The present invention discloses a selective hydrogenation catalyst and a preparation method and an application thereof, belonging to the technical field of catalysts. The selective hydrogenation catalyst comprises an active component and a carrier for supporting the active component, wherein the active component is a transition metal particle, the carrier is modified by a flexible chain ligand in advance, one end of the flexible chain ligand is uniformly distributed on the surface of the carrier, and the other end of the flexible chain ligand is coordinated on a transition metal. When the catalyst is used for catalytic hydrogenation reaction of dehydrolinalool or 2-methyl-3-butyn-2-ol, the stability is good, the catalyst still has high selectivity after being used for a long time, and the quality of a hydrogenation product can be guaranteed.

Systems for the catalytic activation and/or dehydrogenation of a paraffin feed stream that is enriched in C5 alkanes to produce olefins that are then hydrated in the presence of water to produce C5 alcohols. Optionally, paraffin isomers are separated and the n-paraffins isomerized prior to catalytic activation and/or dehydrogenation.

The present invention discloses a selective hydrogenation catalyst and a preparation method and an application thereof, belonging to the technical field of catalysts. The selective hydrogenation catalyst comprises an active component and a carrier for supporting the active component, wherein the active component is a transition metal particle, the carrier is modified by a flexible chain ligand in advance, one end of the flexible chain ligand is uniformly distributed on the surface of the carrier, and the other end of the flexible chain ligand is coordinated on a transition metal. When the catalyst is used for catalytic hydrogenation reaction of dehydrolinalool or 2-methyl-3-butyn-2-ol, the stability is good, the catalyst still has high selectivity after being used for a long time, and the quality of a hydrogenation product can be guaranteed.

The present invention discloses a cobalt compound of formula (I), a process for the preparation and use thereof. The present invention further relates to a pharmaceutical composition and a method inhibition of Tau Aggregation in a subject in need thereof using compound of formula (I). ##STR00001##

This invention relates to novel hydrogenation catalyst compositions obtainable from reacting metal-based complex hydrogenation catalysts with specific co-catalysts and to a process for selectively hydrogenating nitrile rubbers in the presence of such novel hydrogenation catalyst compositions.

Disclosed are a reduction method and reduction product of an alkenyl active methylene compound. The reduction reaction comprises the following steps: taking an alkenyl active methylene compound as a substrate, a metal hydride as a reducing agent, and a palladium compound as a catalyst, performing a reduction reaction to obtain a reduction product, and then reducing the alkenyl active methylene compound. The reduction system is a simple method for reducing the alkenyl active methylene compound, and the used hydride and palladium compound catalyst are both reagents that could easily be obtained in a laboratory. Compared with conventional hydrogen hydrogenation methods and reduction methods of reducing agents, the method is easier to operate, higher in safety, mild in conditions, and high in reaction yield, a reaction in a one-pot two-step manner can be achieved, and high atom economy and step economy can be obtained.

The present invention relates to the use of Ru and Os carbene complexes with a hydroxamic acid (ester) function for the metathesis degradation of nitrile rubber (NBR). The invention further relates to a method for producing hydrogenated nitrile rubbers, by subjecting a nitrile rubber to a metathesis degradation in the presence of the said catalyst, and the degraded nitrile rubber obtained subsequently undergoes a hydrogenation, preferably in situ.

Zwitterion ligand metal complexes and methods of aerobic oxidation using a zwitterion ligand metal complex are provided. The zwitterion ligand metal complexes can include a transition metal salt and a zwitterion ligand, which can comprise a non-conjugated amide anion-phosphonium cation, an amide anion-ammonium cation, or an iminium cation. The methods of aerobic oxidation can include combining the zwitterion ligand metal complex with an oxidizable compound and molecular oxygen to allow the isolation of an oxidized compound from the oxidizable compound.

Enantiopure terphenyl presenting two ortho-located chiral axes having the following structural formula (I): their process of synthesis and their use as mono or bidentate ligands for asymmetric organometallic reactions, as organocatalysts, as chiral base and as generator, with metal, of isolable chiral metallic complexes for applications in asymmetric catalysis and others.

Metal-organic framework (MOFs) compositions based on postsynthetic metalation of secondary building unit (SBU) terminal or bridging OH or OH.sub.2 groups with metal precursors or other post-synthetic manipulations are described. The MOFs provide a versatile family of recyclable and reusable single-site solid catalysts for catalyzing a variety of asymmetric organic transformations, including the regioselective boryiation and siiylation of benzyiic CH bonds, the hydrogenation of aikenes, imines, carbonyls, nitroarenes, and heterocycles, hydroboration, hydrophosphination, and cyclization reactions. The solid catalysts can also be integrated into a flow reactor or a supercritical fluid reactor.