PROCESS AND INTERMEDIATES FOR PREPARING TICRYNAFEN

摘要

A Reimer-Tiemann reaction of 2,3-dichlorophenol with carbon tetrachloride gives 2,3-dichloro-4-hydroxy-benzoic acid, a novel intermediate, which is then reacted with thiophene in the presence of phosphorus pentoxide or polyphosphoric acid to give 2,3-dichloro-4-(2-thienoyl)-phenol. This compound is then converted to the diuretic, ticrynafen, by known prior art reactions.