A Direct Cycloaminative Approach to Imidazole Derivatives via Dual C-H Functionalization.

Organoiodine(III)-promoted C(sp3)-H azidation was a key step for the cycloaminative process. An unprecedented method for metal-free dehydrogenative N-incorporation into C(sp3)-H and C(sp2)-H bonds for the synthesis of diverse imidazoles has been disclosed. The overall transformation involves the construction of four C-N bonds through hydroamination-azidation-cyclization sequence. The reaction can be easily handled and proceeds under mild conditions. Further, the potential of the present strategy is revealed by the practical synthesis of N-heterocyclic carbene (NHC) precursors.