214 results about "Aldol condensation" patented technology

The invention relates to an ammonia distillation-polymerization carbonization one-step preparation method and application of a carbon-modified copper-silicon catalyst. According to the method, carbon is introduced through aldol condensation on the basis of an ammonia distillation method Cu / SiO2 catalyst, and a carbon modified Cu / Si C-x catalyst is prepared; the proper carbon content can promote dispersion of copper on the surface, increase the proportion of Cu < + > / (Cu < + > + Cu0) and remarkably increase the number of Cu < + > sites on the surface of the catalyst, so that the catalytic performance of the catalyst is improved. According to the method, the purpose of carbon modification is achieved without any template agent or acid-base etching agent, a good methyl laurate hydrogenation effect is achieved, and meanwhile the catalyst preparation process is environmentally friendly.

The invention discloses a preparation method of a multifunctional group synergistic modified aluminum silicate nanofiber membrane, which comprises the following steps: modifying aluminum silicate nanofiber by using an amino silane coupling agent to obtain aminated aluminum silicate nanofiber; grafting a polyamino compound to the surface of the aminated aluminum silicate nanofiber by utilizing the cross-linking effect of 1, 3-dichloropropanol through a substitution reaction of amino and chlorine, so as to obtain a multifunctional aluminum silicate nanofiber; 2-butenal is modified on the surface of the multi-functionalized aluminum silicate nanofiber by utilizing an ammonia-aldehyde condensation reaction, so that the multi-functionalized aluminum silicate nanofiber rich in double bonds is obtained; carrying out cross-linking polymerization by taking itaconic acid as a monomer and the multi-functional aluminum silicate nanofiber rich in double bonds as a cross-linking agent, then carrying out suction filtration to form a membrane, and drying to obtain the multi-functional synergistic modified aluminum silicate nanofiber membrane with the gram weight not exceeding 15g / m < 2 >. According to the invention, high-efficiency adsorption of heavy metals is realized, and the problem that aluminum silicate nanofibers are not easy to recover is solved.

The invention discloses a degradable armed acetal epoxy monomer and a preparation method thereof, the acetal epoxy monomer has the following molecular structure general formula: # imgabs0 #, in the formula, R1, R2, R3 and R4 are independently selected from one of hydrogen, methoxyl and ethyoxyl. The degradable acetal epoxy monomer is prepared through the aldol condensation reaction, the thermosetting epoxy resin prepared from the epoxy monomer and the curing agent can be rapidly degraded under the normal-pressure, mild and specific conditions, and huge economic and environmental advantages are achieved for recycling and reusing of the thermosetting resin. When the prepared degradable epoxy resin is used in thermosetting epoxy resin, under the degradation condition provided by the invention, a thermosetting epoxy resin matrix is degraded into alcohol and aldehyde with relatively small molecular weight, the mixture can be dissolved in an organic solvent, and a degradation product can be extracted through simple separation, so that the purpose of recovering the resin is achieved.

The invention relates to a preparation method of a high-lithium-affinity vinylene covalent organic framework material serving as a lithium metal negative electrode interface protective layer. The method comprises the following steps: firstly, by utilizing a simple hydrothermal synthesis method, taking 1, 3, 5-trimethyl-2, 4, 6-triazine (TMT) and 2, 2-bipyridine-5, 5-diformaldehyde (BPY) as monomers, and carrying out Aldol condensation reaction to synthesize a covalent organic framework material connected by a vinylene bond, which is named as viCOF-bpy; the electrochemical performance of the material is verified by modifying the surface of a copper pole piece with the viCOF-bpy material and then assembling a battery. The lithium-loving group on the material skeleton can promote the migration of lithium ions, and the vinylidene has very strong chemical stability, so that the electrochemical performance of the lithium metal battery can be effectively improved.

