900 results about "Pentene" patented technology

Herbicidally active 3-phenylisoxazoline-5-carboxamides of cyclopentenylcarboxylic acid derivativesThe invention relates to 3-phenylisoxazoline-5-carboxamides of cyclopentenylcarboxylic acid derivatives of the general formula (I) and their agrochemically acceptable saltsand to their use in the crop protection sector.

The invention belongs to the technical field of polyurethane waterproof coatings, and particularly relates to a single-component fluorine-free high-hydrophobicity polyurethane waterproof coating and a preparation method thereof, and the single-component fluorine-free high-hydrophobicity polyurethane waterproof coating comprises the following raw materials by weight: 60-80 parts of composite polyether polyol; 20 to 40 parts of silane modified polyether polyol; 11 to 17 parts of diisocyanate; 2-5 parts of a chain extender; 50 to 70 parts of a plasticizer; 50 to 70 parts of filler; 0.15 to 0.2 part of a catalyst; and 3-5 parts of an auxiliary agent. A polyoxypentene ether chain segment, a castor oil-based structure and a silane group are introduced into the molecular structure of the waterproof coating through chemical modification, the intrinsic hydrophobic and mechanical properties of the material are improved, the migration defect caused by addition of a hydrophobic agent and silicone oil in a traditional preparation method is overcome, and the invention further provides a preparation method of the waterproof coating.

The invention discloses a preparation method of an optical OCA (Optical Clear Adhesive) and application of the optical OCA in a mobile phone folding screen, and relates to the technical field of optical cement, the optical OCA is prepared from the following raw materials in parts by weight: 50 parts of acrylate prepolymers, 2-4 parts of 3-allyl-2-mercapto-3H-quinazoline-4-ketone, 1-3 parts of diallyl disulfide, 1-3 parts of 3-[N, N-dimethyl formamide], 1-3 parts of 2, 3, 5-trimethyl-1, 3-pentanediol monoisobutyronitrile, 1-3 parts of 2, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3 The preparation method comprises the following steps: adding 3-5 parts of N, N-dimethyl-[2-(2-methylpropane-2-enoyloxy) ethyl] ammonium] propane-1-sulfonic acid inner salt, 1-3 parts of allyl succinimido carbonate, 2-4 parts of dicyclopentene methacrylate, 1-3 parts of 1, 3, 5-triacryloyl hexahydro-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5- The invention relates to a graphene quantum dot photoinitiator which is prepared from the following components in parts by weight: 1-3 parts of 1, 3, 5-triazine, 0.8-1.2 parts of a photoinitiator, 1-3 parts of an aziridine cross-linking agent, 1-3 parts of graphene quantum dots, 0.8-1.2 parts of a coupling agent and 40-50 parts of a diluent. The optical OCA adhesive is high in light transmittance and bonding strength, good in weather resistance and excellent in folding resistance.

The invention discloses a synthetic method of glabridin with optical purity, which comprises the following steps: by taking (R)-3-acetoxyl-2-(2, 4-dimethoxyphenyl) propanol and 2-isopentenyl resorcinol as raw materials, carrying out Mitsunobu reaction to obtain a key intermediate compound I, then carrying out hydrolysis and iodination to obtain an intermediate compound II, and then carrying out cyclization to obtain the glabridin with optical purity. Reducing and removing a protecting group to obtain glabridin. By introducing the isopentene side chain, the reaction activity of an olefin functional group is reserved, a key site is provided for subsequent cyclization conversion, the precise spatial configuration of the product is ensured, and finally glabridin with optical purity is prepared. The method is short in route, low in cost, mild in reaction condition and suitable for industrial production.

