SELECTIVE ASYMMETRIC HYDROGENATION OF DEHYDROAMINO ACID DERIVATIVES USING RHODIUM AND IRIDIUM DIPHOSPHINITE CARBOHYDRATE CATALYST COMPOSITIONS

摘要

A process and catalyst composition are provided for the highly efficient enantioselective hydrogenation of dehydroamino acid derivatives. The catalyst composition comprises rhodium or iridium and a diphosphinite carbohydrate ligand, wherein the phosphorous atoms are attached to aromatic groups substituted with electron-donating substituents. Also provided is a means to selectively produce &agr; amino acids in either the L or the D form, based upon use of a sugar in the ligand with phosphinites attached in an absolute Right-Left or Left- Right configuration, respectively.