Rhodium(i)-catalyzed N-arylation of arylazocarboxylates: facile access to unsymmetrical N,N-diarylhydrazides

A simple, efficient, and broad-scope rhodium(i)-catalyzed direct N-arylation of arylazocarboxylates with arylboronic acids has been developed, allowing access to a diverse range of unsymmetrical N,N-diarylhydrazides from readily available starting materials in high yields under extraordinary mild conditions. The reaction features easy operation, ambient temperature and low catalyst loading (as low as 0.1 mol%), as well as broad functional-group compatibility. The resulting N,N-diarylhydrazides could serve as versatile building blocks to furnish other structurally important or pharmaceutically interesting molecules. This protocol provides an attractive and complementary approach for the assembly of valuable N,N-diarylamine scaffolds.