Visible‐Light‐Promoted Electron Donor–Acceptor‐Induced Coupling Reaction of Ketyl Radicals With Alkane

A visible‐light‐promoted electron donor–acceptor (EDA) complex‐enabled generation of ketyl radicals from aryl aldehydes and their coupling reaction is reported. This mild, photocatalyst‐ and transition metal‐free protocol provides direct access to a variety of α,β‐unsaturated compounds in moderate to excellent yields. Mechanistic studies support the formation of a key EDA complex between the aldehyde and the in situ generated enolate from DMA and t BuONa, with radical coupling as the pivotal step. This work expands the scope of EDA‐mediated ketyl radical chemistry under mild conditions.