JPS621614B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing polyarylene vinylene. Since polyarylene vinylene is a conjugated aromatic polymer containing carbon-carbon double bonds, it is well known that it has useful properties such as heat resistance, electrical conductivity, and optical properties, and various attempts have been made to synthesize this material. being done. For example, (1) the use of the Wittig reaction, that is, the condensation reaction of bisphosphorane and dialdehyde; (2) Utilization of the Knoevenagel reaction, that is, the direct condensation reaction of active methyl groups with aldehydes H ₃ C−Ar−CH ₃ +OHC−Ar′−CHO→(−Ar−CH=CH−Ar′− CH=CH-) _o (3) Utilization of dehydrohalogenation reaction in which various strong bases (t-BuOK, NaNH ₂ , NaH, etc.) act on bishalomethylarylene compounds X-CH ₂ -Ar-CH ₂ Methods such as -X→(-Ar-CH=CH-) _o are known. These methods are excellent and have high practical value; however, the use of the Wittzig reaction in (1), for example, requires the use of substituents that react with the ylide, such as amino groups, carbonyl groups, and hydroxyl groups. However, since the product is a mixture of cis and trans isomers, cis-to-trans isomerization is needed to improve oxidation stability, softening point, electrical conductivity, etc. is necessary. In the Knebenagel reaction (2), the reaction does not proceed unless the methyl group is activated by an electron-withdrawing group such as a nitro group or an amino group, and the range of raw materials is limited. In the dehydrohalogenation reaction (3), since the polymer contains an active halomethyl group, the selection of raw materials is limited because the polymer cannot contain an amino group or the like that reacts with the active halomethyl group. Each of them has drawbacks. Therefore, the present inventors conducted various studies for the purpose of solving the problems in the reaction of polyarylene vinylene and finding an excellent manufacturing method. As a result, we have discovered a new method for producing polyarylene vinylene that can be easily produced with good yield. The method for producing polyarylene vinylene of the present invention has the general formula

By reacting a halobinylarylene compound represented by the formula in the presence of a catalyst consisting of a combination of palladium acetate and triarylphosphine and a hydrogen halide scavenger,

The object of the present invention is to easily produce polyarylene vinylene represented by the formula in good yield. (However, Ar is

【formula】

[Formula], R ¹ and R ² are each selected from hydrogen and an alkyl group, X is selected from bromine or iodine, and n is the degree of polymerization of 2 to 50.
is an integer. ) This reaction typically requires a catalyst and a hydrogen halide scavenger. As a catalyst, a combination of a noble metal compound such as palladium acetate and a phosphorus compound such as triarylphosphine is suitable. Suitable hydrogen halide scavengers include amines such as secondary amines and tertiary amines, and basic salts such as sodium bicarbonate and sodium carbonate. General formulas that can be used in the present invention

Some specific examples of halobinylarylene compounds represented by the formula: 4-bromustyrene, 4-iodostyrene, 3-bromustyrene, 2-bromo-4
-vinylthiophene, 4-bromo-α-methylstyrene, 4-bromo-β-methylstyrene, and the like and mixtures thereof. The method of the invention is based on the general formula

It is carried out by reacting a halobinylarylene compound represented by the formula at a temperature of 75°C to 150°C in the presence of, for example, palladium acetate, triarylphosphine, and a tertiary amine, and this reaction is carried out for 1 hour to 50 hours. It is completed with. Triarylphosphines include triphenylphosphine, tri-O-tolylphosphine, tris(2,5-diisopropylphenyl)phosphine, tri-α-naphthylphosphine, tris(2,3,4,5- Tetramethylphenyl)phosphine, tris(2-methyl-5-t-butyl)
Examples include phosphine, tris(P-carbomethoxyphenyl)phosphine, and the use of tri-O-tolylphosphine and tris(2-methyl-5-t-butylphenyl)phosphine is particularly preferred. The triarylphosphine used in the present invention is 0.5 to 1 mole of palladium acetate.
~10 mol is suitable. In addition, the amount of palladium acetate used is 0.5 to 4 of the amount of halobinylarylene used.
Mol% is appropriate. Tertiary amines are used as scavengers for generated hydrogen halides, and common amines such as triethylamine, tri-n-butylamine, triamylamine, and tetramethylethylenediamine can be used, and the amount used depends on the amount of generated halogens. It is usually used in a slight molar excess relative to hydrogen hydride. As the reaction solvent, common ones such as N.N-dimethylformamide, dimethylacetamide, toluene, xylene, chlorobenzene,
O-dichlorobenzene, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, dimethyl sulfoxide, acetonitrile, etc. are used. Both terminal groups of the polymer obtained according to the present invention are usually hydrogen, bromine or iodine, and especially the terminal group on the vinyl group side is usually hydrogen. The polymers are generally thermoplastics of excellent high temperature stability, and depending on the reactants chosen, some are soluble in solvents and can also be formed into films by casting processes. The method of the present invention has a wider range of usable compounds than conventional methods, and by utilizing this reaction,
It is also possible to produce polymers that were previously impossible to produce. The polymer produced by the method of the present invention has useful properties such as heat resistance, electrical conductivity, and optical properties like polymers produced by other methods, and can be used for any purpose. I can do it. EXAMPLES The present invention will be specifically explained below using Examples, but the present invention is not limited to these Examples. Example 1 1.83 parts of P-bromostyrene (parts by weight, same below), 1.95 parts of tri-n-butylamine, 0.022 parts of palladium acetate, tri-O-tolylphosphine
A mixture of 0.122 part of
Allowed time to react. The solid content was precipitated by pouring the reaction mixture into methanol. The obtained solid content was washed with methanol and toluene and dried to obtain 1.06 parts of a yellow polymer. According to the infrared absorption spectrum, CH out-of-plane bending absorption δCH (t-CH=
Absorption based on CH) is seen at 956 cm ^-1 . The degree of polymerization n was determined by the terminal bromine quantitative method.
It was 12. An infrared absorption spectrum diagram is shown in FIG. Examples 2 to 4 Polymerization was carried out in accordance with the method of Example 1, except that the following halobinylarylene was used in place of P-bromostyrene. Examples are shown in the table below.

【table】 [Brief explanation of the drawing]

FIG. 1 shows an infrared absorption spectrum of the polymer of the present invention produced in Example 1.

Claims (1)

[Scope of Claims] 1. A halobinylarylene compound represented by the general formula [Formula] is reacted in the presence of a catalyst consisting of a combination of palladium acetate and triarylphosphine and a hydrogen halide scavenger, A method for producing polyarylene vinylene represented by the general formula [Formula]. (However, Ar is represented by [Formula] [Formula], R ¹ and R ² are each selected from hydrogen or an alkyl group, and X is selected from bromine or iodine, n is the degree of polymerization, 2 to 50
is an integer. 2 The hydrogen halide scavenger is a secondary amine or 3
2. The method according to claim 1, wherein the amine is a grade amine.