Method of forming a trisubstituted ethylene compound, the method comprising: (A) providing a trisubstituted ethylene compound bearing a first, a second and a third substituent, in which the first and the second substituent are bound to the one olefinic carbon atom and are different from one another; (B) providing a monosubstituted ethylene compound or a disubstituted ethylene compound in which the substituents are vicinally bound to the olefinic carbon atoms, bearing at least a fourth substituent, respectively; (C) subjecting the trisubstituted ethylene compound provided in step (A) to a cross-metathesis reaction with olefin provided in step (B) to form said trisubstituted ethylene, wherein the cross-metathesis reaction is catalysed by a transition metal complex bearing ligands from which one ligand is a carbene ligand, wherein the carbene complex is characterized by a MC moiety, wherein M is the transition metal; and wherein the reaction proceeds stereoselectively.

Disclosed is a zinc-imidazole complex mixed catalyst. Also disclosed are a method for preparing the zinc-imidazole complex mixed catalyst and a method for producing a methyl N-phenyl carbamate in high yield with high selectivity in the presence of the catalyst. The zinc-imidazole complex mixed catalyst can be reused due to its high reaction stability. In addition, the use of the zinc-imidazole complex mixed catalyst leads to a marked improvement in the production yield of a methyl N-phenyl carbamate with high selectivity.

The present invention relates to kinetic resolution of racemic -hydroxyl ester via asymmetric catalytic hydrogenation and an application thereof. In the presence of chiral spiro pyridyl phosphine ligand Iridium catalyst and base, racemic -hydroxyl esters were subjected to asymmetric catalytic hydrogenation to obtain extent optical purity chiral -hydroxyl esters and corresponding 1,5-diols. An optically active chiral -hydroxyl ester and 1,5-diols can be obtained at very high enantioselectivity and yield with relatively low usage of catalyst. The chiral -hydroxyl ester and 1,5-diols obtained by using the method can be used as a critical raw material for asymmetric synthesis of chiral drugs (R)-lisofylline and natural drugs (+)-civet, ()-indolizidine 167B and ()-coniine.

Catalysts and methods for transformation of glycerol and a carbon feedstock, such as CO.sub.2, a carbonate salt or a bicarbonate salt, are described herein. Homogeneous catalysts include compounds of formula M[NHC-R-linker]aLbXc, where M is a transition metal, NHC is an N-heterocyclic carbene ligand, R is an alkyl or aryl group, linker is a polar group, L is a neutral ligand, X is an anionic ligand, a ranges from 1-3, b ranges from 0-3, and c ranges from 0-3. Heterogeneous catalysts include a solid support with a catalytically active compound immobilized on the solid support, where the catalytically active compound has the formula M[NHC-R-linker]aLbXc where M is a transition metal, NHC is an N-heterocyclic carbene ligand, R is an alkyl or aryl group; linker is a polar group, L is a neutral ligand, X is an anionic ligand, a ranges from 1-3, b ranges from 0-3, and c ranges from 0-3.

Conversion of vegetable-derived triglycerides to fatty acid methyl esters (FAMEs) is a popular approach to the generation of biodiesel fuels and the basis of a growing industry. Drawbacks of the strategy are that (a) the glycerol backbone of the triglyceride is discarded as waste in this synthesis, and (2) many natural triglycerides are multiply-unsaturated or fully saturated, giving inferior performance and causing engine problems with long-term use. Here, we show that catalysis by iridium complex 1 can address both of these problems through selective reduction of triglycerides high in polyunsaturated fatty esters to FAMEs with high oleate concentration. This is realized using hydrogen imbedded in the triglyceride backbone, concurrently generating lactate as a value-added C.sub.3 product. Additional methanol or glycerol as a hydrogen source enables reduction of corn and soybean oils to >80% oleate.

The invention concerns a catalytic composition comprising: at least one nickel precursor with an oxidation number of (+II), at least one phosphine ligand with formula PR.sup.1R.sup.2R.sup.3 in which the groups R.sup.1, R.sup.2 and R.sup.3, which may be identical or different and which may or may not be bonded together, and at least one Lewis base, said composition having a molar ratio of the phosphine ligand to the nickel precursor of less than or equal to 5 and a molar ratio of the Lewis base and phosphine ligand together to the nickel precursor of greater than or equal to 5.

A highly efficient, Z-selective ring-closing metathesis system for the formation of macrocycles using a stereoretentive, ruthenium-based catalyst supported by a dithiolate ligand is reported. This catalyst is demonstrated to be remarkably active as observed in initiation experiments showing complete catalyst initiation at 20 C. within 10 min. Using easily accessible diene starting materials bearing a Z-olefin moiety, macrocyclization reactions generated products with significantly higher Z-selectivity in appreciably shorter reaction times, in higher yield, and with much lower catalyst loadings than in previously reported systems. Macrocyclic lactones ranging in size from twelve-membered to seventeen-membered rings are synthesized in moderate to high yields (68-79% yield) with excellent Z-selectivity (95%-99% Z).

Markovnikov-selective palladium catalyst for carbonylation of alkynes is formed from a bisphosphite having formula (1): ##STR00001## The carbonylation catalyst is suited for the preparation of a branched heteroarene-keto product from an alkyne substrate, CO and heterocycle in high yields with low amounts of the linear product.

Disclosed is a zinc-imidazole complex mixed catalyst. Also disclosed are a method for preparing the zinc-imidazole complex mixed catalyst and a method for producing a methyl N-phenyl carbamate in high yield with high selectivity in the presence of the catalyst. The zinc-imidazole complex mixed catalyst can be reused due to its high reaction stability. In addition, the use of the zinc-imidazole complex mixed catalyst leads to a marked improvement in the production yield of a methyl N-phenyl carbamate with high selectivity.

The present invention provides compositions comprising metal complexes, and related methods. In some embodiments, metal complexes of the invention may be useful as catalysts for chemical reactions, including metathesis reactions, wherein the catalysts exhibit enhanced activity and stereoselectivity. In some embodiments, the invention may advantageously provide metal complexes comprising a stereogenic metal atom. Such metal complexes may be useful in enantioselective catalysis.