Light mediated asymmetric approaches towards alkene difunctionalization

Abstract

Visible-light photochemistry has emerged as a powerful platform for the development of asymmetric radical transformations under mild and sustainable conditions. Particularly, the enantioselective difunctionalization of alkenes enables the rapid construction of molecular complexity through the simultaneous formation of two bonds across the C=C bond, providing rapid access to highly functionalized optically active organic skeletons. Despite the remarkable progress achieved in racemic variants, asymmetric light-driven processes remain comparatively underexplored due to the challenges associated with stereocontrol in open-shell pathways. This review highlights recent advances in light-mediated asymmetric alkene difunctionalization, with particular emphasis on the strategies that enable efficient enantiocontrol. The discussion is organized according to the mode of stereochemical induction, including metallaphotoredox dual catalysis, cooperative photoredox catalysis combined with chiral hydrogen-bonding catalysts, and the use of enantioenriched reagents as traceless chiral auxiliaries. Special attention is given to mechanistic features that govern radical generation, metal-radical interception and enantiodetermining bond-forming scenarios. By providing a unified overview of these complementary approaches, this review outlines the current state of the art and future opportunities for the development of general, efficient and sustainable asymmetric multicomponent reactions driven by visible light.