| 摘要 |
An improved olefin metathesis catalyst system is disclosed. The catalyst system comprises a transition metal halide metathesis catalyst and an organo transition metal hydride co-catalyst of the formula Lx - M - H, wherein M is a group IVB compound, zirconium, titatium or hafnium; L is a ligand selected independently from the group of hydrogen, halide and organic ligands such as an optionally substituted C1-20 alkyl or alkenyl, an optionally substituted C3-20 cycloalkyl or cycloalkenyl having 3 to 6 carbon atoms in the ring, an optionally substituted C5-20 cycloalkadienyl having 5 carbon atoms in the cycloalkadienyl ring, or an optionally substituted C6-20 aryl or fused aryl, where at least one L is a cycloalkadienyl; and x is one less than the valence of M. The optional substitutions on the organic ligands include halogens, preferably chloride or fluoride; C1-6 alkyl; C1-6 alkoxy; and C1-6 haloalkyl. The preferred ligand is a C5-20 cycloalkadienyl having 5 carbon atoms in the cycloalkadienyl group, e.g. cyclopentadienyl. The co-catalysts of this invention are combined with molybdenum or tungsten metathesis catalysts to provide an active catalytic system for the polymerization of cycloolefins, such as dicyclopentadiene.
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