15 results about "Catalytic transfer hydrogenation" patented technology

The invention discloses application of a high-activity Zn-based catalyst Zn (at) Nx / NC in catalytic transfer hydrogenation of 5-hydroxymethylfurfural, and belongs to the technical field of catalyst preparation. The preparation method of the catalyst comprises the following steps: dissolving zinc nitrate hexahydrate and an auxiliary agent in a solvent to obtain a solution A, dissolving a template agent in the solvent to obtain a solution B, adding the solution B into the solution A under violent stirring, and continuously stirring to completely react to obtain a solid precipitate; and roasting the solid precipitate to obtain the Zn-based catalyst Zn (at) Nx / NC. The catalyst can be used for carrying out catalytic transfer hydrogenation on HMF to generate 2, 5-bis (hydroxymethyl) furan and 2, 5-dimethylfuran, C-O bonds and C = O bonds can be efficiently catalyzed, transferred and hydrocracked under mild conditions, the conversion rate of reactants is greater than 98%, and the yield of products is high. The catalyst is simple to prepare, the active metal zinc is non-noble metal, the cost is low, and the reaction activity is high.

The present invention discloses a supported metal oxide catalyst with adjustable acidity and its application in catalytic synthesis of γ-valerolactone. The present invention uses TiO2 as a carrier and 10 )4·xH2O is present to load a metal oxide to prepare the supported metal oxide catalyst. The obtained catalyst can prepare γ-valerolactone by catalytic transfer hydrogenation using an organic alcohol as both a hydrogen donor and a reaction solvent, thereby having a high degree of specificity for the ketone group and not producing excessive hydrogenation products. The present invention uses a cheap and readily available supported metal oxide as a catalyst, has a simple reaction system, does not require an external hydrogen source or other solvents, and is conducive to the separation of the target product. At the same time, the reacted catalyst can be directly used in the next reaction after centrifugation and drying.

The present invention relates to the technical field of the preparation of 2-methylfuran, and particularly to a method for preparing 2-methylfuran by catalytic transfer hydrogenation of furfural. The method comprises the following steps: mixing furfural, a catalyst and a hydrogen donor, and reacting at 220-260 °C for 3-4.5 h to obtain 2-methylfuran. The catalyst is a Cu-Co@Silicalite-1 catalyst, the active components are Cu and Co, and the carrier is Silicalite-1; the Cu content in the catalyst is 2.8-5.1 wt%, and the Co content is 1.6-4 wt%. The present invention uses a non-noble metal catalyst to catalyze the transfer hydrogenation of furfural to prepare 2-MF, which has the advantages of simple process, zero hydrogen consumption and low catalyst cost compared with the existing process. In the present invention, the conversion rate of furfural reaches more than 90%, and the total molar yield of 2-MF can reach more than 80%.

This invention discloses a method for the efficient one-pot synthesis of γ-valerol from furfural. The method involves a simple precipitation or hydrothermal process, followed by rotary evaporation and calcination to obtain a zirconium phosphate-supported H-beta(25) molecular sieve catalyst. The catalytic activity can be improved by adjusting the ratio of zirconium and phosphorus precursors, as well as the mass ratio of zirconium phosphate to zeolite molecular sieve. This zirconium phosphate-supported H-beta(25) molecular sieve exhibits highly efficient catalytic transfer hydrogenation, etherification, and alcoholysis activities, enabling the efficient one-pot synthesis of γ-valerol from furfural in isopropanol.

The application of flower-shaped alumina microspheres in the catalytic transfer hydrogenation of furfural to furfuryl alcohol belongs to the fields of nanomaterials and catalysis. The flower-shaped alumina microspheres utilize ionic surfactants as structure-directing agents and sodium aluminate as the aluminum source; amides are added as precipitants, and the resulting precursor is then calcined. The microsphere preparation process is mild and simple. In the catalytic transfer hydrogenation reaction, the flower-shaped alumina microspheres achieve highly selective conversion of furfural to furfuryl alcohol without the need for precious metals as reactive centers. Furthermore, the reaction does not use molecular hydrogen as a hydrogen source, resulting in low equipment requirements and promising application prospects.

The invention provides a method for preparing recyclable polyester through dehydrogenation polymerization of diketone and primary diol, and belongs to the field of preparation of recyclable polyester. The method comprises the following steps: in an inert atmosphere and a solvent environment, carrying out catalytic transfer hydrogenation on a diketone compound under the action of a ruthenium catalyst to generate a secondary diol intermediate in situ, and then carrying out dehydrogenation polymerization on the secondary diol intermediate and a primary diol compound to obtain polyester. According to the invention, commercial diketone is used for replacing a secondary diol monomer in traditional polycondensation, so that the preparation cost is reduced, and the method has a good industrial prospect. The obtained polyester can be completely depolymerized into primary glycol and secondary glycol monomers under the same catalyst and certain hydrogen pressure, and can be polymerized again to prepare polyester with the structure and the property equivalent to those of an original polymer, so that a monomer-polymer-monomer closed cycle is realized. According to the method, preparation, degradation and recovery of the recyclable polyester are realized, the whole circulation process only relates to dehydrogenation and hydrogenation reactions, the process is green and environment-friendly, and a new method is provided for green preparation of the recyclable polyester.