The invention relates to the technical field of all-solid-state batteries, in particular to air-stable argyrodite type sulfide electrolyte, a preparation method thereof and an all-solid-state battery. The air-stable argyrodite type sulfide electrolyte provided by the invention comprises a sulfide solid electrolyte and a protective layer formed by self-assembly of organic molecules on the surface of the sulfide solid electrolyte, wherein the sulfide solid electrolyte is argyrodite type sulfide solid electrolyte, the general formula of the sulfide solid electrolyte is Li < 7-a > PS < 6-a > X , X is halogen, and a is more than 0 and less than 2; the organic molecule is at least one of 1-methoxyhexane, 2-heptanone, 3-chloropropanol, 4-chlorobenzyl mercaptan, n-amylamine, 5-chloromethyl-1, 3-benzodioxole, chlorophenylmethane and ethylbenzene, and the organic molecule is at least one of 1-methoxyhexane, 2-heptanone, 3-chloropropanol, 4-chlorobenzyl mercaptan, n-amylamine, 5-chloromethyl-1, 3-benzodioxole, chlorophenylmethane and ethylbenzene. According to the air-stable argyrodite type sulfide electrolyte provided by the invention, the stability of the sulfide electrolyte to water can be enhanced, and the ionic conductivity of the sulfide electrolyte can be ensured.

The invention discloses a perovskite solar cell based on buried interface modification and a preparation method and application thereof. The invention relates to an application of 2-(acrylamide) benzoic acid and / or 2-(4-pentenoylamido) benzoic acid in a trans-perovskite solar cell buried interface modifier. According to the invention, 2-(acrylamide) benzoic acid and / or 2-(4-pentenylamido) benzoic acid are / is used as a buried interface modifier, such molecules take benzoic acid as an anchoring group, and through the synergistic effect among carboxyl, amido and carbon-carbon double bonds, the defects at the thin film grain boundary of the hole transport layer and the perovskite layer are reduced; according to the invention, the NiOX thin film is introduced into the small molecules, and the alkyl chain is further introduced into the small molecules and can effectively fill small recesses and holes in the NiOX thin film, so that the flatness of the NiOX thin film is improved, a compact and compact modification layer is formed, the morphology of the perovskite layer thin film is further regulated and controlled, and the photoelectric conversion efficiency of the perovskite solar cell is improved.

Methods for treating immune thrombocytopenia comprising administering at least one compound chosen from (R)-2-[3-[4-amino-3-(2-fluoro-4-phenoxy-phenyl)pyrazolo[3,4-d]pyrimidin-1-yl]piperidine-1-carbonyl]-4-methyl-4-[4-(oxetan-3-yl)piperazin-1-yl]pent-2-enenitrile (rilzabrutinib) and pharmaceutically acceptable salts thereof are disclosed.

The invention discloses a modified graphene antistatic fiber and a preparation method thereof, and relates to the technical field of chemical fibers. When the modified graphene antistatic fiber is prepared, polyethylene glycol terephthalate, an ultraviolet absorption monomer and dimethyl (vinyl) silane react to prepare modified polyester; the preparation method comprises the following steps: polymerizing thiophene, hydantoin thiophene and 3-vinyl thiophene, and coating the phase change microcapsule with the polymerized thiophene, hydantoin thiophene and 3-vinyl thiophene to prepare a pre-modified phase change microcapsule; reacting the pre-modified phase change microcapsule with sodium hypochlorite to obtain a modified phase change microcapsule; the pre-modified graphene and 5-chloro-1-pentene are subjected to a reaction, and modified graphene is prepared; preparing a spinning solution from the modified polyester, the modified phase change microcapsules, the modified graphene, chloroplatinic acid and N, N-dimethylformamide, and performing wet spinning to obtain the modified graphene antistatic fiber. The modified graphene antistatic fiber prepared by the invention has excellent anti-aging, antibacterial, flame-retardant, antistatic, warm-keeping and mechanical properties.

