Efficient aziridination of olefins catalyzed by mixed-valent dirhodium(II,III) caprolactamate

摘要

A mild, efficient, and selective aziridination of olefins catalyzed by dirhodium(II) caprolactamate [Rh-2(cap)(4)center dot 2CH(3)CN] is described. Use of p-toluenesulfonamide (TsNH2), N-bromosuccinimide (NBS), and potassium carbonate readily affords aziridines in isolated yields of up to 95% under extremely mild conditions with as little as 0.01 mol% Rh-2(cap)(4). Aziridine formation occurs through Rh-2(5+)-catalyzed aminobromination and subsequent base-induced ring closure. An X-ray crystal structure of a Rh-2(5+) halide complex, formed from the reaction between Rh-2(cap)(4) and N-chlorosuccinimide, has been obtained.