The invention relates to a synthesis method of N-Boc-4-oxo-3-ethyl piperidinecarboxylate, which comprises the following steps: reacting benzylamine and ethyl acrylate in a continuous flow reactor to obtain 3, 3 '-(benzyl azadiyl) diethyl propionate; the preparation method comprises the following steps: mixing diethyl 3, 3 '-(benzyl azadiyl) dipropionate with a mixed solvent, adding alkali liquor under the protection of nitrogen, and carrying out heating reflux reaction to obtain 1-benzyl-4-oxopiperidine-3-ethyl formate hydrochloride; the preparation method comprises the following steps: mixing 1-benzyl-4-oxopiperidine-3-ethyl formate hydrochloride, a porous catalyst, ammonium formate and an ethanol aqueous solution, carrying out a heating reaction in a nitrogen atmosphere, monitoring raw material disappearance in a system through HPLC, cooling a reaction liquid, adding alkali and Boc anhydride, and carrying out a reaction to obtain N-BOC-4-oxo-3-piperidinecarboxylate. According to the method, the high-purity N-Boc-4-oxo-3-ethyl piperidinecarboxylate is prepared through continuous reaction, intramolecular cyclization and catalytic transfer hydrogenation processes, and the method is low in cost, small in pollution, mild in reaction, safe and suitable for industrial production.

The invention discloses a method for synthesizing chiral fluorine-containing quaternary carbon unsaturated ketone through ruthenium catalytic transfer hydrogenation kinetic resolution, the fluorine-containing quaternary carbon unsaturated ketone is used as a reaction substrate 1, a chiral dinitrogen ligand of ruthenium is used as a catalyst, the chiral fluorine-containing quaternary carbon unsaturated ketone 1 'is synthesized through asymmetric transfer hydrogenation kinetic resolution, and the selectivity factor can reach 214.4. The method is simple and practical to operate, excellent in enantioselectivity and diastereoselectivity and wide in substrate range, and the reaction is green, atom-economical and environment-friendly.

The application discloses a green catalytic hydrogenation preparation method of low-trans fatty acid edible hydrogenated oil, and comprises the following steps: dispersing an amorphous Ni-Fe-P alloy catalyst in pretreated vegetable oil to obtain a catalyst-oil mixture; introducing the catalyst-oil mixture and a hydrogen donor solution into a microchannel reactor with multiple temperature zones to perform gradient hydrogenation reaction; wherein the microchannel reactor is integrated with an electrochemical hydrogen generation unit, and a direct current electric field is applied to at least one temperature zone; after the reaction is completed, the catalyst is separated and recovered, and the hydrogenated oil is post-treated to obtain the low-trans fatty acid edible hydrogenated oil; for the first time, the electrochemical hydrogenation and catalytic transfer hydrogenation two green hydrogenation technologies are integrated in the microchannel reactor, and the reaction path is regulated by combining the electric field, so that the formation of carbonium ion intermediates and double bond isomerization is fundamentally inhibited, the content of trans fatty acids in the final hydrogenated oil is reduced, and the health value of the product is significantly improved.

The invention discloses a preparation method of an Al2O3 microsphere loaded nickel metal bifunctional catalyst with a high specific surface area and application of the Al2O3 microsphere loaded nickel metal bifunctional catalyst in hydrodeoxygenation reaction of biomass derivatives. According to the preparation method, sodium tartrate is taken as a template agent, urea is taken as a precipitator, Al2 (SO4) 3.18 H2O is taken as an aluminum source, Al2O3 microspheres are prepared by adopting a hydrothermal method, then active metal is loaded on an Al2O3 microsphere carrier by adopting an impregnation method, and the Ni / Al2O3 catalyst is synthesized through calcination reduction. The catalyst can efficiently catalyze catalytic transfer hydrogenation (CTH) of biomass derivative compounds such as levulinic acid (LA) to prepare an important chemical intermediate gamma-valerolactone. According to the invention, on the basis that Al2O3 is an acidic site, the active metal component is introduced, so that the catalyst shows good hydrodeoxygenation activity and selectivity of a target product in the reaction process, and efficient hydrodeoxygenation of levulinic acid is realized. The prepared Ni / Al2O3 catalyst has the characteristics of simple preparation process, low cost, mild reaction conditions, high catalytic activity and the like. Even in the absence of exogenous H2, the catalyst can effectively catalyze the cascade reaction of esterification and hydrogenation lactonization, improves the safety of the reaction operation process, and has a good application prospect.

