Divergent Synthesis of Chiral-at-Sulfur Sulfoximines via Photoredox/Rhodium-Catalyzed Enantioselective C-H Activation.

Abstract

The merger of photoredox catalysis with transition-metal catalysis has emerged as a powerful platform for sustainable synthesis, yet asymmetric variants of photoinduced transition-metal-catalyzed C-H activation remain largely unexplored. Herein, we report a visible-light-driven Rh(III)/chiral carboxylic acid (CCA) cooperative catalytic system that enables the tunable divergent synthesis of two distinct classes of chiral sulfur-containing scaffolds from common sulfoximine and alkyne substrates. Through precise modulation of the reaction conditions, the reaction can be selectively steered toward either the annulation product or the ring-opened product with high enantioselectivities (up to 97% ee). This work provides the first example of asymmetric photoredox/group 9 CpXM(III)-catalyzed C-H functionalization and highlights reactive oxygen species as programmable selectivity switches in asymmetric catalysis.