The invention discloses Klebsiella and application thereof, and belongs to the technical field of microorganisms. According to the invention, firstly, a strain LLMJ-DNXJ-01 with high yield of tannase is screened from wine-making yeast, the identification result shows that the strain belongs to klebsiella, then the tannase activity of the strain is investigated, and the result shows that the enzyme activity reaches 8.8 + / -0.02 U / mL. In addition, the invention also investigates the application of the strain in degrading sorghum tannin, the sorghum tannin degradation rate reaches 34.95%, and isoamyl alcohol, isopentenol, caryophyllene, phenethyl alcohol, 4-vinyl guaiacol and other volatile aroma substances with Daqu characteristics can be generated through fermentation. Therefore, by integrating the tannase production capability of the strain LLMJ-DNXJ-01 and the sorghum tannin degradation and fermentation aroma production capability, the strain has relatively good development potential in the aspects of manufacturing of reinforced yeast for making hard liquor and quality improvement and aroma enhancement of white spirit.

A technology for preparing glutaraldehyde through cyclopentene oxidation belongs to the technical field of organic synthesis, glutaraldehyde is prepared through cyclopentene oxidation by adopting a photocatalysis-electrocatalysis synergistic catalyst g-C3N4 / TiO2 (at) Au-Co / N-G. The catalyst is of a unique core-shell structure, is stable in property, promotes an oxygen reduction reaction in a catalysis technology, and has good catalytic activity. The conversion rate of cyclopentene and the selectivity of glutaraldehyde are remarkably improved, and the effect is remarkable.

Methods for treating patients with moderate-to-severe asthma comprising administering a therapeutically effective amount of at least one compound chosen from (R)-2-[3-[4-amino-3-(2-fluoro-4-phenoxy-phenyl)pyrazolo[3,4-d]pyrimidin-1-yl]piperidine-1-carbonyl]-4-methyl-4-[4-(oxetan-3-yl)piperazin-1-yl]pent-2-enenitrile (rilzabrutinib) and pharmaceutically acceptable salts thereof are disclosed.

The invention belongs to the technical field of organic synthesis, and relates to a preparation method of 5, 5-dimethyl-4, 5-dihydroisoxazole. The method comprises the following steps: (1) reacting isopentenal with an oximation agent to obtain a reaction solution containing isopentenal oxime; (2) dropwise adding the reaction liquid into a mixture containing isopentenal and an acid catalyst for reaction to obtain a product; or when the reaction liquid contains water, performing phase splitting on the reaction liquid to obtain an organic phase, and dropwise adding the organic phase into a mixture containing the isopentenal and the acid catalyst for reaction to obtain a product. The method does not produce ketone by-products, and is good in atom economy, high in reaction yield, good in technological process continuity, low in cost, few in materials, simple to operate, mild in reaction condition, low in requirements on production equipment and suitable for large-scale industrial production.

The invention relates to a polycarboxylic acid water reducer and a preparation method thereof, and the water reducer is prepared from the following raw materials: 45 to 55 percent of isopentenyl polyoxyethylene ether, 28 to 35 percent of acrylic acid, 1.5 to 2.5 percent of modifier, 0.3 to 0.5 percent of ammonium persulfate, 0.03 to 0.06 percent of ascorbic acid, 5 to 8 percent of hydroxyethyl methylacrylate, 0.15 to 0.25 percent of 2, 4-diphenyl-4-methyl-1-pentene and the balance of water. The modifier is prepared from the following raw materials: 1, 5-dichloronaphthalene, p-nitrostyrene, dimethyl sulfate, ceric ammonium nitrate and tetramethylpiperidine oxide. The polycarboxylate superplasticizer has excellent neat paste fluidity and fluidity retention capability, has low 1h time-dependent variable slump which is below 18mm and optimally 10mm when applied to concrete, has a water-reducing rate of more than 40% and a gas content of less than 3.8%, and also has more advantages in compressive strength ratio.

The invention relates to the discovery of a biosynthetic gene cluster of an alkaloid, namely, exopoid C, and the biosynthetic gene cluster of the exopoid. A biosynthetic gene cluster exo of an exopoid compound is obtained from a fungus Penicillium sp.HDN14-431 through genome mining, the gene cluster comprises a heme-dependent oxidase gene exoA which is composed of indole dioxygenase and a cytochrome b5 structural domain, a cytochrome P450 enzyme gene exoB and an isopentenyl transferase gene exoC which is composed of indole dioxygenase and a cytochrome b5 structural domain, and the cytochrome P450 enzyme gene exoB and the isopentenyl transferase gene exoC are used as biosynthetic genes of the exopoid compound. All genes in a gene cluster are expressed through an aspergillus nidulans heterologous expression system, two isopentenyl indole alkaloids are obtained in total, and a compound I is a new compound exopoid C. And the compound II, namely the exopoid, is a known compound. The biosynthesis pathway of the compound is reported for the first time.

