N-Heterocyclic carbene-catalyzed radical ring-opening acylation of oxime esters with aldehydes

A cross-coupling of cycloketone oxime esters with aldehydes catalyzed by N-heterocyclic carbenes via a radical pathway was established. This modular protocol features easy operation, no external oxidants or reductants, and a broad functional group compatibility. The merit of this method was showcased by late-stage modification of complicated aldehydes derived from the medical intermediate pregnenolone and natural product diacetone-D-glucose.