituted with an amino group, a trifunctional hydrocarbon group substituted with an imino group, and a trifunctional hydrocarbon group substituted with an azo group. Hydrocarbon group, trifunctional hydrocarbon group substituted with phosphino group, trifunctional hydrocarbon group substituted with hydroxy group,
Trifunctional hydrocarbon group substituted with an alkoxy group, trifunctional hydrocarbon group substituted with a carbonyl-containing group, trifunctional hydrocarbon group substituted with a mercapto group, substituted with a thioalkoxy group A trifunctional hydrocarbon group, a trifunctional hydrocarbon group substituted with a group containing thiocarbonyl,
Alternatively, a trifunctional group having a heterocyclic skeleton such as a pyridine ring, a furan ring, a thiophene ring, an imidazole ring, an oxazole ring, or a thiazole ring, or a trifunctional hydrocarbon group substituted with a group having a heterocyclic skeleton, etc. Is.

In the above general formula (I), Y is a counter anion, y is the number of Y, and is determined by the valence of M. The counter anion is not particularly limited, but usually a conjugate base of Bronsted acid is used,
Specific examples include fluoride ion, chloride ion, bromide ion, iodide ion, sulfate ion, nitrate ion,
Carbonate, perchlorate, tetrafluoroborate, hexafluorophosphate, methanesulfonate, trifluoromethanesulfonate, toluenesulfonate, acetate, trifluoroacetate, propionate, benzoate , Hydroxide ion, oxide ion, methoxide ion, ethoxide ion and the like.

Specific examples of the ligand constituting the transition metal complex represented by the above general formula (I) are N, N, N ',
N'-ethylenediaminetetraacetic acid, N, N, N ', N'-
1,3-propylenediaminetetraacetic acid, N, N, N ′,
N'-1,2-phenylenediaminetetraacetic acid, N, N,
N ', N'-tetrakis (2-aminoethyl) ethylenediamine, N, N, N', N'-tetrakis (2-hydroxyethyl) ethylenediamine, N, N, N ', N'
-Tetrakis (3-aminopropyl) ethylenediamine, N, N, N ', N'-tetrakis (3-hydroxypropyl) ethylenediamine, N, N, N', N'-tetrakis (2-dimethylaminoethyl) ethylenediamine, N , N, N ', N'-tetrakis (2-mercaptoethyl) ethylenediamine, N, N, N', N'-tetrakis (2-pyridylmethyl) ethylenediamine, N,
N, N ′, N′-tetrakis (2-pyridylethyl) ethylenediamine, N, N, N ′, N′-tetrakis (2
-Imidazolylmethyl) ethylenediamine, N, N,
N ′, N′-tetrakis (2-benzimidazolylmethyl) ethylenediamine, N, N, N ′, N′-tetrakis (2-oxazolylmethyl) ethylenediamine,
N, N ', N'-tetrakis (2-thiazolylmethyl)
Ethylenediamine, 1,2-bis [bis (2-hydroxyethyl) phosphino] ethane, 1,2-bis [6′-
Di (pyridi-2 "-yl) methylpyridi-2'-yl]
Examples thereof include ethane and the like, or anions and the like obtained by removing one or more protons from them.

In the transition metal complex catalyst of the present invention, the coordination atom is preferably a nitrogen atom or an oxygen atom.

The transition metal complex catalyst of the present invention is preferably a transition metal complex represented by the following general formula (III). (In the formula, M represents a transition metal atom of Groups 4 to 11, and R ³ to
R ^10's each independently represent a hydrogen atom, a hydrocarbon group, a substituted hydrocarbon group, a hydrocarbon oxy group, a substituted hydrocarbon oxy group, a disubstituted amino group, a nitro group or a halogen atom;
¹¹ represents a hydrogen atom, a hydrocarbon group or a substituted hydrocarbon group, R
¹² represents a bifunctional hydrocarbon group or a substituted hydrocarbon group which is substituted with any of R ^{7 to} R ¹⁰ of both rings. Y is a counter anion, y is the number of Y, and M
Is determined by the valence of. )

M, Y and y in the above general formula (III) are
It is the same as M, Y, and y in the general formula (I).

