PREPARATION OF PARA NITROBENZOIC ACIDS AND 4{40 -NITRO-4-BIPHENYLCARBOXYLIC ACIDS

摘要

Preparation of p-nitrobenzoic and 4'-nitro-4-biphenylcarboxylic acids by contacting a p-sulfo benzoic acid or 4'-sulfo-4-biphenylcarboxylic acid with at least one molar proportion of nitric acid as a 5-60 percent by weight aqueous solution in the liquid phase at 120 DEG C.-300 DEG C. to displace the sulfo group by a nitro group and by contacting a benzenesulfonic acid or a 4-biphenyl sulfonic acid bearing an oxidizable alkyl group para to the sulfo group with aqueous nitric acid or a mixture of nitric acid and molecular oxygen containing gas at a temperature of 120 DEG -300 DEG C. in a single overall reaction.