| 摘要 |
NEW MATERIAL:m-Terphenyl-3,4,3'',4''-tetracarboxylic acid expressed by formula I or dianhydride thereof expressed by formula II. USE:A raw material for excellent heat-resistant polyimide resins, etc., curing agent, etc., for epoxy resins, phenolic resins, etc. PREPARATION:A 4-halogeno-o-xylene is reacted with metallic Mg and is Cl, Br or I), which is then subjected to double cross coupling reaction with an m-dihalogenobenzene expressed by formula IV (X2 is same as X1) in the presence of a nickel metal complex catalyst, e.g. dichloro[1,2-bis(diphenylphosphino) ethane]nickel, etc., to afford a compound expressed by formula V. The resultant compound expressed by formula V is then oxidized with a permanganate, nitric acid or air in the liquid phase to provide the compound expressed by formula I, which is cyclodehydrated while heating or with acetic anhydride or directly oxidized in the vapor phase to give the compound expressed by formula II.
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