Ru-Based Complexes with Quaternary Ammonium Tags Immobilized on Mesoporous Silica as Olefin Metathesis Catalysts

0431081 - ÚFCH JH 2015 RIV US eng J - Journal Article
Pastva, Jakub - Skowerski, K. - Czarnocki, S. J. - Žilková, Naděžda - Čejka, Jiří - Bastl, Zdeněk - Balcar, Hynek
Ru-Based Complexes with Quaternary Ammonium Tags Immobilized on Mesoporous Silica as Olefin Metathesis Catalysts.
ACS Catalysis. Roč. 4, č. 9 (2014), s. 3227-3236. ISSN 2155-5435. E-ISSN 2155-5435
R&D Projects: GA ČR(CZ) GAP106/12/0189
Institutional support: RVO:61388955
Keywords : olefin metathesis * heterogeneous catalysts * mesoporous molecular sieves
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 9.312, year: 2014

Ruthenium olefin metathesis catalysts bearing a polar quaternary ammonium group in N-heterocyclic ligand were immobilized on silica and siliceous mesoporous molecular sieves with different pore sizes (SBA-15 and MCM-41). The activity of the heterogeneous catalysts was found to increase with an increase in pore size of the support used, with the best results observed for SBA-15-supported catalyst. The influence of reaction conditions (temperature, solvent, catalyst, and substrate concentration) on the efficiency of new heterogeneous catalysts was established. A significant influence of the counterion present in the ruthenium complex on the activity of immobilized catalysts was also found: those derived from chloride containing ion exhibited the highest activity. High activity in ring-closing metathesis of substrates as citronellene, 1,7-octadiene, and diallyl compounds as well as in cross-metathesis of unsaturated aliphatic compounds with methyl acrylate was observed under optimized conditions. In some cases, heterogenization led to catalysts with efficiency higher than those observed for corresponding homogeneous complexes.
Permanent Link: http://hdl.handle.net/11104/0235717