Base-Catalyzed Bifunctional Addition to Amides and Imides at Low Temperature. A New Pathway for Carbonyl Hydrogenation

Mono- or dideprotonation at the N–H groups of the Noyori ketone hydrogenation catalyst trans-[RuH₂((R)-BINAP)­((R,R)-dpen)] (1a) yields trans-M­[RuH₂((R,R)-HNCH(Ph)CH(Ph)NH₂)­((R)-BINAP)], where M = K⁺ (8-K) or Li⁺ (8-Li), or trans-M₂[RuH₂((R,R)-HNCH(Ph)CH(Ph)NH)­((R)-BINAP)], where M = Li⁺ (8-M′₂), which have unprecedented activity toward the hydrogenation of amide and imide carbonyls at low temperatures in THF-d₈. Details of the origins of the enantioselection for the desymmetrization of meso-cyclic imides by hydrogenation with 8-K are also described herein.