The invention relates to oligomerization of olefins, such as ethylene, to higher olefins, such as a mixture of 1-hexene and 1-octene, using a catalyst system that comprises a) a source of chromium b) one or more activators and c) a phosphacycle-containing ligating compound. Additionally, the invention relates to a phosphacycle-containing ligating compound and a process for making said compound.

A transition metal-based heterogeneous carbonylation reaction catalyst has an excellent catalytic activity and selectivity in the carbonylation reaction and is easily separated from a product, by crosslinking polymerizing a transition metal-based homogeneous catalyst unit through a Friedel-Craft reaction. The catalyst may be used in a method for preparing lactone. The transition metal-based heterogeneous carbonylation reaction catalyst allows to produce lactone or succinic anhydride with an epoxide compound while showing a high selectivity, and can be applied in industrial very usefully due to easy separation from the product and thus reusing thereof.

The present invention provides novel Ruthenium-based transition metal complex catalysts comprising specific ligands, their preparation and their use in hydrogenation processes. Such complex catalysts are inexpensive, thermally robust, and olefin selective.

The invention relates to oligomerization of olefins, such as ethylene, to higher olefins, such as a mixture of 1-hexene and 1-octene, using a catalyst system that comprises a) a source of chromium b) one or more activators and c) a phosphacycle-containing ligating compound. Additionally, the invention relates to a phosphacycle-containing ligating compound and a process for making said compound.

The invention relates to oligomerization of olefins, such as ethylene, to higher olefins, such as a mixture of 1-hexene and 1-octene, using a catalyst system that comprises a) a source of chromium b) one or more activators and c) a phosphacycle-containing ligating compound. Additionally, the invention relates to a phosphacycle-containing ligating compound and a process for making said compound.

A tetraanionic OCO pincer ligand metal-oxo-alkylidene complex is prepared from a trianionic pincer ligand supported metal-alkylidyne. The metal can be tungsten or other group 5-7 transition metal. The tetraanionic pincer ligand metal-oxo-alkylidene complex, a trianionic OCO pincer ligand metal complex, or a trianionic ONO pincer ligand metal complex can be used to polymerize cycloalkenes. The poly(cycloalkene)s are predominantly cis-alkene macrocyclics.

A method of using homogenous rhodium catalysts comprising N-heterocyclic carbene ligands for the hydroformylation of olefins and substituted olefins is provided. In some aspects, the methods provided herein relate to the hydroformylation of allyl alcohol to 4-hydroxybutaldehyde in the presence of a rhodium catalyst which contains one or more N-heterocyclic carbene ligands of the formula: ##STR00001##
wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are defined herein.

The present invention discloses a diphenylamine-linked chiral bis(oxazoline) ligand without C.sub.2-symmetry of formula 3 and its synthesis method and application in an asymmetric catalytic reaction, wherein C.sub.2-symmetry is lost by introducing different groups into the diphenylamine backbone to realize precise control of “electronic effect” of the ligand backbone. An anthranilic acid derivative and an orthochlorobenzoic acid derivative are used as starting materials to prepare a compound of formula 1, and then the compound of formula 1 is reacted with a chiral amino alcohol compound to prepare a β-bishydroxy amide compound of formula 2, and the compound of formula 2 is further subjected to condensation to obtain the diphenylamine-linked chiral bis(oxazoline) ligand without C.sub.2-symmetry of formula 3. The present invention also provides an application of a catalyst formed by coordination of the diphenylamine-linked chiral bis(oxazoline) ligand without C.sub.2-symmetry with copper salt, zinc salt, nickel salt, iron salt or rhodium salt, in an asymmetric catalytic reaction.

##STR00001##

The present invention may provide an asymmetric hydrogenation catalyst capable of resolving enantiomers with excellent enantioselectivity from a carbon-carbon double bond-containing compound. The catalyst according to one embodiment of the present invention includes: an iridium cation; and a ligand bonded to the iridium cation.

Novel compositions and systems for closure of wounds with antimicrobial effectiveness are disclosed. The compositions provide devices of improved flexibility and elasticity and are readily applied to wound sites or over wound closure devices. The present invention is also directed to a novel platinum catalyst for use in such compositions. The catalyst provides for rapid curing on topical surfaces such as skin and bonds to such surfaces in about 2-5 minutes.