Synthesis of 3-Indolyl-substituted Benzoboroxole via Friedel-Crafts Reaction in Water

A highly efficient and catalyst free approach for the synthesis of 3-indolyl-substituted benzoboroxole via Friedel-Crafts reaction in water was developed successfully using readily accessible 2-formylbenzeneboronic acid and indole as the starting material and water as solvent at room temperature. An array of desired 3-indolyl-substituted benzoboroxoles was synthesized in moderate to near quantitative yield.