The hydrocarbon group in the above general formula (III) is preferably an alkyl group having 1 to 20 carbon atoms, an aralkyl group or an aryl group, specifically, a methyl group, an ethyl group, an n-propyl group or iso. -Propyl group, n-butyl group, iso-butyl group, t-butyl group, pentyl group,
Cyclopentyl, hexyl, cyclohexyl, octyl, decyl, benzyl, phenyl, naphthyl and the like.

The substituted hydrocarbon group in the above general formula (III) is a hydrocarbon group substituted with a halogen atom, an alkoxy group, an amino group, a disubstituted amino group or the like, and specific examples include a trifluoromethyl group, Examples thereof include a 2-t-butyloxyethyl group and a 3-diphenylaminopropyl group.

The hydrocarbon oxy group in the above general formula (III) is preferably an alkoxy group having 1 to 20 carbon atoms and an aryloxy group, specifically, a methoxy group, an ethoxy group, a propoxy group, a butoxy group and a hexyl group. Examples thereof include an oxy group, an octyloxy group, a phenoxy group and a naphthoxy group.

The substituted hydrocarbon oxy group in the above general formula (III) is a hydrocarbon oxy group substituted with a halogen atom, an alkoxy group, an amino group or the like, and specific examples include:
Examples include a trifluoromethoxy group, a 2-t-butyloxyethoxy group, and a 3-diphenylaminopropoxy group.

The disubstituted amino group in the above general formula (III) is preferably a disubstituted amino group having 1 to 20 carbon atoms, specifically, dimethylamino group, diethylamino group, dipropylamino group, dibutylamino group. Group, methylethylamino group, methylpropylamino group, methylbutylamino group, diphenylamino group, dinaphthylamino group and the like.

The halogen atom in the above general formula (III) is preferably a chlorine atom, a bromine atom or an iodine atom, and more preferably a chlorine atom or a bromine atom.

R ¹² in the above general formula (III) represents a bifunctional hydrocarbon group or a substituted hydrocarbon group which is substituted with any of R ^{7 to} R ¹⁰ of both rings. Examples of the bifunctional hydrocarbon group or substituted hydrocarbon group include a methylene group,
1,2-ethylene group, 1,2-propylene group, 1,3-
An alkylene group such as a propylene group or a 1,4-butylene group,
Examples thereof include a cycloalkylene group such as a 1,2-cyclopentylene group and a 1,2-cyclohexylene group, an arylene group such as a phenylene group, and a naphthylene group.

Transition metal complex represented by the above general formula (III)
Is preferably R^Three~ R^TenAre independently hydrogen sources
, A hydrocarbon group, a hydrocarbon oxy group, a nitro group or
Rogen atom, R¹¹Is a hydrogen atom or a hydrocarbon group
Yes, R¹²Is the R of both rings⁷Or R⁸Replaced
It is a functional hydrocarbon group. More preferably, R^Three~ R
^TenAre each independently a hydrogen atom, a methyl group, an ethyl group, n
-Propyl group, iso-propyl group, t-butyl group,
A phenyl group, a methoxy group, a nitro group, a chlorine atom, etc.,
R¹¹Is a hydrogen atom or a methyl group;¹²Is the R of both rings
⁷Substituted with 1,2-ethylene group, 1,3-propylene
And a 1,2-phenylene group.

In the transition metal complex of the present invention, the structure other than the ligand and the transition metal atom is not particularly limited as long as it does not deactivate the catalytic ability. In the transition metal complex catalyst of the present invention, a solvent or the like may be coordinated during the raw material of the complex, the synthesis process and / or the oxidative polymerization process.