According to the preparation method of the oral PCSK9 inhibitor intermediate, the used intermediate and the synthesis method of the intermediate, the key intermediates are innovatively designed and synthesized, the operation conditions of the steps are mild, the yield is high, the cost is low, toxic impurities are few, the steps are few, and industrial production is facilitated. The synthesis thought of the oral PCSK9 inhibitor intermediate MK-A is constructed through the key intermediates, the 5-bromo-1-pentene is innovatively used as the starting material, the reaction steps are shortened, the yield is obviously improved, the cost is reduced, and the method is suitable for large-scale production.

Disclosed herein are novel methods for preparing 2-[(3R)-2-[4-amino-3-(2-fluoro-4-phenoxy-phenyl)pyrazolo[3,4-d]pyrimidin-1-yl]piperidine-1-carbonyl]-4-methyl-4[4-(oxetan-3-yl)piperazin-1-yl]-pent-2-enenitrile, including various solvate forms and intermediates thereof. Also disclosed herein are novel solvate forms and intermediates of 2-[(3R)-2-[4-amino-3-(2-fluoro-4-phenoxy-phenyl)pyrazolo[3,4-d]pyrimidin-1-yl]piperidine-1-carbonyl]-4-methyl-4[4-(oxetan-3-yl)piperazin-1-yl]-pent-2-enenitrile.

Methods for treating patients with wAIHA comprising administering at least one compound chosen from (R)-2-[3-[4-amino-3-(2-fluoro-4-phenoxy-phenyl)pyrazolo[3,4-d]pyrimidin-1-yl]piperidine-1-carbonyl]-4-methyl-4-[4-(oxetan-3-yl)piperazin-1-yl]pent-2-enenitrile (rilzabrutinib) and pharmaceutically acceptable salts thereof are disclosed.

The application discloses a preparation method of a hollow fiber exchange membrane and the hollow fiber exchange membrane, and the preparation method comprises the following steps: stirring and melting poly(4-methyl-1-pentene), a diluent, an antioxidant and an anti-volatilization agent at 220 DEG C to 280 DEG C to obtain a casting solution; extruding and spinning the casting solution through a spinneret to form a hollow fiber, then passing through an air gap to enter a cooling liquid to solidify to obtain a semi-finished product membrane; placing the semi-finished product membrane into an extracting agent to remove the diluent in the semi-finished product membrane through extraction; and drying the semi-finished product membrane after the diluent is removed to obtain the hollow fiber exchange membrane. The preparation method of the hollow fiber exchange membrane adds the antioxidant and the anti-volatilization agent into the diluent, solves the problems of discoloration and decomposition of the diluent caused by high temperature during high-temperature mixing and extrusion molding of the casting solution, the size, gas flux and mechanical properties of the prepared membrane are more stable, and the prepared hollow fiber exchange membrane has a better membrane structure and better performance.

The present invention relates to a tobacco flavor base module, flavor and heated cigarette that improve the consistency of puff by puff, and belongs to the field of tobacco flavors and fragrances. The tobacco flavor base module is composed of the following components: 3,4-dimethyl-1,2-cyclopentanedione slow-release flavor, 3,5-dimethyl-1,2-cyclopentanedione slow-release flavor, methylcyclopentenolone slow-release flavor, ethylcyclopentenolone slow-release flavor, furfural slow-release flavor, 5-methylfurfural slow-release flavor, furfuryl alcohol slow-release flavor, 2-methyltetrahydrofuran-3-one slow-release flavor, 4-hydroxy-2,5-dimethyl-3(2H)furanone slow-release flavor, 3-pentene-2-one slow-release flavor, ethyl maltol slow-release flavor, maltol slow-release flavor, 5-methyl-2-furanmethanol slow-release flavor. The present invention prepares the slow-release flavor by making each component into a slow-release flavor and then mixes it as a tobacco flavor base module, which not only improves the consistency of puff by puff during puffing, but also significantly improves the burnt sweet fragrance characteristics of heated cigarettes.

