An efficient zinc-catalyzed dehydration of primary amides to nitriles.

In the present study, the zinc-catalyzed dehydration of a variety of amides with N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) as a dehydration reagent into the corresponding nitriles has been examined in detail. With the straightforward and commercially available zinc(II)triflate as the precatalyst and MSTFA, an excellent system has been established to afford nitriles in excellent yields and chemoselectivities. After investigation of reaction conditions and the scope and limitations, several efforts were carried out to understand the reaction mechanism.