Process for preparing substituted aromatic and heteroaromatic aldehydes and carboxylic acids

摘要

A process for preparing substituted aromatic and heteroaromatic aldehydes or carboxylic acids of the formulain which R1 and R2 are H, C1-C4 alkyl, C1-C4 alkoxy, OH, NO2, CN, COOH, CONH2, COOR, NH2, SO3H or halogen and R is C1-C4 alkyl and where R1 and R2 are not simultaneously H, X is C or N and Z is CHO or COOH, from the corresponding symmetric stilbene compounds of the formulain which R1, R2 and X are as defined above, by aqueous ozonolysis and subsequent isolation of an aldehyde or oxidation to give the corresponding carboxylic acid.