The combinatorial synthesis of chiral phosphine ligands

Chemistry is reported that allows for the synthesis and screening of phosphine ligands by standard combinatorial technology. To demonstrate the method a 63 member library of phosphine containing peptides was synthesized. Rhodium was complexed to the phosphine ligands while they were attached to the synthesis support. Each member of the library was screened for its ability to catalyze the asymmetric hydrogenation of enamide (3). Some correlation between specific substitutions in the primary sequence of the peptide and the highest enantiomeric excesses was observed. Copyright (C) 1996 Elsevier Science Ltd