The invention provides a preparation method of 2-pentyl-2-cyclopentenone, and belongs to the technical field of organic synthesis. The preparation method comprises the following steps: carrying out a first-stage isomerization reaction on 2-pentylidene cyclopentanone and a first composite catalyst in a first atmosphere to obtain an intermediate, carrying out a second-stage isomerization reaction on the intermediate and a second composite catalyst in a second atmosphere, and controlling the volume ratio of nitrogen to hydrogen in the first atmosphere and the second atmosphere to obtain the 2-pentylidene cyclopentanone. In the first-stage isomerization reaction, the conversion rate of converting 2-pentylidene cyclopentanone into 2-pentyl-2-cyclopentenone is increased, and in the second-stage isomerization reaction, the use amount of hydrogen in the second atmosphere is reduced, the temperature of the second-stage isomerization reaction is increased, generation of by-products is inhibited, and the yield of 2-pentylidene cyclopentanone is increased. Further, the yield and the purity of the 2-pentyl-2-cyclopentenone can be improved. According to the preparation method, the first-stage isomerization reaction and the second-stage isomerization reaction are continuous reactions, intermittent reactions are not needed, and the preparation method is more suitable for industrial application.

The invention discloses lithium ion diaphragm coating slurry and a preparation method and application thereof.The lithium ion battery diaphragm comprises a base membrane and a coating on the base membrane, the coating comprises a dispersing agent, potassium carboxymethyl cellulose and side-chain modified polyvinylidene fluoride, and the method for preparing the side-chain modified polyvinylidene fluoride comprises the steps that vinylidene fluoride, hexafluoropropylene, (S)-4-pentene-1, 2, 4-triazole-1, 2, 4-triazole-1, 2, 4-triazole-1, 2, 4-triazole-1, 2, 4-triazole-1, 2, 4-triazole-1, 3-triazole-1, 3-triazole-1, 2-triazole-1, the preparation method comprises the following steps: uniformly mixing 1, 2-diol, (S)-3-(trifluoromethyl) adipyl dichloride, an initiator, an auxiliary agent and a solvent, and reacting for 9-12 hours in an inert gas atmosphere at 75-80 DEG C under a stirring condition to obtain a reaction solution; and carrying out spray drying on the reaction liquid to obtain the side chain modified polyvinylidene fluoride. The coating slurry provided by the invention can realize firm bonding between the diaphragm and a pole piece at room temperature, improves the stability and safety of a battery structure, and remarkably reduces the internal resistance of the battery diaphragm at the same time.

The invention discloses a high-temperature-resistant poly (4-methyl-1-pentene) dielectric film with synergistically improved insulating strength and dielectric property and a preparation method and application thereof, and belongs to the field of preparation processes of polymer energy storage dielectric materials. The invention aims to solve the problems that the existing polymer energy storage material is low in energy storage density at high temperature, and the dielectric property and the insulating strength cannot be improved at the same time. The invention provides a method for preparing a norbornene dianhydride grafted poly (4-methyl-1-pentene) film by a two-step method by using poly (4-methyl-1-pentene) particles, norbornene dianhydride and dicumyl peroxide and combining a solution suspension technology with a melt casting extrusion technology and a one-way stretching traction technology. The high-temperature-resistant poly (4-methyl-1-pentene)-based dielectric film prepared by the invention has excellent breakdown strength and dielectric property, and the discharge energy density is as high as 5.92 J / cm < 3 > when the charge-discharge efficiency is greater than or equal to 90% at 150 DEG C.

