28 results about "Benzyl bromide" patented technology

The invention relates to the technical field of benzyl bromide preparation and discloses a benzyl bromide preparation device and method.The benzyl bromide preparation device comprises a stirring kettle, a heating box is fixedly connected to the outer wall of the stirring kettle, an isolation sleeve is fixedly connected to the inner wall of the stirring kettle, a water inlet pipe is fixedly connected to the upper surface of the heating box, and a water outlet pipe is fixedly connected to the lower surface of the heating box; one end of the water inlet pipe penetrates through the surface of the heating box and is fixedly connected with a water pump, a supporting plate is fixedly connected into the heating box, the water pump is installed on the surface of the supporting plate, and the middle of the heating box is connected with a heating assembly. The bottom of the isolation sleeve is connected with a temperature measuring assembly, and the inner wall of the isolation sleeve is connected with a scraping assembly. According to the preparation device and the preparation method of the benzyl bromide, reaction materials in the stirring kettle can be uniformly heated, so that the reaction uniformity is improved, and an overheating or supercooling phenomenon of a local area is avoided.

This invention discloses a cellulose mixed ester and its preparation method, comprising the following steps: S1, dissolving cellulose in a solvent, adding an etherification protecting agent and reacting, then adding benzyl bromide and reacting to obtain a first intermediate product; S2, dissolving the first intermediate product in an organic mixed solution and reacting to obtain a second intermediate product, 3-o-benzyl cellulose; S3, reacting the second intermediate product with an acylation agent A under the action of a catalyst to obtain a third intermediate product; S4, removing the benzyl group from the third intermediate product to obtain a fourth intermediate product; S5, acylating the fourth intermediate product with an acylation agent B under the action of a catalyst to obtain the final product, 3-o-B-acyl-2,6-di-o-A-acyl cellulose. This invention successfully achieves the selective esterification preparation of cellulose mixed esters by constructing a solvent dissolution and etherification protecting system, an organic solution reaction system, and an acylation alkaline composite catalyst system in a synergistic manner. More importantly, it achieves a high product yield and a relatively fast reaction process.

This invention relates to the field of oilfield chemical additives technology, and discloses a method for preparing a 1-benzyl-10-phenylpyrrolo[1,2-a:3,4-b']dipyrazine-1-onium type quaternary ammonium salt high-temperature acidizing corrosion inhibitor. The method uses 2,2'-piperazine as the starting material, which undergoes a quaternization reaction with benzyl bromide to obtain a quaternary ammonium salt intermediate. The obtained intermediate undergoes an oxidative cyclization reaction with benzaldehyde and manganese dioxide in a dichloromethane system. After separation, drying, and purification, the target product is obtained. The preparation process of this invention is simple and easy to control, the product is easy to purify, and it is suitable for industrial production. It exhibits good synergistic effects with additives, excellent water solubility and compatibility, can stabilize and protect steel, reduce construction risks, and is suitable for various high-temperature acidizing operations.

The application provides a series of monomolecular resin photoresists based on polybenzyl bromide or polybenzyl iodine and a preparation method and application thereof, and the monomolecular resin can be used as a main body material of the photoresist. Raw materials are cheap and easy to obtain, and the synthesis process is simple. The compound provided by the application takes adamantane as a core unit, is externally connected with multiple benzyl bromide or benzyl iodine groups, and the core structure of adamantane and benzene ring and the introduction of bromine atoms or iodine atoms can maximize the sensitivity and etching resistance of the photoresist.

This invention discloses a method for preparing high-purity quartz sand from quartz ore, relating to the field of high-purity quartz sand processing. First, a quaternized cation reagent is prepared using benzyl bromide and N,N-dimethyldodecylamine as raw materials. The adsorption of this self-made collector on the quartz surface is the result of the combined effects of electrostatic attraction and multiple forms of hydrogen bonding. The addition of quaternary ammonium and polyhydroxy groups allows for strong physical adsorption of quartz without the need for strong acids. Furthermore, a stable filler layer is formed on the quartz surface, thereby improving the collection effect of the quartz sand. Secondly, the preparation process of this invention is as follows: coarse washing – coarse crushing – direct high-temperature bursting water quenching – medium crushing – microwave heating – fine crushing – acid leaching – magnetic separation – flotation – drying. A segmented, step-by-step treatment is adopted, using different treatment methods for different particle sizes of quartz sand, which is beneficial for removing inclusions in the quartz and results in a larger surface area and better effect compared to acid leaching. The quartz sand prepared by this invention exhibits high purity.

The invention provides an ultraviolet light grafting modified UHMWPE fiber, a fiber reinforced composite material and a preparation method and application of the UHMWPE fiber and the fiber reinforced composite material. The preparation method of the ultraviolet light grafting modified UHMWPE fiber comprises the following steps: (1) grafting Diazirine on the UHMWPE fiber: preparing absolute ethyl alcohol and 4-[3-(trifluoromethyl)-3H-bis (aziridin-3-yl) benzyl bromide (Diazirine) into a Diazirine ethanol solution; the UHMWPE fiber is immersed in a Diazirne ethanol solution, the surface of the fiber is fully wetted, the fiber is naturally aired, the two faces of the fiber are irradiated through an ultraviolet light source, and a UHMWPE-Dia fiber is obtained; (2) grafting the UHMWPE-Dia fiber with PEI: dissolving polyethyleneimine (PEI) in a solvent absolute ethyl alcohol to prepare a PEI solution, putting the UHMWPE-Dia fiber obtained in the step (1) and the PEI solution into a sealed container, and carrying out horizontal mechanical shaking for reaction; after the reaction is finished, the fiber is flatly laid and dried to remove the solvent absolute ethyl alcohol, and the UHMWPE-Dia-PEI fiber is obtained. The fiber reinforced composite material comprises epoxy resin, an amine curing agent and ultraviolet grafting modified UHMWPE (Ultra High Molecular Weight Polyethylene) fibers.

