Ruthenium-catalyzed regioselective ring-opening of aliphatic and aryl epoxides under solvent-free conditions is reported. It was found that RUCl3 center dot nH(2)O catalyzes the Friedel-Crafts alkylation of indoles, providing 3-alkylated derivatives in good yields under mild reaction conditions. (c) 2008 Elsevier Ltd. All rights reserved.