Superacid counteranion as flexible-coordinating ligand for asymmetric organo-bismuth catalysis

Asymmetric binary catalysis combining chiral Brønsted acids with Lewis acids is currently limited to pre-organized, activated substrates. Here, the authors report binary catalysis combining an organosuperacid with bismuth, where the counteranion of chiral N-triflyl phosphoramide acts as a flexible-coordinating ligand for the asymmetric allylation of α-keto thioesters.