Asymmetric induction in the inter- and intramolecular radical carbon-carbon bond forming reactions of N-arylsulfonyl-α-bromocarboxamides with chiral ligands:: the use of chiral sulfoxide ligands in radical chemistry

Inter- and intramolecular asymmetric radical carbon-carbon bond-forming reactions of sulfonamides were successfully achieved using chiral ligands in the presence of Lewis acids. The use of chiral sulfoxides as chiral ligands in the radical reactions of sulfonamides provided higher enantioselectivity, proceeding through a diastereomerically more favorable intermediate, presumably by enantiotopically selective coordination of one of the two oxygen atoms of the sulfonamides. (C) 2000 Elsevier Science Ltd. All rights reserved.