TY - JOUR
T1 - Re-based heterogeneous catalysts for olefin metathesis prepared by surface organometallic chemistry
T2 - Reactivity and selectivity
AU - Chabanas, Mathieu
AU - Copéret, Christophe
AU - Basset, Jean-Marie Maurice
PY - 2003/2/17
Y1 - 2003/2/17
N2 - Herein we describe the catalytic activity of 1, a well-defined Re alkylidene complex supported silica, in the reaction of olefin metathesis. This system is highly active for terminal and internal olefins with initial rates up to 0.7 mol per mol Re per s. It also catalyses the self-metathesis of methyl oleate (MO) without the need of co-catalysts. The turnover numbers can reach up to 900 for MO, which is unprecedented for a heterogeneous Re-based catalyst. Moreover the use of silica as a support can bring major advantages, such as the possibility to use branched olefins like isobutene, which are usually incompatible with alumina-based supports; therefore, the formation of isoamylene from the cross-metathesis of propene and isobutene can be performed. All these results are in sharp contrast to what has been found for other silica- or alumina-supported rhenium oxide systems, which are either completely inactive (silica system) or typically need co-catalysts when functionalised olefins are used. Finally the initiation step corresponds to a cross-metathesis reaction to give a 3:1 mixture of 3,3-dimethylbutene and trans-4,4-dimethylpent-2-ene, and make this catalyst the first generation of well-defined Re-based heterogeneous catalysts.
AB - Herein we describe the catalytic activity of 1, a well-defined Re alkylidene complex supported silica, in the reaction of olefin metathesis. This system is highly active for terminal and internal olefins with initial rates up to 0.7 mol per mol Re per s. It also catalyses the self-metathesis of methyl oleate (MO) without the need of co-catalysts. The turnover numbers can reach up to 900 for MO, which is unprecedented for a heterogeneous Re-based catalyst. Moreover the use of silica as a support can bring major advantages, such as the possibility to use branched olefins like isobutene, which are usually incompatible with alumina-based supports; therefore, the formation of isoamylene from the cross-metathesis of propene and isobutene can be performed. All these results are in sharp contrast to what has been found for other silica- or alumina-supported rhenium oxide systems, which are either completely inactive (silica system) or typically need co-catalysts when functionalised olefins are used. Finally the initiation step corresponds to a cross-metathesis reaction to give a 3:1 mixture of 3,3-dimethylbutene and trans-4,4-dimethylpent-2-ene, and make this catalyst the first generation of well-defined Re-based heterogeneous catalysts.
KW - Functionalized olefins
KW - Heterogeneous catalysis
KW - Metathesis
KW - Rhenium
KW - Silica
UR - http://www.scopus.com/inward/record.url?scp=0037450125&partnerID=8YFLogxK
U2 - 10.1002/chem.200390119
DO - 10.1002/chem.200390119
M3 - Article
C2 - 12584713
AN - SCOPUS:0037450125
SN - 0947-6539
VL - 9
SP - 971
EP - 975
JO - Chemistry - A European Journal
JF - Chemistry - A European Journal
IS - 4
ER -