Nanoscopic tin-oxygen linings on mesoporous silica as a novel catalyst fororganic hydrogen transfer reaction

Deposition of tin-oxygen species on mesoporous silica (MCM-41) was achieved via chemical reaction of SnEt4 vapour with surface silanol groups followed by heat treatment in air. Evidence suggested that highly reactive tin-oxyg en overlayers were formed on the internal surface of the MCM-41 silica, The se tin-oxygen modified silicas, after H-2 pre-treatment, showed excellent a ctivity in catalysing reduction of crotonaldehyde to crotyl alcohol using p ropan-2-ol as the hydrogen transfer agent (acetone was formed as the by-pro duct). It was also found that the catalytic activity per gram of tin increa sed dramatically as the tin loading decreased, The increase in the specific activity with the decrease in tin loading was attributed to the improved d ispersion of the tin-oxygen overlayers. (C) 2000 Elsevier Science B,V, All rights reserved.