The invention discloses a long-acting environment-friendly flame-retardant anti-static rubber pad and a preparation method thereof, and relates to the technical field of rubber pads. The long-acting environment-friendly flame-retardant anti-static rubber pad prepared by the application comprises the static conductive layer at the bottom layer and the static dissipation layer attached to one surface of the static conductive layer. The static dissipation layer comprises modified nitrile rubber, acrylate resin and a first auxiliary agent; and the static conductive layer comprises modified nitrile rubber, butadiene styrene rubber, polyurethane resin and a second auxiliary agent. Wherein the modified nitrile rubber is obtained by reacting a Grignard reagent RMgBr with cyano groups in nitrile rubber, converting the cyano groups into carbonyl groups, and introducing a phosphorus-containing organic compound into the nitrile rubber by utilizing aldol condensation. The rubber pad prepared from the modified nitrile rubber is excellent in anti-static performance, has flame retardance, is long-acting and environment-friendly, and has a wide application prospect.

The present invention discloses a catalyst for aldol condensation reaction, its preparation and application, specifically relating to a method for preparing a catalyst for aldol condensation reaction using biomass-based SiO2 and using the catalyst to catalyze the preparation of methyl methacrylate from a mixed solution (or mixed aqueous solution) of formaldehyde and methyl propionate; the loading amount of the active metal on the catalyst is 1-10 wt%, and the total loading amount of the promoter is 0.5-5 wt%. The catalyst provided by the present invention has excellent water resistance and stability. The catalytic reaction is carried out in a fixed-bed reactor, and the carrier gas is an oxygen-containing inert atmosphere. The raw material formaldehyde in the reaction system can be obtained from methanol, and both methanol and the carrier SiO2 can be derived from biomass. Thus, under the background of aiming at "dual carbon" and popularizing green consumption, the high-value utilization of biomass resources is realized, and further the innovation of green and low-carbon technologies is achieved.

The invention discloses an L-threonine aldolase mutant and application of the L-threonine aldolase mutant in synthesis of L-serine. The mutant is obtained by performing single mutation on the 88th amino acid of a wild type L-threonine aldolase amino acid sequence shown as SEQ ID No.2. The invention further discloses a preparation method of the L-threonine aldolase mutant. The invention provides the L-threonine aldolase mutant with better catalytic performance, aldol condensation reaction of formaldehyde and glycine can be efficiently catalyzed to prepare L-serine under the condition of not adding a tetrahydrofolic acid precursor, the yield of the L-serine is increased to 72.3% from 56.7% before mutation, the yield is remarkably increased, and the L-threonine aldolase mutant has the advantages that the L-threonine aldolase mutant has a good application prospect. Good application prospects are shown in the synthesis of the L-serine.

The invention belongs to the field of organic synthesis, and discloses an aldol condensation reaction method and a catalyst thereof.The method comprises the steps that in the presence of a composite catalyst, a substrate 1 and a substrate 2 are subjected to an aldol condensation reaction, after the reaction is finished, an aldol condensation product is collected from reaction products, according to the method, aldol condensation reaction of fatty aldehyde or aromatic aldehyde is catalyzed by adopting the novel composite catalyst, and the method has the advantages of being mild in reaction condition, environmentally friendly, efficient and simple in post-treatment.

The invention provides a preparation method of an omariglitazone intermediate, which comprises the following steps: by taking p-halogenated benzaldehyde as a raw material, carrying out aldol condensation reaction, hydrolysis, decarboxylation, reduction, ring closing and the like to obtain an intermediate as shown in a formula 9, carrying out catalytic reaction, reduction reaction, ring closing and the like to obtain an intermediate as shown in a formula 13, and finally hydrolyzing to obtain a target product omariglitazone intermediate A. According to the invention, links of precious metal use and chiral resolution (key steps influencing cost and yield) in the prior art are avoided, and a method for synthesizing a single configuration through a chemical method is adopted, so that the yield is greatly improved, and the production cost is greatly reduced; meanwhile, a synthesis route is broken through, a target product is synthesized through cheap initial materials, and post-treatment is simpler and more controllable.

