摘要 |
Disclosed are ruthenium and osmium carbene compounds which are stable in the presence of a variety of functional groups and which can be used to catalyze olefin metathesis reactions on strained and unstrained cyclic and acyclic olefins. Specifically, the present invention relates to carbene compounds of the formula wherein: M is Os or Ru; R and R1 are independently selected from hydrogen and substituent groups C2-C20 alkenyl, C2-C20 alkynyl, C1-C20 alkyl, aryl, C1-C20 carboxylate, C2-C20 alkoxy, C2-C20 alkenyloxy, C2-C20 alkynyloxy, aryloxy, C2-C20 alkoxycarbonyl, C1-C20 alkylthio, C1-C20 alkylsulfonyl or C1-C20 alkylsulfinyl; each substituent group optionally substituted with C1-C5 alkyl, a halogen, C1-C5 alkoxy or with a phenyl group optionally substituted with a halogen, C1-C5 alkyl or C1-C5 alkoxy; X and X1 are independently selected from any anionic ligand; and L and L1 are each trialkyl phosphine ligands where at least one of the alkyl groups on the phosphine is a secondary alkyl or a cycloalkyl. A broad array of metathesis reactions are enabled including ring-opening metathesis polymerization of cyclic olefins, ring closing metathesis of acyclic dienes, cross metathesis involving at least one acyclic or unstrained cyclic olefin, depolymerization of unsaturated polymers and synthesis of telechelic polymers.
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