Synthesis and characterization of new stabilized phosphorus ylides

New stabilized phosphoranes were obtained from the equimolar ratio of NH acids, dialkyl acetylenedicarboxylates and triphenylphosphine. The reaction was carried out in ethyl acetate at room temperature and accomplished after an hour. The reaction of ۵-methyl-۲-pyrolidone and N,N-dimethylacetamide with dimethyl acetylenedicarboxylate in the presence of triphenylphosphine led to the Z and E regioisomeric products, while the reaction of ۵-methyl-۲-pyrolidone with diethyl acetylenedicarboxyle provided the corresponding phosphorane as the sole poduct.