The invention discloses a preparation method and application of an aldol condensation catalyst with a Si-O-Zr framework constructed through in-situ doping. The preparation method mainly comprises preparation and application of the Si-O-Zr framework constructed through in-situ doping and the aldol condensation catalyst. Wherein the in-situ doping construction of the Si-O-Zr framework mainly utilizes the pre-hydrolysis matching of a silicon source and the hydrolysis / polycondensation rate between a zirconium source to realize the atomic-scale dispersion of the active component, a proper pore structure can be provided for the subsequent loading of the active component, the possibility of clustering of the active component is reduced, the catalytic activity is further improved, and the method is simple in preparation and low in cost. The method is suitable for subsequent large-scale industrial application.

The present invention belongs to the technical field of covalent organic frameworks, and particularly relates to a method for preparing a single-crystalline vinylidene-bridged covalent organic framework. The method for preparing a single-crystalline vinylidene-bridged covalent organic framework comprises: mixing a single-crystalline imine-linked covalent organic framework, an active monomer, a catalyst and an organic solvent until uniform, and then performing a substitution reaction, wherein the substitution reaction is one or more of an aldol condensation reaction, a Knoevenagel condensation reaction, and a Claisen-Schmidt reaction. The single-crystalline vinylidene-bridged covalent organic framework having good stability, rich active sites, high photoelectric activity and a high conjugation degree is obtained by means of a substitution reaction of the single-crystalline imine-linked covalent organic framework and the active monomer under the action of a catalyst.

The invention relates to the technical field of alcohol preparation through aldehyde hydrogenation, in particular to a butyraldehyde, valeraldehyde and 2-propyl heptanal liquid-phase hydrogenation method and device, the device comprises a liquid-phase hydrogenation reactor, butyraldehyde, valeraldehyde and PBA, the liquid-phase hydrogenation reactor comprises an inner core pipe filled with a hydrogenation catalyst and an outer annular bed, and the outer annular bed is filled with a hydrogenation catalyst. The method is characterized in that butyraldehyde, valeraldehyde and PBA generated by an aldehyde-aldehyde condensation reaction are respectively fed into a hydrogenation system, the reactions of generating 2-propyl heptanol through PBA hydrogenation, generating butanol through butyraldehyde hydrogenation and generating pentanol through valeraldehyde hydrogenation are carried out in a liquid phase, and the pressure is about 2.4 MPa. Compared with gas-phase hydrogenation in the prior art, the liquid-phase hydrogenation adopted in the method has the advantages that the energy consumption is lower; the problem of high energy consumption of gas phase hydrogenation is solved.

The present invention discloses a photocatalyst for the regeneration of coenzyme NADH and a preparation method thereof, wherein the photocatalyst is a donor-π-acceptor type conjugated organic polymer, with a triazine-based ligand as an acceptor unit and a heterocyclic ligand as a donor unit, wherein the molar ratio of the triazine-based ligand to the heterocyclic ligand is 1:(1-2), the triazine-based ligand raw material selects 2,4,6-trimethyl-1,3,5-triazine, and the heterocyclic ligand raw material selects a heterocyclic diformaldehyde containing a furan or thiophene structure. The photocatalyst is prepared by a solvothermal method through a Knoevenagel aldol condensation reaction, the reaction solvent selects a mixed solvent of n-butanol and o-dichlorobenzene or a mixed solvent of mesitylene and 1,4-dioxane, and the catalyst used in the reaction selects at least one of trifluoroacetic acid, potassium hydroxide, 1,8-diazabicycloundecane-7-ene, sodium hydroxide, and cesium carbonate. The developed photocatalyst has a donor-π-acceptor type conjugated structure, and has high catalytic activity, high selectivity, good stability, and easy separation and recovery for the regeneration of coenzyme NADH.

The present application relates to the technical field of alcohol aldehyde condensation reaction, and discloses an alcohol aldehyde condensation reaction method.The alcohol aldehyde condensation reaction method is carried out in an alcohol aldehyde condensation reaction device, the alcohol aldehyde condensation reaction device comprises a micro-channel alcohol aldehyde condensation reactor and an alcohol aldehyde condensation tube reactor which are connected in series; in the presence of an alkali catalyst, a reaction raw material n-butyl aldehyde is subjected to a first alcohol aldehyde condensation reaction in the micro-channel alcohol aldehyde condensation reactor to obtain a first alcohol aldehyde condensation reaction product; and the first alcohol aldehyde condensation reaction product is subjected to a second alcohol aldehyde condensation reaction in the alcohol aldehyde condensation tube reactor.The method uses a micro-channel alcohol aldehyde condensation reactor and an alcohol aldehyde condensation tube reactor to replace a full-mixing kettle reactor in the prior art to carry out alcohol aldehyde condensation reaction, so that the yield of a by-product heavy carbon alcohol can be significantly reduced, and the yield of a target product can be improved.

