Efficient guanidine-catalyzed alkylation of indoles with fluoromethyl ketones in the presence of water.

A simple and efficient guanidine-catalyzed methodology for the direct preparation of trifluoromethyl-indolyl-phenylethanols in the presence of water is reported. This synthetically viable class of compounds is obtained in excellent yields (up to 98%) through Friedel-Crafts-type alkylation of indoles with aromatic fluoromethyl ketones. Exceptional reaction scope of indoles and alkylating agents is described.