The first highly enantioselective homogeneously catalyzed asymmetric reductive amination:: Synthesis of α-N-benzylamino acids

High-throughput screening considering a library of 96 chiral P-ligands involved in two types of Rh-I complexes was used for the identification of homogeneous catalysts for the highly enantioselective reductive amination of a-keto acids with benzylamine. After optimization of the reaction conditions and scale-up with a cationic Rh-Deguphos catalyst, a range of chiral alpha-amino acids could be produced by this new reaction in good yield and by up to 98% ee.