Rh(ii)-catalysed N2-selective arylation of benzotriazoles and indazoles using quinoid carbenes via 1,5-H shift

Abstract

An efficient Rh(II)-catalyzed highly selective N²-arylation of benzotriazole, indazole, and 1,2,3 triazole is developed using diazonaphthoquinone. The developed protocol is extended with a wide scope. In addition, late-stage arylation of these scaffolds tethered with bioactive molecules is explored. Control experiments and DFT calculations reveal that the reaction proceeds presumably via nucleophilic addition of the N² (of the 1H tautomer) center to quinoid-carbene followed by a 1,5-H shift.