Compound of formula 4 or formula 5 ##STR00001##
wherein
L is a neutral ligand, preferably a nitrogen-containing heterocyclic carbene (NHC) such as carbene containing at least two nitrogen atoms, a cyclic aminoalkyl carbene (CAAC) or a bicyclic aminoalkyl carbene (BICAAC);
R.sup.1, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8, R.sup.9, R.sup.10 and R.sup.11 are, independently, H, unbranched or branched C.sub.1-20 alkyl, C.sub.5-9 cycloalkyl, unbranched or branched C.sub.1-20 alkoxy, optionally bearing one or more halogen atoms, respectively; or aryl, optionally substituted with one or more of unbranched or branched C.sub.1-20 alkyl, C.sub.5-9 cycloalkyl, unbranched or branched C.sub.1-20 alkoxy, aryl, aryloxy, unbranched or branched C.sub.1-20 alkylcarbonyl, arylcarbonyl, unbranched or branched C.sub.1-20 alkoxycarbonyl, aryloxycarbonyl, heteroaryl, carboxyl, cyano, nitro, amido, aminosulfonyl, N-heteroarylsulfonyl, unbranched or branched C.sub.1-20 alkylsulfonyl, arylsulfonyl, unbranched or branched C.sub.1-20 alkylsulfinyl, arylsulfinyl, unbranched or branched C.sub.1-20 alkylthio, arylthio, sulfonamide, halogen or N(R.sup.y)(R.sup.z), wherein R.sup.y and R.sup.z are independently selected from H and C.sub.1-20 alkyl:
R.sup.2 is H, unbranched or branched C.sub.1-20 alkyl.

The present invention relates to a novel ligand for forming a ruthenium complex, a ruthenium complex catalyst, a production method therefor and a use thereof. The ligand for forming a ruthenium complex and the ruthenium complex catalyst, according to the present invention, exhibit high catalytic activity, high selectivity, and stability.

An improved catalyst for cyclic olefin polymerization. The catalyst includes a transition metal carbene having the following structure: M.sup.v(OR’).sub.c*mX(.sub.v-c*m-2)=C(R*).sub.2 wherein M.sup.v is a Group 5 transition metal having a valence (v) of 5 or a Group 6 transition metal having a valence (v) of 5 or 6; each R′ is independently a monovalent organic moiety comprising from 8 to 40 atoms selected from Groups 14-17; c is an integer from 1 to 3; m is ⅓, ½, 1, 3/2, 2, 3, or 4 and c*m ≤ v-2; X is a halogen; and each R* is independently H or a C.sub.1 to C.sub.7 alkyl. The catalyst is particularly useful for ring-opening metathesis polymerization (ROMP).

The present application provides, among other things, compounds and methods for metathesis reactions. In some embodiments, the present disclosure provides methods for preparing alkenyl halide with regioselectivity and/or stereoselectivity. In some embodiments, the present disclosure provides methods for preparing alkenyl halide with regioselectivity and Z-selectivity. In some embodiments, the present disclosure provides methods for preparing alkenyl halide with regioselectivity and E-selectivity. In some embodiments, provided technologies are particularly useful for preparing alkenyl fluorides. In some embodiments, a provided compound useful for metathesis reactions has the structure of formula II-a. In some embodiments, a provided compound useful for metathesis reactions has the structure of formula II-b.

An organic reductant, in particular an organo silicon reductant suitable for activating supported catalysts of the type MO.sub.nE.sub.m, wherein E is S and/or Se, in particular MO.sub.n, wherein M is W, Mo or Re, is described as well as its use in metathesis reactions. The reduced catalysts are able to metathesize olefins at low temperatures and are therefore also suitable for metathesis of functionalized olefins.

The present invention relates to a catalyst system containing a metathesis catalyst containing at least one N-heterocyclic carbene ligand and at least one phenolic compound and to a process for performing the metathesis on nitrile rubbers for reducing their molecular weight using a metathesis catalyst containing at least one N-heterocyclic carbene ligand (NHC ligand) and at least one phenolic compound.

This invention relates generally to olefin metathesis catalyst compounds, to the preparation of such compounds, compositions comprising such compounds, methods of using such compounds, articles of manufacture comprising such compounds, and the use of such compounds in the metathesis of olefins and olefin compounds. The invention has utility in the fields of catalysts, organic synthesis, polymer chemistry, and industrial and fine chemicals industry.

The present invention relates to a method for the polymerization of cycloolefins by ring-opening metathesis. The reaction is carried out in the presence of at least one particular catalyst, selected from the ruthenium alkylidene complexes comprising at least one 1-aryl-3-cycloalkyl-imidazolin-2-ylidene ligand and mixtures thereof. The invention also relates to a kit for implementing this method.

Subject of the invention is a process for producing a biofuel from fatty acid methyl esters (FAMEs) obtained by transesterification of vegetable oils, comprising the steps of (a) ethenolysis of the fatty acid methyl esters in the presence of ethylene and an ethenolysis catalyst, and (b) isomerizing metathesis in the presence of an isomerization catalyst and a metathesis catalyst.

The invention also relates to biofuels obtainable by the inventive process and to uses of ethylene for adjusting and optimizing biofuels.

The invention provides a method for synthesizing musk macrocycles comprising contacting an easily accessible diene starting materials bearing a Z-olefin moiety and performing a ring closing metathesis reaction in the presence of a Group 8 olefin metathesis catalyst.