VERFAHREN ZUR HERSTELLUNG VON PROTOCATECHUALDEHYD UND DESSEN DERIVATEN

摘要

A process for preparing protocatechualdehyde or a 3-alkoxy-4-hydroxybenzaldehyde which comprises subjecting catechol or a 2-alkoxyphenol to reaction with glyoxylic acid in a basic aqueous medium in the presence of a catalyst containing one or more compounds selected from aluminium oxide, silicon oxide and hydrated aluminium oxide in an amount of not less than 0.01 g per 1 g of the starting catechol or 2-alkoxyphenol at a temperature of 0 DEG to 50 DEG C., and then oxidizing the thus obtained reaction mixture in a basic medium.