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

ABSTRACT: Asymmetric binary catalysis, particularly combining chiral Brønsted acids with Lewis acids, is an emerging strategy in synthetic chemistry. Although a few catalyst combinations exist for stereoselective transformations, their scope is generally limited to pre-organized, activated substrates. Here, we report binary catalysis combining an organosuperacid with bismuth, where the counteranion of chiral N-triflyl phosphoramide acts as a flexible-coordinating ligand. This system demonstrates exceptional reactivity and enantioselectivity in the asymmetric allylation of α-keto thioesters, forming enantio-enriched α-hydroxy thioesters with a tetra-substituted stereogenic carbon center (up to > 99% yield and 97% ee). The success is attributed to bismuth's flexibility during activation, enhancing als

SUBMITTER: Park JH 

PROVIDER: S-EPMC12222474 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature