Photocatalytic Dehydrogenative Cross‐Coupling of Alkenes with Alcohols or Azoles without External Oxidant

Direct cross‐coupling between alkenes/R‐H or alkenes/RXH is a dream reaction, especially without external oxidants. Inputting energy by photocatalysis and employing a cobalt catalyst as a two‐electron acceptor, a direct C−H/X−H cross‐coupling with H2 evolution has been achieved for C−O and C−N bond formation. A new radical alkenylation using alkene as the redox compound is presented. A wide range of aliphatic alcohols—even long chain alcohols—are tolerated well in this system, providing a new route to multi‐substituted enol ether derivatives using simple alkenes. Additionally, this protocol can also be used for N‐vinylazole synthesis. Mechanistic insights reveal that the cobalt catalyst oxidizes the photocatalyst to revive the photocatalytic cycle. Footloose and oxidant‐free: A photocatalytic process that employs a cobalt catalyst as an electron acceptor mediates direct C−H/X−H cross‐coupling and H2 evolution, achieving C−O and C−N bond formation.