Manganese‐Catalyzed Chemoselective Direct Hydrogenation of α,β‐Epoxy Ketones and α‐Ketoamides at Room Temperature

Abstract Chemoselective hydrogenation of α , β ‐epoxy ketones and α ‐ketoamides is achieved at room temperature (25 °C) using 2.0 bar H 2 and a pincer‐ligated Mn(I) catalyst that provides synthetically valuable α ‐hydroxy epoxides and α ‐hydroxy amides. This protocol applies to a wide range of alkyl‐ and aryl‐substituted α , β ‐epoxy ketones, including terpenes ( α ‐ionone, nootkatone, and R ‐carvone)‐ and steroids (testosterone and progesterone)‐derived epoxy ketones, and tolerates H 2 sensitive functionalities, such as halides, acetyl, nitrile, nitro, epoxide, alkenyl and alkynyl groups. Additionally, α ‐ketoamides bearing reducible functional groups, including acetyl and diazo benzene, were untouched under this protocol and selectively converted to α ‐hydroxy amides. A preliminary mechanistic study highlighted the metal‐ligand cooperative H 2 activation process.