Silica-supported imine palladacycles - recyclable catalysts for the Suzuki reaction?

Bedford, R.B., Cazin, C.S.J., Hursthouse, M.B., Light, M.E., Pike, K.J. and Wimperis, S. (2001) Silica-supported imine palladacycles - recyclable catalysts for the Suzuki reaction? Journal of Organometallic Chemistry, 633(1-2), pp. 173-181.

Abstract

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: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Wimperis, Professor Stephen
• Authors: Bedford, R.B., Cazin, C.S.J., Hursthouse, M.B., Light, M.E., Pike, K.J., and Wimperis, S.
• Subjects: Q Science > QD Chemistry
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: Journal of Organometallic Chemistry
• ISSN: 0022-328X