Synthesis of α,β-Unsaturated Aldehydes through Palladium Catalyzed Regioselective Hydrogen Migration
Treatment of cyclic carbonate of 3-alkene-1,2-diols or 4-methylcarbonate of 2-alkene-1,4-diols with a catalytic amount of Pd(PPh3)4 in aqueous THF or AcOH gave α,β-unsaturated aldehydes in good yields.The reaction can be interpreted by the regioselective 1,4-hyrogen migration of ?-allylpalladium intermediate.