Silica-supported imine palladacycles—recyclable catalysts for the Suzuki reaction?
Bedford, Robin B., Cazin, Catherine Catherine Suzanne Julienne, Hursthouse, Michael B., Light, Mark E., Pike, Kevin J. and Wimperis, Stephen. (2001) Silica-supported imine palladacycles—recyclable catalysts for the Suzuki reaction? Journal of Organometallic Chemistry, Vol.633 (No.1-2). pp. 173-181. ISSN 0022328XFull text not available from this repository.
Official URL: http://dx.doi.org/10.1016/S0022-328X(01)01080-4
Silica-supported, imine-based palladacyclic catalysts have been synthesised and the crystal structure of complex 9, the triphenylphosphine adduct of the pre-supported precursor complex 8, has been determined. The solid-supported catalysts show considerably lower activity in the Suzuki reaction than their homogeneous counterparts. Poor recyclability of the silica-immobilised catalysts and the presence of active catalysts in solution indicate that imine-based palladacyclic catalysts are unstable with respect to liberation of zero-valent palladium species. Whilst the solid-supported complexes are not useful as catalysts, they do function as excellent mechanistic probes. Studies on model complexes give further information on the processes that cause the liberation of zero-valent species not only from the solid-supported catalysts, but also from homogeneous systems. In all cases it appears that a reductive-elimination event occurs to generate the active catalyst.
|Item Type:||Journal Article|
|Subjects:||Q Science > QD Chemistry|
|Divisions:||Faculty of Science > Physics|
|Library of Congress Subject Headings (LCSH):||Catalysis, Silica, Organometallic chemistry, Organic reaction mechanisms, Palladium catalysts|
|Journal or Publication Title:||Journal of Organometallic Chemistry|
|Official Date:||August 2001|
|Page Range:||pp. 173-181|
|Funder:||Engineering and Physical Sciences Research Council (EPSRC)|
|Grant number:||GR/M12209 (EPSRC)|
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