The method for synthesizing the transition metal complex of the present invention includes, for example, a method of mixing a ligand compound with a transition metal compound in a suitable solvent. Examples of the transition metal compound include Bronsted acid salts of transition metals. As the transition metal complex, a complex synthesized in advance can be used, but the complex may be formed in a reaction system.

In the present invention, the catalysts can be used alone or as a mixture. In the present invention, the catalyst can be used in any amount, but generally, the amount of the transition metal compound is preferably 0.01 to 50 mol%, more preferably 0.02 to 10 mol%, based on the phenolic starting material. Is more preferred.

(2) Phenolic Starting Material In the present invention, a starting material represented by the following general formula (II) is used as the phenolic starting material. (In the formula, m represents the number average number of units and 1 <m.)

When the number average unit number m = 1, that is, when the polymerization is carried out only from phenol, it is possible to use, for example, Japanese Patent Publication No.
-18692 and Industrial Chemistry Magazine, Vol. 72, No. 10, 1
06 Even if a catalyst that hinders the reaction at the ortho position of phenol as proposed in (1969) is used, the resulting polymer contains a CC bond structure, has many ortho position branches, and the melting point is observed. And it becomes impossible to produce useful poly-1,4-phenylene ether.

Specific examples of the case where the number average unit number m is larger than 1 are 4-phenoxyphenol and 4-phenoxyphenol.
(4-phenoxyphenoxy) phenol, 4- {4-
(4-phenoxyphenoxy) phenolic compounds having an integer of 2 or more 1,4-phenylene ether structural units such as phenoxydiphenol; and mixtures of at least two or more compounds selected from these compounds and phenol. Commercially available 4-phenoxyphenol can be obtained, and other compounds can be obtained by known methods. For example, the method described in Tetrahedron, 23, 2253 (1967).

The number average unit number m is 1.01 ≦ m ≦ 6
Is preferable, and 1.05 ≦ n ≦ 2 is more preferable. More preferably, 4-phenoxyphenol is used as the phenolic starting material.

(3) Oxidative Polymerization In the present invention, any oxidizing agent may be used.
Preferably, oxygen or peroxide can be used. Oxygen may be a mixture with an inert gas or air. Examples of peroxides include hydrogen peroxide, t
-Butyl hydroperoxide, di-t-butyl peroxide, cumene hydroperoxide, dicumyl peroxide, peracetic acid, perbenzoic acid, and the like. Oxygen is more preferably used as the oxidizing agent.

In the present invention, the amount of the oxidizing agent used is not particularly limited, and when oxygen is used, it is usually used in an equivalent amount or a large excess relative to the phenolic starting material. When a peroxide is used, it is usually used in an amount of at least 3 equivalents, preferably at least 2 equivalents, based on the phenolic starting material.

The reaction of the present invention can be carried out in the absence of a reaction solvent, but it is generally desirable to use a solvent. The solvent is not particularly limited as long as it is inert to the phenolic starting material and liquid at the reaction temperature. Preferred examples of the solvent include aromatic hydrocarbons such as benzene, toluene and xylene; linear and cyclic aliphatic hydrocarbons such as heptane and cyclohexane; halogenated hydrocarbons such as chlorobenzene, dichlorobenzene and dichloromethane; acetonitrile , Nitriles such as benzonitrile; methanol, ethanol, n-
Alcohols such as propyl alcohol and iso-propyl alcohol; ethers such as dioxane, tetrahydrofuran and ethylene glycol dimethyl ether;
Amides such as N-dimethylformamide and N-methylpyrrolidone; nitro compounds such as nitromethane and nitrobenzene; and water. These are used alone or as a mixture.

When the solvent is used, the concentration of the phenolic starting material is preferably 0.5 to 50% by weight, more preferably 1 to 30% by weight.

