The present invention relates to a process for the hydrogenation of the carbon-carbon double bonds in nitrile butadiene rubber which is present in latex form, this means as a suspension of nitrile butadiene rubber particles in an aqueous medium, using a hydrogenation catalyst in the presence of an emulsifier.

The present invention provides an oxa-spirodiphosphine ligand having a structure of general Formula (I) below:

##STR00001##

wherein in general Formula (I), R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are the same, and are alkyl, alkoxy, aryl, aryloxy, or hydrogen, in which R.sup.1, R.sup.2, R.sup.3 and R.sup.4 may or may not form a ring, any two of them may form a ring, or a polycyclic ring may be formed between two pairs of them; R.sup.5 and R.sup.6 is alkyl, aryl, or hydrogen; and R.sup.7 and R.sup.8 is alkyl, benzyl, or aryl. The present invention also provides a method for asymmetric hydrogenation of α,β-unsaturated carboxylic acids. A complex of the oxa-spirodiphosphine ligand with ruthenium shows excellent activity and enantioselectivity in the asymmetric hydrogenation of various α,β-unsaturated carboxylic acids, with which a chiral carboxylic acid product can be obtained with an enantioselectivity up to 99%.

Ru-catalysed domino hydroformylation/hydrogenation/esterification using phosphine ligands.

The present disclosure relates to methods for selectively hydrogenating acetylene, to methods for starting up a selective hydrogenation reactor, and to hydrogenation catalysts useful in such methods. In one aspect, the disclosure provides a method for selectively hydrogenating acetylene, the method comprising contacting a catalyst composition with a process gas. The catalyst composition comprises a porous support, palladium, and one or more ionic liquids. The process gas includes ethylene, present in the process gas in an amount of at least 20 mol. %; acetylene, present in the process gas in an amount of at least 1 ppm; and 0 to 190 ppm or at least 600 ppm carbon monoxide. At least 90% of the acetylene present in the process gas is hydrogenated, and the selective hydrogenation is conducted without thermal runaway.

Disclosed are a liquid hydrogenated nitrile-butadiene rubber, a preparation method therefor and the use thereof. In the liquid hydrogenated nitrile-butadiene rubber: the content of acrylonitrile is 15-50%; the hydrogenation saturation is 75-99.5%; the weight-average molecular weight (Mw) is 3,000-60,000; the molecular weight polydispersity index (PDI) is 2.0-8.0; and the glass transition temperature (Tg) is lower than −28° C. The liquid hydrogenated nitrile-butadiene rubber is low in molecular weight and wide in molecular weight polydispersity, simultaneously has an excellent fluidity during processing and excellent mechanical properties after curing and has a unique application value in the field of special rubbers; and the preparation method therefor is simple and feasible in terms of the process.

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.

A heterogeneous catalyst composition for para-hydrogen induced polarization includes ligand-capped nanoparticles dispersed in water. The ligand-capped nanoparticles include metal nanoparticles that are surface functionalized with organic ligands, a molecular weight of the organic ligands is no greater than 300 g/mol, and the organic ligands each includes multiple binding moieties as coordinates sites for binding to a nanoparticle surface.

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.

Described herein are compositions composed of frustrated Lewis pairs impregnated in porous materials such as, for example, metal-organic frameworks, and their uses thereof. These compositions may allow new applications of frustrated Lewis pairs in catalysis by sequestering and protecting the frustrated Lewis pair within the nanospace of the porous material. Also provided are methods of hydrogenating an organic compound having at least one unsaturated functional group comprising using the compositions described herein.

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.