The invention belongs to the technical field of octafluorocyclopentene gas preparation, and particularly relates to a catalytic synthesis method of octafluorocyclopentene. The method specifically comprises the following step: under the action of a fluorine-chlorine catalyst, carrying out gas-phase catalytic fluorination reaction on 1-chloroheptafluorocyclopentene and anhydrous hydrogen fluoride at 80-120 DEG C to obtain octafluorocyclopentene. The preparation method of the fluorine-chlorine catalyst comprises the following steps: dissolving metal chloride in water, adding a precipitant, and fully stirring for reaction to obtain slurry; filtering the slurry to remove filtrate to obtain a solid, and washing the solid with deionized water until the solid is neutral; adding aluminum nitrate into the washed solid, fully stirring and drying to obtain a precursor of the catalyst; and performing compression molding on the precursor of the catalyst, roasting, and activating to obtain the fluorine-chlorine catalyst. The method is mild in reaction condition and high in catalytic efficiency.

The invention belongs to the technical field of building materials, and particularly relates to a silane modified starch-based polycarboxylate superplasticizer and a preparation method thereof. The water reducing agent is prepared by taking renewable sulfonated starch as a raw material, performing graft modification through vinyltriethoxysilane (A151), introducing active double bonds into starch molecules, and then copolymerizing with monomers such as isopentenol polyoxyethylene ether (TPEG) and acrylic acid. Compared with the prior art, the mixing amount of the vinyltriethoxysilane (A151) is only 1%-5% of the mass fraction of the acrylic acid, the mixing amount is low, and the cost is saved; the water reducing and dispersing performance of the starch-based polycarboxylic acid water reducing agent is improved, and a certain viscosity reducing effect is achieved.

The invention belongs to the technical field of novel material catalysis, and particularly relates to a hollow mesoporous silica supported phosphotungstic acid catalyst and a preparation method and application thereof. According to the invention, the advantages of high specific surface area and regional effect performance of hollow mesoporous silica and the characteristic of adjustable acidity of vacancy heteropolyacid quaternary ammonium salt are innovatively combined, and the cationic surfactant is loaded on the surface of the hollow mesoporous silica, so that the contact surface of raw materials is effectively increased, efficient conversion of reactants is assisted, and the reaction efficiency is improved. The supported catalyst with efficient catalysis and stable performance is obtained. The catalyst can be used for a reaction for preparing glutaraldehyde through heterogeneous catalysis of cyclopentene oxidation, and the reaction condition is mild. Experiments show that under the catalytic system, the cyclopentene conversion rate can reach 90% or above, the glutaraldehyde selectivity is improved to 75% or above, double improvement of the cyclopentene conversion rate and the glutaraldehyde selectivity is successfully achieved, meanwhile, the advantage that the catalyst is easy to separate is achieved, and an efficient solution is provided for industrial application of synthesis of glutaraldehyde through cyclopentene oxidation.

A method for separating and purifying 4MP1 from a mixture containing 4MTP2 and 1-Hexene comprises the following steps: continuously introducing a solution in which 4MTP2, 1-Hexene and 4MP1 with any concentration are dissolved into a simulated moving bed chromatography system as a raw material solution, collecting a high-purity 4MP1 solution from raffinate of the simulated moving bed chromatography system by adopting a metal organic framework material as a stationary phase, and separating the high-purity 4MP1 solution from the raffinate of the simulated moving bed chromatography system. The extraction liquid is a solution containing impurities 4MTP2 and 1-Hexene. The invention provides a brand new method for separating 4MP1 from 4MTP2 and 1-Hexene, and a complete separation scheme is provided for the prior art; in the separation of high-concentration 4MP1, the relative purity of the separated and purified 4MP1 can reach gt; the recovery rate is gt; and in the separation of low-concentration 4MP1, the rectification level is also exceeded, and the method is more suitable for 4MP1 thermosensitive substances.

