A facile one pot synthesis of bisphosphonic acids and their sodium salts from nitriles

Abstract

A general and one pot synthesis for the preparation of bisphosphonic acids and their sodium salts (2a-e) from nitriles (3a-e) is described. This method involves hydrolysis of nitriles (3a-e) to the corresponding acids and subsequent bisphosphonation in a single solvent to produce bisphonates (2a-e). Preparations of some of bisphosphonates, which are presently in clinical use like risedronate (2a) sodium, ibandronate sodium (2d) are synthesized by following this new method. This method is useful for the preparation of other bisphosphonate compounds.