The invention relates to the technical field of pharmaceutical chemicals, relates to metal-loaded mesoporous silica and application thereof in synthesis of cyclic acid, and particularly relates to preparation of mesoporous silica simultaneously loaded with Mg, Al and Ca and application of the mesoporous silica as a catalyst in aldol condensation reaction for preparation of cyclic acid. The metal-loaded mesoporous silica is prepared by adopting an excessive impregnation method. The metal is one or more of Mg, Al, Ca, Co and Cu. The metals are derived from their nitrates, hydrochlorides or sulfates. When the metal is a combination of Mg, Al and Ca, the corresponding concentrations of magnesium nitrate, aluminum nitrate and calcium nitrate are 3.5-6.5 g / L, 6.5-7.5 g / L and 2.4-4.0 g / L respectively. The metal-loaded silicon dioxide provided by the invention can be used as a catalyst, and especially can be used as a catalyst for aldol condensation reaction to catalyze and synthesize cyclic acid, so that the reaction cost is reduced, and the yield and purity of the product can be obviously improved.

The invention relates to the technical field of chemical synthesis, in particular to a dihydropyrazole derivative, a preparation method thereof and application of the dihydropyrazole derivative in preparation of antibacterial drugs. The dihydropyrazole derivative is prepared from corresponding raw materials through aldol condensation, Michael addition and acylation reaction, the reaction conditions are mild, the steps are simple, and the raw materials are low in cost and easy to obtain. The compound has excellent activity of resisting staphylococcus aureus, methicillin-resistant staphylococcus aureus, ampicillin-resistant staphylococcus aureus, pseudomonas aeruginosa and bacillus subtilis. The invention is of great significance to development and research of new antibacterial drugs.

The present invention relates to the technical field of organic synthesis. Provided is a method for preparing 2,6-bis(4-azidobenzylidene)-4-methylcyclohexanone, comprising the following steps: S1, subjecting 4-nitrobenzaldehyde and trimethylsilyl azide to a nucleophilic aromatic substitution reaction to obtain 4-azidobenzaldehyde; S2, subjecting 4-azidobenzaldehyde and 4-methylcyclohexanone to an aldol condensation reaction, so as to obtain 2,6-bis(4-azidobenzylidene)-4-methylcyclohexanone. The described technical solution addresses the problems in the related art where the process for synthesizing 2,6-bis(4-azidobenzylidene)-4-methylcyclohexanone has low product yield, high costs and high energy consumption, and is not conducive to large-scale industrial production.

The modified titanium silicalite molecular sieve is characterized by containing titanium, silicon, oxygen and cesium elements, the MAS NMR spectrogram of the 133Cs at least has resonance absorption peaks of-94 + / -15 ppm,-73 + / -15 ppm and-36 + / -15 ppm. The modified titanium silicalite molecular sieve can be used in aldol condensation reaction.

The invention relates to preparation and application of a high-elastic UV (ultraviolet) monomer diisooctyl itaconate. The n-butyraldehyde is used as a starting raw material, and the raw material is low in price and wide in source. The appropriate acidic ionic liquid catalyst is screened out, aldol condensation reaction and esterification reaction can be catalyzed at the same time, other solvents are not needed, after the reaction in the step (1) and the step (2) is completed in the reaction process, aftertreatment is not needed, the next-step reaction can be directly conducted, operation steps are saved, and industrialization is better facilitated.

