TY - JOUR
T1 - Evidence for metal-surface interactions and their role in stabilizing Well-defined immobilized Ru-NHC alkene metathesis catalysts
AU - Samantaray, Manoja K.
AU - Alauzun, Johan
AU - Gajan, David
AU - Kavitake, Santosh
AU - Mehdi, Ahmad
AU - Veyre, Laurent
AU - Lelli, Moreno
AU - Lesage, Anne
AU - Emsley, Lyndon
AU - Copéret, Christophe
AU - Thieuleux, Chloé
PY - 2013/2/27
Y1 - 2013/2/27
N2 - Secondary interactions are demonstrated to direct the stability of well-defined Ru-NHC-based heterogeneous alkene metathesis catalysts. By providing key stabilization of the active sites, higher catalytic performance is achieved. Specifically, they can be described as interactions between the metal center (active site) and the surface functionality of the support, and they have been detected by surface-enhanced 1H-29Si NMR spectroscopy of the ligand and 31P solid-state NMR of the catalyst precursor. They are present only when the metal center is attached to the surface via a flexible linker (a propyl group), which allows the active site to either react with the substrate or relax, reversibly, to the surface, thus providing stability. In contrast, the use of a rigid linker (here mesitylphenyl) leads to a well-defined active site far away from the surface, stabilized only by a phosphine ligand which under reaction conditions leaves probably irreversibly, leading to faster decomposition and deactivation of the catalysts.
AB - Secondary interactions are demonstrated to direct the stability of well-defined Ru-NHC-based heterogeneous alkene metathesis catalysts. By providing key stabilization of the active sites, higher catalytic performance is achieved. Specifically, they can be described as interactions between the metal center (active site) and the surface functionality of the support, and they have been detected by surface-enhanced 1H-29Si NMR spectroscopy of the ligand and 31P solid-state NMR of the catalyst precursor. They are present only when the metal center is attached to the surface via a flexible linker (a propyl group), which allows the active site to either react with the substrate or relax, reversibly, to the surface, thus providing stability. In contrast, the use of a rigid linker (here mesitylphenyl) leads to a well-defined active site far away from the surface, stabilized only by a phosphine ligand which under reaction conditions leaves probably irreversibly, leading to faster decomposition and deactivation of the catalysts.
UR - http://www.scopus.com/inward/record.url?scp=84874600110&partnerID=8YFLogxK
U2 - 10.1021/ja311722k
DO - 10.1021/ja311722k
M3 - Article
C2 - 23362800
AN - SCOPUS:84874600110
SN - 0002-7863
VL - 135
SP - 3193
EP - 3199
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 8
ER -