| 摘要 |
Penta-coordinated ruthenium catalysts for the metathesis reactions of olefins, in particular ring opening metathesis polymerization (ROMP) of cyclo-olefin monomers, which are cationic complexes represented by formula I, II or III: <CHEM> wherein each of X<1> and X<2>, which may be the same or different, is an optionally substituted C3-C20 hydrocarbon group having an allyl moiety as an end group bonded to the ruthenium atom, or X<1> and X<2> together form a group, optionally substituted, which results from dimerization of an alkene and has at each end an allyl group bonded to the ruthenium atom; L<1> and L<2> are mono-dentate neutral electron donor ligands, preferably highly sterically encumbered neutral electron donor ligands such as alkyl phosphines or amines; L &circ& L is a bidentate neutral electron donor ligand, preferably phosphine, amino, imino, arsine or arphos; L<3> is a solvent molecule or a neutral mono-dentate electron donor ligand; L &circ& L &circ& L is a tridentate electron donor ligand, preferably phosphorus or nitrogen containing ligand; and (AÜ is a counter anion weakly coordinated to the ruthenium atom. |
