A process includes periodically or continuously introducing an olefin monomer and periodically or continuously introducing a catalyst system or catalyst system components into a reaction mixture within a reaction system, oligomerizing the olefin monomer within the reaction mixture to form an oligomer product, and periodically or continuously discharging a reaction system effluent comprising the oligomer product from the reaction system. The reaction system includes a total reaction mixture volume and a heat exchanged portion of the reaction system comprising a heat exchanged reaction mixture volume and a total heat exchanged surface area providing indirect contact between the reaction mixture and a heat exchange medium. A ratio of the total heat exchanged surface area to the total reaction mixture volume within the reaction system is in a range from 0.75 in.sup.1 to 5 in.sup.1, and an oligomer product discharge rate from the reaction system is between 1.0 (lb)(hr.sup.1)(gal.sup.1) to 6.0 (lb)(hr.sup.1)(gal.sup.1).

The present invention relates to stereoselective process for the preparation of a compound having formula (2) and (1) wherein X is defined in the specification.

##STR00001##

A catalyst composition comprises an inert hydrocarbon solvent, having dissolved therein a titanate of the formula Ti(OR).sub.4 wherein each R is the same or different, and is a hydrocarbon residue, and an organic aluminum compound, wherein a molar ratio of the organic aluminum compound and any alkene present in the catalyst composition is greater than one.

The invention concerns an alkane metathesis catalyst, its production and use. The catalyst comprises a Group V, VI or VII metal alkyl with the metal in its highest oxidation state, preferably Ta or W, and the alkyl of C1-C4, preferably together with alkylidene and/or alkylidyne ligands, in particular -Me, CH2 and CH, on a metal oxide support, preferably silica partially dehydroxylated at 200 or 700 C. Substrates include cycloalkanes, preferably cyclooctane.

The present invention relates to a process for treating an effluent obtained from an oligomerization step in a vaporization step. In particular, the oligomerization step is a step for dimerization of ethylene to 1-butene with a nickel-based catalytic system.

A liquid phase process for direct utilization of inorganic metal carbonate and related salts under hydrogenative conditions to produce value-added fuels and feedstocks such as methanol, methane, carbon monoxide, and higher hydrocarbons. Advantageously, the reaction can use heterogeneous catalysts. The hydrogenation proceeds with high selectivity and yield for the desired product at relatively low temperatures, along with co-production of metal hydroxide. The metal hydroxide can be used to capture CO.sub.2, forming metal carbonates and bicarbonates that can be reused to produce more methanol and methane, hydrocarbons and carbon monoxide, closing the loop. Such a hydrogenation process can thus also be used in a carbon capture and recycling manner to produce renewable methane, methanol, carbon monoxide, hydrocarbons, and other carbon feedstocks from CO.sub.2 sourced from any natural and anthropogenic emissions as well as from ambient air.

The present invention provides a process for preparing a 2-(3-alkenyl)-1,3-butadiene compound of the following general formula (A), wherein R.sup.1 and R.sup.2 represent, independently of each other, a hydrogen atom or a linear, branched, or cyclic hydrocarbon group having 1 to 20 carbon atoms and optionally having an unsaturated bond(s), the process comprising the step of subjecting a secondary allylsulfone compound of the following general formula (G), wherein R.sup.1 and R.sup.2 represent, independently of each other, a hydrogen atom or a linear, branched, or cyclic hydrocarbon group having 1 to 20 carbon atoms and optionally having an unsaturated bond(s), W represents an arenesulfonyl group, and Z represents a halogen atom, to a reductive removal of an arenesulfonyl group, W, at an allyl position, and then subjecting the secondary allylsulfone compound (G) to an elimination reaction of a hydrogen halide, HZ, in this order or in reverse order, to form the 2-(3-alkenyl)-1,3-butadiene compound (A).

##STR00001##

There is provided a process for alkylating a substrate with a photocatalytic system. The process comprises providing a mixture containing an acid, and a substrate (an organic compound). Then, an organophotoredox catalyst of formula Ia is contact with the mixture. Finally, the organophotoredox catalyst is activated with a light irradiation to alkylate the substrate and form a carbon covalent bond.

##STR00001##