The application provides a non-noble metal catalyst and a preparation method and a method for preparing aromatic amines by catalytic transfer hydrogenation reduction of aromatic nitro compounds, and relates to the technical fields of catalysis and organic synthesis. The non-noble metal catalyst provided by the application comprises carbon cloth and iron trioxide loaded on the carbon cloth. The application provides application of the non-noble metal catalyst in preparation of aromatic amines by catalytic transfer hydrogenation reduction of aromatic nitro compounds. The catalyst is used in preparation of aromatic amines by catalytic transfer hydrogenation reduction of aromatic nitro compounds, and high-pressure environment is not needed, the condition is mild, reduction of different aromatic nitro compound substrates can be realized, and the catalyst has the characteristics of high catalytic activity, high selectivity and recyclability. The results of examples show that when the catalyst is used in preparation of aromatic amines by catalytic transfer hydrogenation reduction of aromatic nitro compounds, the conversion rate of the aromatic nitro compounds is 85-95%, and the selectivity of the corresponding product aromatic amines is 90-98%.

The invention discloses a method and a process for synthesizing and producing deuterated methylamine and salts thereof, and relates to the technical field of synthesis of deuterated methylamine and salts thereof. The method comprises the following steps: reacting methylamine containing C-H bonds or a methanol precursor with a deuterated reagent in the presence of a solid acid-alkali bifunctional catalyst, carrying out multistage catalytic hydrogen-deuterium exchange reaction in a continuous flow fixed bed reactor, and controlling the reaction process through a deuteration reaction kinetics-based model to obtain a deuteration intermediate; deriving the deuterated intermediate into deuterated formaldehyde through oxidation, carrying out catalytic transfer hydrogenation reductive amination reaction on the deuterated formaldehyde and deuterated ammonia in a continuous flow microreactor environment by taking deuterated formic acid as a reducing agent, and dynamically regulating and controlling the raw material proportion through an online monitoring and feedback control system; a reaction product is separated and purified by adopting precise rectification, isotope affinity chromatography and directional crystallization based on pKa regulation in sequence, wherein a separation decision is based on real-time evaluation of light hydrogen impurity concentration and total deuterium concentration in a system.

The invention belongs to the technical field of asymmetric catalysis, and particularly discloses a fosfomycin key intermediate alpha-chloro-beta-hydroxy phosphate compound as well as a synthesis method and application of the fosfomycin key intermediate alpha-chloro-beta-hydroxy phosphate compound. The alpha-chloro-beta-hydroxyl phosphate is shown as a formula II in the specification. The synthesis method comprises the following step: in the presence of a catalyst, reacting a compound as shown in a structural formula I with the catalyst, an organic solvent and a hydrogen source to obtain a compound as shown in a formula II. According to the invention, alpha-chloro-beta-carbonyl phosphate is reduced by an asymmetric catalytic transfer hydrogenation method, and the hydrogenated product can be used as a key intermediate for synthesis of fosfomycin or a fosfomycin derivative. The product obtained by the synthesis method has excellent yield and enantioselectivity. # imgabs0 #

This disclosure provides an application of a nickel-based polyimide catalyst in catalytic transfer hydrogenation. The application includes: adding a biomass derivative substrate, an alcohol hydrogen donor, and a water mixture as solvents to a reaction vessel; and, under an inert atmosphere without external hydrogen, converting the biomass derivative substrate into corresponding cyclopentanone and / or cyclopentanol products through a catalytic transfer hydrogenation reaction. The nickel-based polyimide catalyst comprises a polyimide microsphere support and a nickel metal active component supported on the polyimide microsphere support. This disclosure constructs a composite catalytic system with polyimide microspheres as the support and nickel metal as the active component, utilizing the unique proton enrichment function of the polyimide support to achieve efficient and highly selective hydrogenation conversion of furan aldehyde substrates using an alcohol hydrogen donor as the hydrogen source under a non-hydrogen inert atmosphere.

The application discloses a method for synthesizing methylcyclohexyl diurethane by catalytic transfer hydrogenation of a nitride-based catalyst. The method comprises the following steps: adding a nitride-based catalyst, a hydrogen source and toluene diurethane into a reaction kettle, and reacting at normal pressure and at 40-120 DEG C for 1-10 hours to obtain methylcyclohexyl diurethane; the nitride-based catalyst is a noble metal-supporting / transition metal nitride, and the composition comprises an active metal, a support and a transition metal nitride. The application has the advantages of mild reaction conditions, low equipment cost, environmental friendliness, high process safety and the like. Meanwhile, the designed and prepared noble metal-supporting / transition metal nitride catalyst has the characteristics of high activity, high stability and high selectivity.