When the transition metal complex has, as a counter ion, a conjugate base of an acid stronger than phenol, a base that does not inactivate the transition metal complex catalyst is made to coexist with the counter ion in an equivalent amount or more during polymerization. It is preferable. Examples of such bases are sodium hydroxide,
Hydroxides, oxides, alkoxides of alkali metals or alkaline earth metals such as potassium hydroxide, calcium oxide, sodium methoxide, sodium ethoxide; methylamine, ethylamine, propylamine, butylamine, dibutylamine, triethylamine, etc. Amines; pyridines such as pyridine, 2-methylpyridine, 2,6-dimethylpyridine, and 2,6-diphenylpyridine; Amines are commonly used,
Pyridines.

The reaction temperature for carrying out the present invention is not particularly limited as long as the reaction medium is in a liquid state. If no solvent is used, a temperature above the melting point of the phenolic starting material is required. A preferred temperature range is 0 ° C to 180 ° C, more preferably 0 ° C to 150 ° C.

[0042]

The present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited by these examples.

Conversion of Phenolic Starting Material (Conv.
): 15 mg of a reaction mixture containing diphenyl ether as an internal standard substance was sampled, acidified by adding a small amount of concentrated hydrochloric acid, and 2 g of methanol was added to obtain a measurement sample. This sample was subjected to high performance liquid chromatography (pump: 600E system manufactured by Waters, detector: UV / VIS-486 manufactured by Waters, detection wavelength: 278 nm, column: ODS-AM manufactured by YMC, developing solvent: methanol / water = Start at 50:50 and change to 100/0 after 25 minutes, then 45
Min) and diphenyl ether was quantified as an internal standard.

Infrared absorption spectrum analysis and peak area quantification of polymer: Measured using a Perkin Elmer 1600 infrared spectrophotometer (KBr method). The quantification of the peak area was performed using analysis software (GRAMS A manufactured by PerkinElmer).
nalyst 1600).

Polymer C—C bond structure amount (CC / CO):
Regarding the infrared absorption spectrum, the C—C bond structure peak area was set to an area of 996 to 1004 cm ⁻¹ , and the C—O bond structure peak area was calculated from the area of 996 to 1018 cm ⁻¹ .
The value was obtained by subtracting the peak area of the C-bond structure. As a measure of the amount of CC bond of the polymer, a value (CC / CO / CO bond structure peak area) determined by CC bond structure peak area / CO bond structure peak area
) Was used. In addition, when CC bond structure peak was not observed, it described as ND.

Ortho branching amount (o / p) of polymer: infrared absorption
As for the yield spectrum, the ortho-position branch peak area was 96
0-986cm ^-1Area. Ortho branching of polymers
As a guide of the amount, the ortho-position branch peak area / para-position connection
Use the value (o / p) determined from the peak area of the CO bond structure.
Was.

Polymer number average molecular weight (Mn), weight average molecular weight (Mw): Gel permeation chromatography (pump: Waters 600E system, detector: Waters UV / VIS-484, detection wavelength: 254 nm) , Column: Waters Ultrastyra
gel Linear = 2 + 1000A = 1 + 100A = 1
(Developing solvent: chloroform), and the weight average molecular weight (Mw) and the number average molecular weight (Mn) were measured in terms of standard polystyrene.

Melting point of polymer: Thermal analysis in a nitrogen atmosphere (DSC-50 manufactured by Shimadzu Corporation) was conducted at room temperature at 10 ° C./min to 3 ° C.
Raise the temperature to 00 ° C (1st scan), and then
The temperature was lowered from 00 ° C. to room temperature, and again from 10 ° C./min to 350 ° C. (2nd scan). In the 2nd scan, the peak temperature of the endothermic peak of 10 J / g or more at 100 ° C. or more was defined as the melting point.

