Pd(OAc)2-Catalyzed Asymmetric Hydrogenation of α-Iminoesters

An efficient Pd(OAc)2-catalyzed asymmetric hydrogenation of α-iminoesters was realized for the first time at 1 atm hydrogen pressure and room temperature. Pd(OAc)2, a less expensive Pd salt with low toxicity, was found to be the most suitable catalyst precursor rather than Pd(TFA)2 which is usually the catalyst of choice for homogeneous asymmetric hydrogenation. The chiral α-arylglycine fragments are widely found in many chiral products and bioactive molecules.