Cobalt-Catalyzed Hydrogermylation of Nonactivated Alkenes Enabled by Photoirradiation

Metal-catalyzed hydrogermylation of alkenes provides a direct route to organogermanium compounds that exhibit diverse applications in organic synthesis, medicinal chemistry, and materials science. The reported reactions of the type, however, have been largely restricted to activated alkenes, and those of nonactivated alkenes remain rarely known. Herein, we report Co 2 (CO) 8 -catalyzed hydrogermylation of common aryl- and alkyl-substituted terminal alkenes with HGe n Bu 3 enabled by photoirradiation. The catalytic reaction delivers linear alkylgermanes in good to high yields with excellent regioselectivity. Mechanistic studies suggest a modified Chalk-Harrod mechanism for the catalytic reaction, in which photoirradiation drives the formation of coordinatively unsaturated germyl cobalt(I) intermediate.