Reference Example 1 (Synthesis of transition metal complex CuCu (hxpy)) i) ((6-methylpyrid-2-yl) di (2'-pyridyl) methan
e) Synthesis of [tripy]: A 500 mL three-necked flask was equipped with a reflux condenser and replaced with argon gas. Dry tetrahydrofuran (THF) 200 mL, 2,6-dimethylpyridine 21.4 g (0.2
mol) was added. After cooling to −78 ° C., 375 mL (0.6 mol) of 1.6 M n-BuLi was added with a syringe. The temperature was slowly returned to room temperature, heated to 35 ° C., and stirred for 3 hours. Cool again to -78 ° C, dry zinc chloride 90g (0.6g
Was dissolved in 100 mL of dry THF, and the temperature was returned to room temperature. The mixture was further heated to 60 ° C. and stirred for 3 hours. Once the temperature was returned to room temperature, 500 mg (0.43 mmol) of tetrakis (triphenylphosphine) palladium (0) and 100 g (0.63 mol) of 2-bromopyridine were added, and the mixture was heated to 70 ° C. and refluxed overnight. After stopping the reaction by adding 30 mL of water,
200 mL of a 3M sodium hydroxide aqueous solution was added, and the mixture was stirred for 30 minutes. Subsequently, 52 g (0.66 mol) of sodium sulfide and 150 mL of water
And zinc sulfide was precipitated. This was removed by Celite filtration, and the filtrate was extracted with chloroform.
(300 mL x 3). After the organic layer was dried over sodium sulfate (anhydrous), the solvent was distilled off under reduced pressure to obtain a black liquid. This was distilled under reduced pressure, and the residue was separated by column chromatography (filler; silica gel, developing solvent; chloroform-ethyl acetate-methanol) and recrystallized from hexane. (Yield 10.1g, Yield 20%)

Ii) (1,2-bis [6'-di (pyrid-2 "-rl) met
Synthesis of hylpyrid-2'-yl] ethane) [hxpy]: To a 200 mL three-necked flask, 100 mL of dry THF was added by a syringe, and tripy 1.0 g (3.9 mmol) was added under an argon atmosphere. This was cooled to -78 ° C, and 1.57M tert-BuLi was syringed.
8.7 mL (13.6 mmol) was added. The temperature was slowly returned to 0 ° C, and the mixture was stirred for 3 hours. 1.8 g (9.7 mmol) of 1,2-dibromoethane was added thereto, and stirring was continued at room temperature overnight. After the reaction was stopped by adding 10 mL of water, the solvent was distilled off under reduced pressure. 50 mL of water was added to the residue, extracted with chloroform (50 mL × 3), and the obtained organic layer was dried over sodium sulfate (anhydrous) and concentrated to obtain a reddish brown oily liquid. This was crystallized when dried under reduced pressure, and washed with ethyl ether to obtain flesh-colored powder crystals. (Yield 1.1g,
Yield 98%)

Iii) Synthesis of CuCu (hxpy): 272 mg (1.5 mmol) of copper (II) acetate hexahydrate was dissolved in 5 mL of methanol. When 260 mg (0.5 mmol) of Hexpy was dissolved in 5 mL of methanol and added, the solution turned from blue to dark green.
After stirring for 1 hour as it was, 516 mg (3 mmol) of sodium trifluoromethanesulfonate was added as a counter anion, whereby a blue precipitate was deposited. This was collected by filtration to obtain a complex having the following structural formula (hereinafter sometimes abbreviated as CuCu (hxpy)). (Yield 300mg, Yield 30%)

Example 1 A rubber balloon filled with oxygen was attached to a 25 ml two-necked round bottom flask equipped with a magnetic stirrer, and the inside of the flask was replaced with oxygen. CuCu (hxpy) 0.015 mmol was put into this, and 4-phenoxyphenol (4-PhOPhOH) 0.6m
mol and 2,6-diphenylpyridine as a base (Ph2P
y) 0.30 mmol dissolved in 1.2 g of toluene (PhMe) was added. While stirring the content, the flask was kept warm in a water bath at 40 ° C. for 22 hours. After the completion of the reaction, the mixture was acidified by adding a few drops of concentrated hydrochloric acid.
0 ml was added, and the precipitated polymer was collected by filtration. After washing three times with 10 ml of methanol and drying under reduced pressure at 100 ° C. for 5 hours, a white polymer was obtained. Table 1 shows the analysis results of the polymer.
The infrared absorption spectrum is shown in FIG.

