Reductive transamidation of tertiary amides with nitroarenes enabled by magnesium and chlorosilane.

Reported here is the reductive transamidation of tertiary amides with nitroarenes promoted by main group metal magnesium and chlorosilane. The reaction uses commercially available and air-stable nitroarenes as nitrogen sources, so it can occur under transition-metal- and ligand-free conditions, thus providing a step-economic and cost-effective strategy for forming centrally important secondary amides. Several biologically interesting amide motifs are readily accessible by the Mg-promoted reductive transamidation.