Phosphomolybdic acid-supported silica gel as efficient and cost-effective solid acid for the benzylation of indoles with benzylic alcohols

Indoles undergo smooth alkylation with benzylic alcohols on the surface of 10 mol% of phosphomolybdic acid supported on silica gel under mild conditions to produce C-3 benzylated-indoles in high yields and with high selectivity. This method offers significant advantages such as high conversions, short reaction times, mild reaction conditions, cleaner reaction profiles, high selectivity and low cost of the heterogeneous catalyst. (c) 2007 Elsevier B.V. All rights reserved.