Comparative Examples 1 to 3 Phenolic starting material, catalyst, base, solvent, reaction temperature,
A polymer was obtained in the same manner as in Example 1 except that the reaction time was changed as shown in Table 1. The results are shown in Table 1. FIG. 2 shows an infrared absorption spectrum of Comparative Example 1. In addition, PhOH
Represents phenol, CuCl represents cuprous chloride, Me2Py represents 2,6-dimethylpyridine, teed represents N, N, N ', N'-tetraethylethylenediamine, and PhNO2 represents nitrobenzene.

The polymer of Example 1 had a melting point at 184 ° C., but the polymers of Comparative Examples 1 to 3 had no melting point.

[0055]

[Table 1]

[0056]

As described above, according to the oxidative polymerization method using the specific phenolic starting material of the present invention and the catalyst of the present invention, there is no CC bond structure and no ortho-position branching. Low melting point, low color poly-
1,4-phenylene ether can be produced economically, and the industrial value of the present invention is extremely large. In addition, since the polymer obtained by this method has no CC bond structure, it is considered that there is no cross-linked structure, and improvement in mechanical properties and the like can be expected.

[Brief description of drawings]

FIG. 1 is an infrared absorption spectrum of the polymer of Example 1.

FIG. 2 is an infrared absorption spectrum of a polymer of Comparative Example 1.

Claims (6)

[Claims] 1. A transition metal complex represented by the following general formula (I):
Oxidize the raw material represented by the following structural formula (II) using a catalyst.
Poly-1,4-phenylene polymerized in the presence of an agent
Method for producing phenylene ether.(In the formula, M represents a transition metal atom of Groups 4 to 11, and R¹Is
Nitrogen atom, phosphorus atom, oxygen atom or sulfur as a coordinating atom
An organic group having atoms, all R¹Are the same but different
It may be. R¹Form a ring in any combination
May be. R ^TwoIs a nitrogen atom as a coordinating atom, phosphorus atom
A trifunctional organic group containing a child, an oxygen atom or a sulfur atom
Yes, all R^TwoMay be the same or different. Y
Is a counter anion, y is the number of Y,
It is determined by the valence of M. )(Where m represents the number average number of units, and 1 <m
You. ) 2. The number average unit number m is 1.01 ≦ m ≦ 6.
The poly-1,4- according to claim 1, wherein
A method for producing phenylene ether. 3. The poly-1,4- according to claim 1, wherein the oxidizing agent is oxygen or peroxide.
A method for producing phenylene ether. 4. The method for producing poly-1,4-phenylene ether according to claim 1, wherein the coordinating atom is a nitrogen atom and / or an oxygen atom. 5. The method for producing poly-1,4-phenylene ether according to claim 1, wherein the transition metal complex catalyst is represented by the following general formula (III). (In the formula, M represents a transition metal atom of Groups 4 to 11, and R ³ to
R ^10's each independently represent a hydrogen atom, a hydrocarbon group, a substituted hydrocarbon group, a hydrocarbon oxy group, a substituted hydrocarbon oxy group, a disubstituted amino group, a nitro group or a halogen atom;
¹¹ represents a hydrogen atom, a hydrocarbon group or a substituted hydrocarbon group, R
¹² represents a bifunctional hydrocarbon group or a substituted hydrocarbon group which is substituted with any of R ^{7 to} R ¹⁰ of both rings. Y is a counter anion, y is the number of Y, and M
Is determined by the valence of. ) 6. The method for producing poly-1,4-phenylene ether according to claim 1, wherein M is a transition metal atom of the first transition metal series.