Oxidant-Switchable Selective Synthesis of 2‑Aminobenzimidazoles via C–H Amination/Acetoxylation of Guanidines

The iodine­(III) compound promoted C–H amination and tandem C–H amination/acetoxylation of guanidines are achieved for the first time to provide efficiently 2-aminobenzimidazoles and acetoxyl-substituted 2-aminobenzimidazoles, respectively. The amount and type of iodine­(III) compounds control the selective syntheses of two types of 2-aminobenzimidazoles. This reaction shows good regioselectivity when unsymmetrical substrates are used.