The invention belongs to the technical field of biomedical materials, and particularly relates to a poly-4-methyl-1-pentene (PMP) gas-blood exchange membrane for an extracorporeal membrane oxygenation (ECMO) system, which realizes a long-acting antithrombotic function through a bionic interface construction technology. The invention aims to provide a bionic antithrombotic PMP gas-blood exchange membrane based on zwitter-ion gradient grafting, and through material and process innovation, the following problems existing in a traditional ECMO gas-blood exchange membrane: an antithrombotic coating is easy to fall off, and the long-term effect is insufficient; the risk of blood injury caused by dependence on heparin or anticoagulants; and the surface modification process destroys the membrane pore structure and air permeability.

The invention discloses a preparation method and application of a catalyst with a high-valence tungsten coordination structure, and the preparation method of the catalyst comprises the following steps: enabling tungstic acid and hydrogen peroxide with specific concentration and proportion to react at a certain temperature to prepare a peroxy tungstic acid solution; dissolving a polydentate organic ligand capable of forming a stable chelation structure with a tungsten center in an organic solvent, mixing the obtained ligand solution with a peroxytungstic acid solution according to a specific ratio, and carrying out a coordination reaction at a certain temperature until the ligand is completely reacted; and finally, carrying out solid-liquid separation, washing and drying to obtain the high-valence tungsten coordination structure catalyst. The catalyst can be used for a reaction for synthesizing glutaraldehyde through cyclopentene oxidation, under the mild condition, hydrogen peroxide serves as a green oxidizing agent, the conversion rate of cyclopentene reaches 90% or above, the selectivity of glutaraldehyde exceeds 60%, the catalyst is stable in structure and can be recycled for 10 times or above, and the problems that in the prior art, a catalyst is difficult to separate, low in activity, poor in stability and the like are solved; the method has a remarkable industrial application value.

The invention belongs to the technical field of organic matter preparation, and particularly relates to a preparation method of 2-pentylcyclopentyl-2-ketene. According to the method, methanol is used as a solvent, sulfonic acid type resin doped with lewis acid is used as a catalyst to catalyze the isomerization reaction of 2-pentylidene cyclopentanone, the catalyst and the methanol solvent can jointly promote the isomerization reaction of 2-pentylidene cyclopentanone, and the catalytic efficiency is high, so that the reaction yield is remarkably increased, and the catalyst cost is reduced; in addition, a fixed bed reactor continuous production mode is adopted, waste salt is prevented from being generated when the acid catalyst is quenched by processes such as HCl / HBr / p-toluenesulfonic acid, and methanol is used as a solvent, so that the byproduct dimethyl ether is simply separated from water and the solvent methanol. In addition, when the sulfonic acid type resin doped with the lewis acid is used for catalyzing the isomerization reaction of 2-pentylidene cyclopentanone, the stability is high, and the service life is long.

The invention discloses a preparation method of 3-chloro-5, 5-dimethyl-4, 5-dihydroisoxazole, which comprises the following steps: taking a hydroxylamine oxygen sulfonic acid aqueous solution and isopentenal as raw materials, carrying out oximation reaction in an organic solvent under an alkaline condition, then directly adding an acid or an organic base catalyst into the reaction system, and reacting for 2-4 hours to obtain 3-chloro-5, 5-dimethyl-4, 5-dihydroisoxazole, thereby obtaining the 3-chloro-5, 5-dimethyl-4, 5-dihydroisoxazole. Under the catalytic action of the catalyst, a cyclization reaction is carried out, after the reaction is finished, an intermediate solution containing 5, 5-dimethyl-4, 5-dihydroisoxazole is obtained, and the next step is directly carried out; and carrying out a chlorination reaction by taking the intermediate solution as a raw material and sodium hypochloride or chlorine as a chlorination reagent, and after the reaction is finished, carrying out post-treatment to obtain the 3-chloro-5, 5-dimethyl-4, 5-dihydroisoxazole. The hydroxylamine oxygen sulfonic acid is used for enabling the isopentenal to be subjected to oximation reaction under the alkaline condition, then cyclization is carried out under the catalytic action of acid or alkali, the 5, 5-dimethyl-4, 5-dihydroisoxazole is generated, and the process has the advantages that the yield is high, the production steps are simplified, and the production cost is reduced.