Acylation of ferrocene: a new approach

Acylation of ferrocene by an acylating agent generated in situ from the corresponding carboxylic acid and phosphor-us trichloride, in the presence of the catalyst generated electrochemically from a sacrificial aluminum anode, was investigated. The corresponding monoacylferrocenes were obtained in very high yields when the molar ratio of reactants was ferrocene/carboxylic acid/PCl3 = 1: 1.2: 1, and by consumption 4.5 F/mol charge. The conditions for electrochemical diacylation of ferrocene were not found. However, acylation of ferrocene by the acylating agent generated in situ, but in the presence of commercial anhydrous aluminum trichloride as the catalyst, was successful in both monoacylation and diacylation processes. (C) 2002 Elsevier Science Ltd. All rights reserved.