METHOD FOR PREPARING OXYDIPHTHALIC ANHYDRIDES USING BICARBONATE AS CATALYST

摘要

Oxydiphthalic anhydrides such as 4-oxydiphthalic anhydride are prepared by the reaction of a halophthalic anhydride with an alkali metal carbonate such as potassium carbonate in the presence of a catalyst system comprising an alkali metal bicarbonate such as potassium bicarbonate and a phase transfer catalyst, preferably a tetraarylphosphonium halide.