Iodine-mediated regioselective C2-amination of indoles and a concise total synthesis of (±)-folicanthine

Highly substituted 2-aminated indoles can be prepared in moderate to excellent yields by regioselective C2-amination of indoles promoted by iodine. As a key step in a concise synthesis of (+/-)-folicanthine, its core structure was easily obtained by one step cyclization-dimerization of substituted tryptophan in high yield on a gram scale.