The study of reaction mechanism for the transformation of nitronate into nitrile by phosphorus trichloride

Nitronate was generated using β-nitrostyrene and the anion of dimethyl malonate in THF at 0 °C. Subsequent treatment with PCl₃ in the presence/absence of DMAP either in THF or pyridine afforded nitroalkane, chloroxime, and nitrile. Pyridine, THF, and THF-pyridine co-solvent as solvents were investigated under different conditions. With different anions of malonates containing dipolarphiles, cyclic compounds were obtained as major products indicating nitrile oxides were generated during the reaction. Based on the results, compared to that of the one reported in literature, a plausible mechanism involving nitrile oxide intermediate was proposed.