Palladium-catalyzed asymmetric hydrogenolysis of N-sulfonyl aminoalcohols via achiral enesulfonamide intermediates

Abstract

Giving the cat complete control: A stereoconvergent formal hydrogenolysis of N-sulfonyl aminoalcohols in the presence of a chiral Pd catalyst and trifluoroacetic acid (TFA) gave chiral amines with two contiguous stereocenters (see scheme; TFE=trifluoroethanol, Ts=p-tosyl). The products were formed with up to 94 %ee by acid-catalyzed dehydration to afford an enesulfonamide, enamine/imine isomerization, and Pd-catalyzed asymmetric hydrogenation. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.