Cobalt‐Catalyzed Chemoselective Transfer Hydrogenation of C=C and C=O Bonds with Alkanols

Abstract An environmentally benign protocol of chemoselective transfer hydrogenation of C=C and C=O bonds with alkanols under base‐free conditions is developed by this study, wherein the cobalt‐ bidentate phosphine catalyst precursor is commercially available and the active low‐valent Co species could be generated in‐situ. For the conjugation enones, the vinyl group is selectively reduced, whereas with nonconjugated alkenones, the selectivity is changed to the carbonyl group. Besides, ortho ‐alkenyl‐benzaldehydes/imines are well tolerated, and the reduction solely occurs at the C=O/C=N site with this protocol.