Process for preparing aromatic polycarboxylic acids.

摘要

A process for preparing aromatic polycarboxylic acids comprises oxidising a benzil derivative with molecular oxygen in the presence of a Co or Mn oxidation catalyst and a bromine catalyst, in a solvent containing at least 50 wt% of an aliphatic monocarboxylic acid having up to 3 C atoms. 4,4 min -Bis(4-alkylphenyl)benzils (wherein alkyl is methyl, ethyl or isopropyl) are novel compounds.