Rhodium-Catalyzed C2-Alkylation of Indoles with Cyclopropanols Using ,-Dialkylcarbamoyl as a Traceless Directing Group.

An efficient rhodium-catalyzed synthesis of C2-alkylated NH-free indoles has been achieved from substituted indoles and cyclopropanols. The reaction allows the synthesis of various C2-alkylated products in good to excellent yield. Important features of the method include the use of a ,-dialkylcarbamoyl group as a traceless directing group, C-H/C-C bond functionalization, good functional group tolerance, broad scope, synthesis of pyrrolo[1,2-]indole, and identification of potential intermediates.