Photoinduced, Copper-Catalyzed Three-Component Annulation of <i>gem</i>-Dialkylthio Enynes
Jiang Lou, Juan Ma, Bao‐Hua Xu, Yong‐Gui Zhou, Zhengkun Yu
Abstract
Photoinduced, copper-catalyzed three-component radical annulation of gem-dialkylthio enynes, cyclobutanone oxime esters, and boronic acids was achieved, forming highly functionalized aryl thienyl sulfides with both good chemo- and diastereoselectivities. The reaction proceeds through a domino sequence involving cyanoalkyl radical-mediated intramolecular annulation of gem-dialkylthio enyne, alkenyl radical-promoted C(sp3)–S bond cleavage, and sulfur-centered radical-trapped Cu(II)-facilitated C–S cross-coupling. The protocol features simultaneous establishment of cyanoalkyl, cyclopentanone, and thiophene moieties and a thioether C–S bond in one pot with broad substrate scopes and versatile functional group tolerance under mild conditions.