Homo- and hetero metal alkylidene complexes of ruthenium with N-heterocyclic carbene ligands, and their use as highly active and selective catalysts for olefin metathesis

Ruthenium complexes with an anionic ligand, a mono- to tri-dentate, metal-containing ligand attached to the ruthenium by non-ionic bonds, an alkylidene ligand and an N-heterocyclic carbene ligand. Complex ruthenium compounds have the formula (I). X = an anionic ligand; Z = a metal-containing mono- to tri-dentate ligand with non-ionic bond(s) to the central ruthenium atom; R , R = H and/or linear, branched and/or cyclic 1-50C alkyl, 2-50C alkenyl or alkynyl, 6-30C aryl or silyl groups (same or different), in which one or more H atoms may be replaced by alkyl, aryl, alkenyl, alkynyl, metallocenyl, halogen, nitro, nitroso, hydroxy, alkoxy, aryloxy, amino, amido, carboxyl, carbonyl, thio and/or sulfonyl groups, or R and R may form a ring; L = an N-heterocyclic carbene ligand of formula (II)-(V); R -R in formulae (II-V) = as for (I) (except silyl), or R and R may also be halogen, nitro or other functional groups as listed above. An Independent claim is also included for a process for the production of acyclic olefins with 2 or more carbon atoms and/or cyclic olefins with 3 or more C atoms (formula VI) by metathesis of similar olefins of formula (VI) in presence of a complex (I) as catalyst; R' -R' = H, hydrocarbyl, silyl or functional groups as above.