The present invention belongs to the technical field of aviation fuel preparation, and specifically relates to a method for synthesizing thermally stable aviation kerosene from 2,5 - hexanedione. The method comprises the following steps: 1) Using 2,5 - hexanedione as a raw material and an alkali solution as a catalyst, an unsaturated ketone compound with twelve carbon atoms is obtained through an alkali - catalyzed aldol condensation reaction; 2) The unsaturated ketone compound obtained in step 1) undergoes a hydrodeoxygenation reaction under the action of a ternary mixed metal oxide catalyst to obtain a saturated cycloalkane liquid fuel with twelve carbon atoms containing alkyl decalin. The method of the present invention simplifies the current route for preparing alkyl decalin from biomass, and the intermediate products and the final product do not need to undergo a purification / distillation process; significantly reduces the production cost, the raw materials are cheap and easily available, the reaction conditions are mild, and it is suitable for large - scale industrial production.

The invention discloses a preparation method of a composite nanofiltration membrane, which is characterized in that the surface of an ultrafiltration membrane is coated with natural low-cost biological materials carrageenan and sodium carboxymethyl cellulose, so that the environmental friendliness and technical feasibility in the field of water treatment are enhanced; the preparation method comprises the following steps: firstly preparing a composite membrane, then carrying out cross-linking modification on the surface of the membrane through aldol condensation reaction, and constructing a compact and stable three-dimensional network structure selection layer after cross-linking, so that the composite membrane keeps structural stability under extreme pH conditions and in an oxychlorination environment, meanwhile, the composite membrane is endowed with efficient nanofiltration performance, and the composite membrane can be practically applied to industrial chromium-containing wastewater.

The present application relates to the technical field of chemical essence and flavor, and particularly relates to a decenoic acid ester compound, a preparation method and application thereof, and comprises the following steps: (1) preparing 2-(4-methyl-benzylidene) heptanal: under the condition of an inorganic alkaline reagent, p-methylbenzaldehyde and n-heptanal are subjected to aldol condensation reaction to synthesize 2-(4-methyl-benzylidene) heptanal; (2) preparing 2-(4-methyl-benzylidene) heptyl alcohol: under the condition of a reducing agent, 2-(4-methyl-benzylidene) heptanal is reduced to 2-(4-methyl-benzylidene) heptyl alcohol; (3) preparing 5-decenoic acid 2-(4-methyl-benzylidene) heptyl alcohol ester: under the catalysis of an acid, 5-decenoic acid and 2-(4-methyl-benzylidene) heptyl alcohol are subjected to esterification to synthesize 5-decenoic acid 2-(4-methyl-benzylidene) heptyl alcohol ester. The compound in the present application has jasmine aroma and milk aroma, has elegant aroma, has long-lasting aroma, and has important use in the field of daily chemical flavoring.

The invention discloses a preparation method of a polyol acrylate compound, which comprises the following steps: (1) under an esterification reaction condition, contacting a polyol compound with an alkyl acid compound and / or an alkyl ester compound for esterification reaction to obtain an intermediate product; wherein the esterification reaction is carried out in the presence of an acidic material; (2) under aldol condensation reaction conditions, contacting the intermediate product obtained in the step (1) with formaldehyde and a polymerization inhibitor for aldol condensation reaction to obtain a polyol acrylate compound; wherein the aldol condensation reaction is carried out in the presence of an alkaline substance. According to the method disclosed by the invention, side reactions such as polymerization in an acrylic acid esterification process can be avoided, and a high-purity polyol acrylate compound is obtained; meanwhile, the reaction conditions are mild.

The invention provides a difunctional acid-base synergistic catalyst, a preparation method and application in aldol condensation reaction, the catalyst is a modified halloysite nanotube-loaded barium-based catalyst, the modified halloysite nanotube-loaded barium-based catalyst is adopted for acid-base synergistic catalysis, the catalytic activity of the catalyst is greatly improved, and the catalytic activity of the catalyst is improved. The aldol condensation reaction is rapidly carried out, and the reaction yield is up to 98.0%. The method is mild in reaction condition, simple in production process, clean and environment-friendly in process and high in continuity degree, and the catalyst is easy to prepare and high in stability.

