Exploring the Base‐Controlled Reactivity of Benzoyl Cyanide Toward Electrophilic Carbon Centers

ABSTRACT Benzoyl cyanide exhibits switchable reactivity toward an electrophilic carbon center governed by base strength, enabling its dual behaviour as a benzoylating/cyanating reagent. In the presence of a weak base, benzoyl cyanide functions as an efficient cyanobenzoylating reagent with aldehydes to deliver cyanohydrin esters, while with a strong base, benzoyl cyanide serves as a precursor to an acyl anion synthon, promoting C─C bond formation to deliver the desired α ‐acyloxy ketone products in good to excellent yields across a broad range of substrates. Notably, reactions with imines proceed selectively through cyanide transfer to afford α ‐aminonitrile. This study highlights the ambiphilic nature of the benzoyl cyanide, which establishes its versatile and base‐controlled strategy for switchable functionalization.