RuV‐Acylimido Intermediate in [RuIV(Por)Cl2]‐Catalyzed C–N Bond Formation: Spectroscopic Characterization, Reactivity, and Catalytic Reactions

Abstract Metal‐catalyzed C−N bond formation reactions via acylnitrene transfer have recently attracted much attention, but direct detection of the proposed acylnitrenoid/acylimido M(NCOR) (R=aryl or alkyl) species in these reactions poses a formidable challenge. Herein, we report on Ru(NCOR) intermediates in C−N bond formation catalyzed by [Ru IV (Por)Cl 2 ]/N 3 COR, a catalytic method applicable to aziridine/oxazoline formation from alkenes, amination of substituted indoles, α‐amino ketone formation from silyl enol ethers, amination of C(sp 3 )−H bonds, and functionalization of natural products and carbohydrate derivatives (up to 99 % yield). Experimental studies, including HR‐ESI‐MS and EPR measurements, coupled with DFT calculations, lend evidence for the formulation of the Ru(NCOR) acylnitrenoids as a Ru V ‐imido species.