PRODUCTION OF 4,4'-BIPHENYLDICARBOXYLIC ACID

摘要

PURPOSE:To produce the subject high-purity compound useful as a raw material of a polyester resin, a polyamide resin, etc., excellent in heat resistance and mechanical strength in a high yield by acetylating an economical and readily available 4-alkylbiphenyl and subsequently oxidizing the resultant acetylated compound. CONSTITUTION:An acetylation reaction is carried out between a 4-alkylbiphenyl and an acetyl halide or acetic anhydride in the presence of a friedel craft catalyst (e.g. aluminum trichloride anhydride) in a nonaqueous solvent (e.g. nitrobenzene) at 0-40 deg.C to obtain a 4-acetyl4'-alkylbiphenyl. The resultant compound is subsequently oxidized using molecular oxygen in the presence of an oxygenation catalyst containing a metallic compound of Mn, Co or Ni in a solvent containing >=25wt.% 1-3C fatty monocarboxylic acid (e.g. acetic acid) at 100-240 deg.C to obtain a 4,4'-biphenyldicarboxylic acid. Thus the objective compounds can be obtained by using ready operations while preventing generation of by-products.