Reverse polarity of amide nitrogen enables expedient access to N-cyano amides.

Abstract

N-Cyano amides are pivotal in agrochemicals, biologically active compounds, and nitrogen-containing heterocycles synthesis. Here, we present an umpolung cyanation strategy for the synthesis of N-cyano amides. By applying the readily accessible O-tosyl hydroxamates as nitrogen electrophiles, direct nucleophilic cyanation can be achieved with trimethylsilyl cyanide (TMSCN) under mild and transition metal-free conditions. This protocol features excellent functional group tolerance, easy scalability, and broad substrate scope (over 70 examples). Moreover, preliminary experimental studies and density functional theory (DFT) calculations support an S_N2-type mechanism of this reaction. Our work not only provides efficient, robust, and practical approaches to a variety of useful and complex N-cyano amide molecules but also expands the concept and scope of S_N2-type reaction at the non-anomeric amide electrophilic nitrogen center.