Photoredox/Cobalt Dual Catalysis for Visible-Light-Mediated Alkene-Alkyne Coupling

Dual photoredox transition-metal catalysis has recently emerged as a powerful tool for making synthetically challenging carbon-carbon bonds under milder reaction conditions. Herein, we report on the visible-light-mediated controlled generation of low-valent cobalt catalyst without the need for a metallic reductant. It enabled C-C bond formation via ene-yne coupling at room temperature. The generality of this dual catalysis is demonstrated via the creation of sizable molecular diversity with the accommodation of several functional groups.