Asymmetric hydrogenation catalyzed by CARAPHOS-rhodium
摘要:
The enantiomers of CARAPHOS, the aminophosphine phosphinite derivative of the beta-blocker Carazolol, have been prepared and investigated as Ligands in the rhodium catalyzed asymmetric hydrogenation of non-proteinogenic amino acid precursors. In comparison with the similar catalysts PROPRAPHOS and PINDOPHOS the observed optical yields in the range of 85-87% ee were lower by about 6-8%. The resolution of racemic Carazolol into its optical antipodes is described. (C) 1998 Elsevier Science B.V. All rights reserved.