Photoinduced Enantioselective C-H Bond Arylation of Carbonyls via Aryl Thianthrenium Salts

The enantioselective arylation of carbonyl compounds is a powerful yet demanding transformation with broad applications in pharmaceutical and agrochemical discovery. Current methods typically require prefunctionalised aryl reagents and costly chiral metal complexes, limiting both scope and sustainability. This project proposes a multicatalytic platform that combines visible-light-driven Cu-catalysed decarboxylation of aryl carboxylic acids to generate aryl thianthrenium salts in situ with chiral amine catalysis via electron donor–acceptor (EDA) complex activation. This strategy employs abundant carboxylic acids as renewable aryl sources, releases only CO2 as a by-product, and delivers high enantioselectivity under mild conditions. Mechanistic investigations will probe radical intermediates and the role of EDA complexes in asymmetric bond formation, providing fundamental insights into multicatalytic photochemical systems. The methodology will enable direct α- and γ-functionalisation of carbonyl compounds, streamline access to enantioenriched scaffolds, and expand the synthetic utility of carboxylic acids as sustainable building blocks.