Modular Assembly of Multisubstituted Furans and α-Alkylated Ketones via Photoactivation of Aniline-Linked Ternary Charge-Transfer Complexes.

Charge-transfer complexes such as electron donor-acceptor components have emerged as powerful platforms for visible-light-driven radical generation. While binary electron donor-acceptor systems have been extensively explored, the catalytic potential of higher-order multicomponent charge-transfer complexes remains largely underdeveloped. Here we report a distinct ternary charge-transfer complex formed by noncovalent interactions of α-bromo-substituted alkyl electrophiles, silyl enol ether, and o-phenylenediamine, which drives the formation of the α-carbon radical upon visible-light irradiation to establish a chain process. This transformation enables the efficient and modular construction of highly substituted furans and diverse α-alkylated ketones under mild conditions. These findings underscore the untapped potential of simple organic molecules to mediate photochemical transformations through an unconventional multicomponent charge-transfer process.