A modified titanium silicalite molecular sieve, which is characterized by containing titanium, silicon, oxygen and cesium, wherein the 133Cs MAS NMR spectrum thereof at least has resonance absorption peaks at -94±15 ppm, -73±15 ppm and -36±15 ppm. The modified titanium silicalite molecular sieve can be used in the aldol condensation reaction.

The present invention discloses a method for synthesizing polycyclic alkanes from phenols derived from lignin via a one-pot two-step process. 1) In the first step of the reaction, the phenolic compound derived from lignin is first converted into a ketone compound under the action of a hydrogenation catalyst, and then the ketone compound rapidly undergoes aldol condensation under the action of a solid acid to generate a jet fuel precursor; 2) In the second step of the reaction, the product of the first step is not separated, but the reaction conditions are directly strengthened. The jet fuel precursor is directly subjected to complete hydrodeoxygenation to generate polycyclic alkanes under the action of the hydrogenation catalyst and the solid acid in the first step; the phenolic compound derived from lignin is synthesized into polycyclic jet fuel by changing the reaction conditions in a single reaction vessel. Compared with traditional chain-like jet fuel, it has a higher density and a higher calorific value and can be used as a substitute for traditional aviation fuel. The catalyst and raw materials used in the present invention are abundant in source, low in price, and easy to separate; the entire production process is simple to operate.

The invention discloses a breast cancer inhibitor, a preparation method, a pharmaceutical composition and application. The inhibitor is efficiently synthesized through two-step reaction (Aldol condensation and acid catalysis cyclization dehydration) by taking a compound with a specific structure as a core, the reaction condition is mild, and pharmaceutically acceptable salts of the inhibitor comprise hydrochloride, maleate and the like and can be prepared into tablets, capsules or injections. The inhibitor has high selectivity to CDK6 kinase, can effectively inhibit HR < + > / HER2-breast cancer cell proliferation and overcome drug resistance, has low toxic and side effects, and has significant clinical application value.

The present invention provides a method for preparing natural product dysoxylactam A and its analogues, which relates to the technical field of organic synthesis. The synthetic route starts from aldehydes with different substitutions, constructs four consecutive chiral centers through two aldol condensation reactions, and then through sulfonylation reaction, borohydride reduction, deprotection, protection of hydroxyl protecting groups, and esterification reaction with amino acids, all chiral centers of the target molecule are constructed. Finally, through amide reaction, ring-closing metathesis reaction and hydrogenation reduction reaction, natural product dysoxylactam A and its analogues are successfully obtained. This synthetic method has a high overall yield, simple steps, easy derivatization, low operation requirements, can be prepared in large quantities, and has broad application and development prospects.

The application discloses a catalyst for preparing high-level unsaturated aldehyde through hydroxy aldehyde condensation reaction and a preparation method thereof. Specifically relates to a method for preparing propylene aldehyde through hydroxy aldehyde condensation reaction of a mixed solution of formaldehyde and acetaldehyde, in which, a basic metal is loaded on a modified CeO2 carrier; the reaction is carried out in a fixed bed under normal pressure; the catalyst provided by the application is cheap, and the preparation method is simple, efficient, and has the characteristics of high conversion rate of acetaldehyde in the reaction process, the highest conversion rate can reach 95%, and the selectivity of propylene aldehyde can reach 70%.

The invention belongs to the field of catalysis, and provides an Nb-based composite oxide supported metal catalyst, a preparation method and an application of the Nb-based composite oxide supported metal catalyst in preparation of aviation oil through hydrodeoxygenation. The catalyst comprises a dual carrier of gamma-Al2O3 and Nb2O5 (or NbOPO4), and one or more hydrogenation active metals. The hydrodeoxygenation catalyst provided by the invention has good acidity and hydrogenation performance under the interaction of the two carriers, and the acidity and hydrogenation performance are proved to be superior to those of an original single-carrier catalyst through characterization; the performance of the catalyst in hydrodeoxygenation of a biomass derivative aldol condensation product (a long-chain oxygen-containing compound) to prepare aviation oil is far superior to that of a single-carrier catalyst with the same metal loading capacity.