Patent classifications
B01J2231/645
Reduction method and reduction product of alkenyl active methylene compound
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.
3,3,3',3'-tetramethyl-1,1'-spirobiindane-based monophosphine ligand, intermediates thereof, preparation method and use of the same
Provided are a 3,3,3′,3′-tetramethyl-1,1′-spirobiindane-based monophosphine ligand and intermediates thereof, and preparation methods and uses of the same. The monophosphine ligand is a compound represented by formula I or formula I′, or an enantiomer, a raceme or a diastereoisomer thereof, including phosphonite ligands, phosphite ligands, phosphoramidite ester ligands, phosphoric acid and phosphonic amide. The monophosphine ligand is prepared with a known 3,3,3′,3′-tetramethyl-1,1′-spirobiindane-7,7′-diol derivative as a raw material through a scheme in which the compound presented by formula II acts as an intermediate. The present disclosure provides a novel monophosphine ligand, which can be used as a ligand in a metal-catalysed organic reactions or in directly catalyzing an organic reaction, especially as a chiral monophosphine ligand widely used in many chiral catalytic reactions such as asymmetric addition, asymmetric hydrogenation, asymmetric coupling, and asymmetric allyl alkylation, having economic practicality and industrial application prospects. ##STR00001##
Biologically applicable water-soluble heterogeneous catalysts for para-hydrogen induced polarization
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.
CATALYST FOR HYDROGENATION REACTION AND METHOD FOR PRODUCING SAME
A catalyst for a hydrogenation reaction including: a polymer support; and a catalytic component supported on the polymer support. The polymer support includes a repeating unit represented by Formula 1.
Synthesis and use of oxa-spirodiphosphine ligand
The present invention relates to the technical field of chiral synthesis, and specifically provides a new type of oxa-spirodiphosphine ligands. The bisphosphine ligand is prepared with oxa-spirobisphenol as a starting material after triflation, palladium catalyzed coupling with diaryl phosphine oxide, reduction of trichlorosilane, further palladium catalyzed coupling with diaryl phosphine oxide, and further reduction of trichlorosilane. The oxa-spiro compound has central chirality, and thus includes L-oxa-spirodiphosphine ligand and R-oxa-spirodiphosphine ligand. The racemic spirodiphosphine ligand is capable of being synthesized from racemic oxa-spirobisphenol as a raw material. The present invention can be used as a chiral ligand in the asymmetric hydrogenation of unsaturated carboxylic acids. The complex of the ligand with ruthenium can achieve an enantioselectivity of greater than 99% in the asymmetric hydrogenation of methyl-cinnamic acid.
Zwitterion-ruthenium complex for catalytic aerobic oxidation reactions
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.
NICKEL/TITANIUM OXIDE-SILICON OXIDE CATALYST FOR SYNTHESIZING TERPINENE-4-OL, PREPARATION METHOD THEREOF, AND METHOD OF SYNTHESIZING TERPINENE-4-OL USING THE SAME
The present invention discloses a nickel/titanium oxide-silicon oxide catalyst for synthesizing terpinene-4-ol as well as a preparation method and method of synthesizing terpinene-4-ol using the same. The preparation method includes the steps of catalyst preparation, terpinene-4-ol synthesis and the like are disclosed in the present invention. The preparation method includes the following steps: firstly, preparing a mixed colloid of TiO.sub.2 and SiO.sub.2 by using a sol-gel method, and then centrifuging, washing, drying and roasting is performed to prepare a TiO.sub.2—SiO.sub.2 binary oxide; then, preparing Ni/TiO2-SiO2 by dipping in a nickel nitrate solution, and preparing a supported catalyst by drying and roasting; and finally, adopting a terpinolene-4, 8-epoxide a raw material, carrying out isomerization under the dual catalytic action of TiO2-SiO2 and Ni of the supported catalyst, and carrying out hydrogenation to prepare terpinene-4-ol. The preparation method can combine isomerization and hydrogenation reaction on the same catalyst, has good selectivity on terpinene-4-ol, and is simple to operate and high in product yield.
USE OF CATALYSTS FOR THE METATHESIS OF NITRILE RUBBER
The present invention relates to the use of specific catalysts for the metathesis degradation of nitrile rubber (NBR).
The invention further relates to a method for preparing nitrile rubber with reduced molecular weight using specific catalysts.
Electron donor, and method for synthesizing 4, 4′-bipyridine using electron donor
Provided are an electron donor that is easy to handle and can be used to carry out a coupling reaction economically and efficiently through simple operations under mild conditions in a short period of time, and a method for synthesizing 4,4′-bipyridine using the electron donor. The electron donor includes a mixture of a dispersion product obtained by dispersing sodium in a dispersion solvent and 1,3-dimethyl-2-imidazolidinone, and this electron donor is used in the method for synthesizing 4,4′-bipyridine.
Multidentate ligands and use thereof
The present invention provides, inter alia, a multidentate ligand having the structure of: ##STR00001## Also provided are methods of preparing metal complexes from the multidentate ligand, and the metal complexes prepared by such methods. Further provided are catalysts comprising such metal complexes, and various uses of such catalysts.