Enantioselective hydrogenation of pyruvates over polymer-stabilized and supported platinum nanoclusters

✍ Scribed by Xiaobin Zuo; Hanfan Liu; Dawei Guo; Xiaozhen Yang

• Publisher: Elsevier Science
• Year: 1999
• Tongue: French
• Weight: 828 KB
• Volume: 55
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(99)00415-9

✦ Synopsis

The cinchonidine-modified enantioselective hydrogenation of pyruvates has been studied over polyvinylpyrrolidone-stabilized platinum (PVP-Pt) and the corresponding alumina-supported platinum (AI203-Pt) clusters. It is shown that the catalysts with particle size less than 2.0 um demonstrate >90% enantioselectivity in favor of (R)-lactates. The solvent effect is similar to that over the conventional supported platinum catalyst except for tetrahydrofuran. These colloidal and supported clusters are stable with no obvious loss of activity and enantioselectivity even after 18 months standing in air at room temperature. Molecular mechanics calculations of the modifier-reactant interaction on the platinum surface suggest that it is possible to obtain good enantioselectivity on the small clusters.