Participation of an organosulfur functionality in asymmetric Pauson-Khand reactions using (S)-methionine-derived amides as enantiocontrollable substrates

An asymmetric Pauson-Khand reaction was successfully accomplished using chi ral phenylpropiolic carboxamides derived from (S)-methionine. Participation of the organosulfur functionality with cobalt catalysts in the asymmetric Pauson-Khand reaction is clearly demonstrated, giving the corresponding Pau son-Khand reaction products with extremely high diastereoselectivity in com parison to other substrates without similar sulfenyl groups. The absolute c onfiguration of the newly created chiral carbon centers was determined by X -ray crystallographic analysis. The mechanism for the asymmetric induction is proposed on the basis of the stereochemistry of the reactions determined by us. (C) 2000 Elsevier Science Ltd. All rights reserved.