Study of the Chemoselectivity of Grignard Reagent Addition to Substrates Containing Both Nitrile and Weinreb Amide Functionalities

Abstract Several substrates containing both cyano and Weinreb amide functionalities have been synthesized to study the chemoselectivity of their reactions with organomagnesium bromides (ArMgBr and RMgBr). Excellent chemoselectivity towards the Weinreb amide was observed in most cases, even in the presence of excess Grignard reagent, affording cyano ketones in good‐to‐excellent yields.