The first highly enantioselective homogeneously catalyzed asymmetric reductive amination: synthesis of alpha-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 alpha-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.