Alcohol Synthesis by Cobalt-Catalyzed Visible-Light-Driven Reductive Hydroformylation

A cobalt-catalyzed reductive hydroformylation of terminal and 1,1-disubstituted alkenes is described. One-carbon homologated alcohols were synthe-sized directly from CO and H2, affording anti-Markovnikov products (34–87% yield) with exclu-sive regiocontrol (linear/branch > 99:1) for mini-mally functionalized alkenes. Irradiation of the air-stable cobalt hydride, (dcype)Co(CO)2H (dcype = dicyclohexylphosphinoethane) with blue light gen-erated the active catalyst that mediates alkene hy-droformylation and subsequent aldehyde hydro-genation. Mechanistic origins of absolute regiocon-trol were investigated by in-situ monitoring of the tandem catalytic reaction using high-pressure mul-tinuclear NMR spectroscopy.