Cobalt-Catalyzed Chemoselective Reduction of -Heteroaryl Ketones with ,-Dimethylformamide as a Hydride Source.

A method for chemoselective reduction of 2-pyridyl ketones and related -heteroaryl compounds catalyzed by cobalt stearate using DMF as a hydride source is developed. The ketone substrate is activated by chelation with cobalt, which makes the present method highly chemoselective. A possible reaction mechanism is proposed on the basis of control experiments.