Asymmetric hydrogenation of unfunctionalized enamines catalyzed by iridium complexes of chiral spiro N,N-diarylphosphoramidites

Abstract

Chiral spiro N,N-diarylphosphoramidites were synthesized. These new chiral spiro monophosphoramidites were efficient ligands for iridium-catalyzed asymmetric hydrogenation of unfunctionalized enamines derived from simple alkyl aryl ketones, providing chiral tertiary amines in good enantioselectivities (up to 90% ee). © 2010 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.