Palladium Catalysts Supported on Mesoporous Molecular Sieves Bearing Nitrogen Donor Groups: Preparation and Use in Heck and Suzuki C-C Bond-Forming Reactions

0326442 - ÚFCH JH 2010 RIV DE eng J - Journal Article
Demel, Jan - Lamač, M. - Čejka, Jiří - Štěpnička, P.
Palladium Catalysts Supported on Mesoporous Molecular Sieves Bearing Nitrogen Donor Groups: Preparation and Use in Heck and Suzuki C-C Bond-Forming Reactions.
[Palladiové katalyzátory zakotvené na mesoporézním molekulovém sítě nesoucím dusíkové donorové skupiny: příprava a použití v Heckově a Suzukiho reakci.]
ChemSusChem. Roč. 2, č. 5 (2009), s. 442-451. ISSN 1864-5631. E-ISSN 1864-564X
R&D Projects: GA MŠMT(CZ) LC06070; GA ČR GA104/09/0561
Institutional research plan: CEZ:AV0Z40400503
Keywords : supported catalysts * Heck reaction * mesoporous materials * palladium * Suzuki reaction
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 4.767, year: 2009

A series of supported catalysts is prepared by treatment of SBA-15-type mesoporous molecular sieve bearing SiCH2CH2CH2NHCH2CH2CH2NEt2 groups with palladium(II) acetate. These catalysts are studied in Suzuki biaryl couplings and in Heck reactions to establish the influence of metal loading and innocent surface modifications (trimethylsilylation). The Suzuki reaction proceeded efficiently with model and practically relevant substrates; the catalyst performance increasing with an increasing degree of metalation (decreasing N/Pd ratio). Catalyst poisoning tests revealed that the reaction takes place in the liquid phase with the catalyst serving as a reservoir of active metal species and also as a stabilizing support once the reaction is performed. In the Heck reactions, on the other hand, the catalyst performance strongly changed with the reaction temperature and with N/Pd ratio.

Série zakotvených katalyzátorů byla připravena nanesením SiCH2CH2CH2NHCH2CH2CH2NEt2 skupin na povrch SBA-15 a následnou modifikací octanem palladnatým. Byla zkoumána závislost množství zakotveného palladia na katalytických vlastnostech v Suzukiho a Heckově reakci.
Permanent Link: http://hdl.handle.net/11104/0173546