MCM-41-supported platinum carbonyl cluster-derived catalysts for asymmetric and nonasymmetric hydrogenation reactions

TitleMCM-41-supported platinum carbonyl cluster-derived catalysts for asymmetric and nonasymmetric hydrogenation reactions
Publication TypeJournal Article
Year of Publication2006
AuthorsBasu, S, Mapa, M, Gopinath, CS, Doble, M, Bhaduri, S, Lahiri, GKumar
JournalJournal of Catalysis
Volume239
Issue1
Pagination154-161
Date PublishedAPR
Type of ArticleArticle
ISSN0021-9517
Keywordsasymmetric/non-asymmetric catalysis, Enantioselectivity, functionalized MCM-41, hydrogenation catalysts, platinum carbonyl cluster
Abstract

Anionic platinum carbonyl Cluster ([Pt-12(CO)(24)](2-)) was ion-paired with the 3-chloropropyltrimethoxysilyl-ammonium group chemically bound to the surface of MCM-41. The materials undergo quick decarbonylation and have been characterized before decarbonylation by IR and UV-vis spectroscopy and after decarbonylation by XPS and TEM. They have been used as catalysts for the hydrogenations of methyl pyruvate, acetophenone, nitrobenzene, benzonitrile, and ethylacetoacetate. The support and the quaternary ammonium groups have significant effects on surface platinum concentration, crystallite size, and observed activity. In the hydrogenation of the prochiral substrates methyl pyruvate or acetophenone, the cinchonidine-based catalyst gives significant enantioselectivity under optimum conditions. A kinetic model that includes an enantioselective product-formation step and a hydrogen pressure-dependent step for the deactivation of the enantioselective sites gives reasonable agreement between predicted and observed enantioselectivity. The model is also in accordance with the XPS and TEM data. (c) 2006 Elsevier Inc. All rights reserved.

DOI10.1016/j.jcat.2006.01.032
Type of Journal (Indian or Foreign)

Foreign

Impact Factor (IF)

7.354

Divison category: 
Catalysis and Inorganic Chemistry