Recent Progress on the Iterative Construction of 4-Substituited-3-Hydroxy Benzoic Acids from Unsaturated Aldehydes and Dimethyl Succinate

An improvement of a known two step cyclization procedure affording 4-aryl-3-hydroxy benzoic acid derivatives from 3-aryl-2,3-unsaturated aldehydes and dimethyl succinate is described. The high versatility of the synthetic procedure is shown as the aryl substituent can be a benzene or naphthalene moiety or an heteroaromatic ring. It can be applied iteratively to prepare p,p-oligophehyl derivatives.