Chemoselective Hydrogenation of α,β-Unsaturated Ketones Catalyzed by a Manganese(I) Hydride Complex.

Here, we report the chemoselective hydrogenation of α,β-unsaturated ketones catalyzed by a well-defined Mn(I) PC NHC P pincer complex [(PC NHC P)Mn(CO) 2 H] ( 1 ). The reaction is compatible with a wide variety of functional groups that include halides, esters, amides, nitriles, nitro, alkynes, and alkenes, and for most substrates occurs readily at ambient hydrogen pressure (1-2 bar). Mechanistic studies and deuterium labeling experiments reveal a non-cooperative mechanism, which is further discussed in this report.