Asymmetric hydrogenation of α-keto acid derivatives with Rh(I)-chiral diphosphinite system. Effect of halide counterion on the asymmetric induction

Article abstract of DOI:10.1246/bcsj.63.281

A chiral diphosphinite ligand having dicyclo-hexylphosphinooxy and dimethylamino moieties (Cy-POP-AE) was effective for the asymmetric hydrogenation of N-(benzoylformyl) amino acids by a Rh(I) catalyst under mild conditions. A neutral rhodium(I) precursor enabled a double asymmetric induction in methanol, while a cationic precursor caused an asymmetric induction controlled mainly by the substrate chirality.