An efficient synthesis of phosphonate derivatives and stable phosphorus ylids by three-component reaction between phosphines or phosphites, benzil hydrazone and dialkyl acetylenedicarboxylates

Three-component reaction between trialkyl phosphites, dialkyl acetylenedicarboxylates and benzil hydrazone afforded phosphonate derivatives. Similar reaction between triphenylphosphine, dialkyl acetylenedicarboxylates and benzil hydrazone led to stable phosphorus ylides. When tri(n-octyl)phosphine was treated with dialkyl acetylenedicarboxylates and benzil hydrazone cyclic phosphorus ylide derivatives were obtained as the only product. All reactions were conducted in CH2Cl2 as solvent at room temperature without using any catalyst and the stable products were obtained in high yields.