Disclosed herein are processes, systems, and reaction systems for the oligomerization of ethylene to form an ethylene oligomer product in a reaction zone using a catalyst system having i) a chromium component comprising a heteroatomic ligand chromium compound complex of the type disclosed herein, and ii) an aluminoxane. A C.sub.3+ olefin can be present in the reaction zone for a period of time, where the C.sub.3+ olefin is not an ethylene oligomer formed in-situ within the reaction zone.

The present invention relates to a ligand compound, a catalyst system for olefin oligomerization, and a method for olefin oligomerization using the same. The present ligand compound is a compound having a certain new structure and enables provision of a catalyst system for olefin oligomerization that can oligomerize ethylene with higher catalytic activity.

A method of reducing a C—O bond to the corresponding C—H bond in a substrate, which could be a benzylic alcohol, allylic alcohol, ester or an ether bond beta to a hydroxyl group or alpha to a carbonyl group using a recyclable metal catalyst system. The recyclable catalyst system is also applicable to reducing a C═O bond to the corresponding C—OH bond and then C—H bond. These methodologies can be linked in one-pot to selective oxidation and depolymerizations of aromatic polyols such as lignin.

The present invention relates to a stabilized rhenium-based heterogeneous catalyst, obtainable by a process comprising contacting a rhenium-based heterogeneous catalyst with a stabilizing agent at a temperature in a range from 0-100° C., the stabilizing agent comprising an aliphatic hydrocarbon compound and use thereof.

A chiral platinum complex having a chemical formula (I): ##STR00001##
A method for synthesizing the chiral platinum complex (I), includes: dissolving 0.700 g of Pt(DMSO).sub.2(NO.sub.3).sub.2 in 30 mL of dichloromethane as a solvent to yield a solution; adding 0.450 g of 1,4-(4R)-diphenyl-2-oxazolinyl benzene to the solution, and reflux a resulting mixture for reaction for 48 hrs, and stopping the reaction; filtrating reaction products; and adding dichloromethane and petroleum ether, and naturally volatilizing to yield a binuclear platinum complex single crystal. A method for condensation of benzophenone imine and trimethylsilitrile by using the chiral platinum complex as a catalyst. A method for treating cancer includes administering the chiral platinum complex to a patient in need thereof. The cancer includes: lung cancer (A549), nasopharyngeal carcinoma (KB), anti-drug-resistant nasopharyngeal carcinoma (KB-VIn), and human breast cancer (MCF-7).

This disclosure relates to processes for converting saturated polyethylene to at least an alkene product. The processes comprise contacting the saturated polyethylene with three or more catalyst components in a reactor, the reactor comprising an alkene reactant. The three or more catalyst components comprise a metathesis catalyst component, an isomerization catalyst component, and a dehydrogenation catalyst component. Contacting causes at least a portion of the saturated polyethylene to undergo dehydrogenation reactions to form unsaturated polyethylene and at least a portion of the unsaturated polyethylene, or products derived therefrom, to undergo metathesis reactions and isomerization reactions to produce an effluent comprising at least the alkene product.

A catalyst system that may reduce polymeric fouling may include at least one titanate compound, at least one aluminum compound, and an antifouling agent. The antifouling agent may be chosen from one or more of a phosphonium or phosphonium salt; a sulfonate or a sulfonate salt; a sulfonium or sulfonium salt; an ester including a cyclic moiety; an anhydride; a polyether; and a long-chained amine-capped compound. The catalyst system may further include a non-polymeric ether compound.

Provided is an application of a metal hydride/palladium compound system in the preparation of a 1,3-dicarbonyl compound in a cascade reaction of an electron-deficient alkene compound, said reaction comprising the following steps: under the protection of nitrogen, a palladium compound and a metal hydride are suspended and stirred in a solvent, then an electron-deficient alkene compound is added; the mixture reacts at 0° C. to 100° C. for 0.3 to 10 hours; a saturated ammonium chloride aqueous solution is added to stop the reaction, and then extraction, drying by evaporation and purification by column chromatography are performed to obtain the product of 1,3-dicarbonyl compound. The hydride and palladium compound catalysts used in the method are reagents easily obtained in a laboratory; compared with the commonly used methods of hydrogenation with hydrogen gas, the method can be easily operated, and has high safety, mild conditions and high reaction yield.

A catalyst system that may reduce polymeric fouling may include at least one titanate compound, at least one aluminum compound, and an antifouling agent. The antifouling agent may be chosen from one or more of a phosphonium or phosphonium salt; a sulfonate or a sulfonate salt; a sulfonium or sulfonium salt; an ester including a cyclic moiety; an anhydride; a polyether; and a long-chained amine-capped compound. The catalyst system may further include a non-polymeric ether compound.

A method of forming dialkyl carbonate is provided, which includes introducing carbon dioxide into a catalyst to form dialkyl carbonate, wherein the catalyst is formed by activating a catalyst precursor using alcohol, wherein alcohol is R.sup.3—OH, and R.sup.3 is C.sub.1-12 alkyl group or C.sub.5-12 aryl or heteroaryl group. The catalyst precursor is formed by reacting Sn(R.sub.1).sub.2(L).sub.2 and Ti(OR.sup.2).sub.4, and Sn(R.sup.1).sub.2(L).sub.2 and Ti(OR.sup.2).sub.4 have a molar ratio of 1:2 to 2:1. R.sup.1 is C.sub.1-10 alkyl group, R.sup.2 is H or C.sub.1-12 alkyl group, and L is O—(C═O)—R.sup.5, and R.sup.5 is C.sub.1-12 alkyl group. The dialkyl carbonate is ##STR00001##