Patent ID: 6184421
Filing Date: 2001-02-06
Classification: C07C

Abstract:
A process for the preparation of a 4-hydroxybenzaldehyde and its derivatives, comprising the steps of:a) selectively oxidizing, to a carboxy group, the group in the 2 position with respect to the hydroxyl group, present in a starting mixture of phenolic compounds comprising at least:a phenolic compound (A) carrying formyl and/or hydroxymethyl groups in the 2 and 4 position;a phenolic group (B) carrying a formyl or hydroxymethyl group in the 4 position; anda phenolic compound (C) carrying a formyl or hydroxymethyl group in the 2 position;resulting in a mixture comprising a 3-carboxy-4-hydroxybenzaldehyde, a 4-hydroxybenzaldehyde and a 2-hydroxybenzoic acid,b) carrying out a decarboxylation operation on said resulting mixture obtained in step a) to produce the 4-hydroxybenzaldehyde and a phenol, andc) optionally, recycling the phenol obtained in step b).