The invention discloses a preparation method of a luminescent compound. The preparation method comprises the following steps: step 1, reducing a raw material a by a reducing agent to generate a compound b; 2, reacting the compound b with benzyl bromide to generate a compound c; 3, reacting the compound c with methyl dithioacetate under photocatalysis to generate a target product compound d; according to the present invention, the reaction conditions are mild, the green reaction modes such as photocatalysis are adopted, the good yield can be obtained while the mild reaction conditions are ensured, the method is suitable for the luminescent substrates with various structures, and the application range is expanded.

The application discloses a selenium-substituted hemicyanine dye precursor and a synthesis method and application thereof, and belongs to the fine chemical field. The structure of the selenium-substituted hemicyanine dye precursor is shown in a general formula I. In the general formula I, R1 is one of H, a phenyl group, a p-phenyl benzyl chloride, a p-phenyl benzyl bromide, SO3R4, COOR4 or C1-C 12 alkyl; R2 is C, S or Se; R3 is one of H, a phenyl group or C1-C 12 alkyl; R4 is H or C1-C 12 alkyl; and Y is Cl, Br or I. The application provides a selenium-substituted hemicyanine dye precursor, which has near-infrared absorption and emission spectral performance and high active oxygen generation capacity, and provides an ideal platform for constructing dye photosensitizers.

The invention discloses a method for preparing 4-cyanobenzyl bromide through continuous flow photocatalysis, and belongs to the field of organic synthesis. The preparation method comprises the following steps: by taking p-toluenitrile as a raw material, dissolving the p-toluenitrile in an organic solvent, then adding a bromination reagent, and carrying out photocatalytic bromination reaction to obtain the 4-cyanobenzyl bromide. The method disclosed by the invention is mild in catalytic reaction process condition, simple to operate and few in by-products, and the obtained product is high in purity and stable in performance. The method aims at the defects of a traditional synthesis process, does not need complex operation steps, is suitable for small-scale synthesis in a laboratory, can meet the requirements of industrial large-scale production, and has a wide application prospect.

The invention provides a preparation method of a key intermediate of a gemfibrozil impurity A, and belongs to the technical field of chemical synthesis. According to the invention, a brand-new synthetic route of the gemfibrozil impurity A is designed firstly, and efficient preparation methods of three key intermediates are provided on the basis of the brand-new synthetic route. Specifically, the preparation method comprises the following steps: firstly, reacting with propionyl chloride in a 1, 2-dichloroethane environment under the catalysis of aluminum trichloride, and cooling, layering and drying a product to obtain a first intermediate; taking the first intermediate as a raw material, reacting with benzyl bromide in a DMF (Dimethyl Formamide) environment by taking potassium carbonate as an acid-binding agent, collecting an organic phase, dissolving with methanol, carrying out reduction reaction by using sodium borohydride under the catalysis of cerium chloride heptahydrate, and collecting to obtain a second intermediate; taking the second intermediate as a raw material, dissolving the second intermediate in methylbenzene, and performing dehydration reaction under the catalysis of TsOH.H2O to obtain a third intermediate; on the basis of the three intermediates, efficient synthesis of the gemfibrozil impurity A can be achieved, the synthesis route is short, and the process efficiency is high.

The application provides a fluorescent probe based on a cinnamic acid derivative as well as a synthesis method and application thereof, and relates to the technical field of synthesis of specific probes. The fluorescent probe is prepared by introducing benzyl bromide into the hydroxyl group of a modified structure compound FHA using p-hydroxycinnamic acid as raw material, and a novel bifunctional fluorescent probe capable of specifically detecting Al 3＋ and N2H4 is developed. The application overcomes the defects of the prior art, the probe can specifically detect Al 3+ and N2H4, and has the characteristics of low detection limit, short response time, wide pH application range and the like; the probe has the characteristics of good biocompatibility, small toxicity, good optical properties and the like, and can be applied to cell imaging experiments.

The invention provides a synthetic method of a gemfibrozil impurity A, and belongs to the technical field of chemical synthesis. According to the technical scheme, gemfibrozil is used as an initial raw material and firstly reacts with propionyl chloride in a 1, 2-dichloroethane environment under the catalysis of aluminum trichloride, a product reacts with benzyl bromide in a DMF environment by taking potassium carbonate as an acid-binding agent, an organic phase is collected and dissolved with methanol, and then reduction reaction is performed with sodium borohydride under the catalysis of cerium chloride heptahydrate to obtain gemfibrozil. Collecting to obtain an oily liquid compound, dissolving the oily liquid compound in toluene, carrying out a dehydration reaction under the catalysis of TsOH.H2O, carrying out a hydrolysis reaction on the reaction product in an isopropanol and sodium hydroxide system, carrying out reduced pressure distillation to remove isopropanol, carrying out acid adjustment, extracting with ethyl acetate, drying with sodium sulfate, filtering, concentrating to obtain a white solid, and finally refining and purifying to obtain the 2-(2, 4-dichlorophenyl)-1, 2, 3, 4, 5-tetramethyl-1, 3-pentanediol. A gemfibrozil impurity A finished product is obtained. The method is short in synthetic route, high in process efficiency, convenient to refine and purify and high in yield and purity, and has outstanding technical advantages.

The invention discloses a preparation method of phentolamine EP impurity acid salt, which comprises the following steps: (1) taking a compound I resorcinol and a compound II p-toluidine as raw materials, and performing dehydration reaction to obtain an intermediate product III; (2) carrying out nucleophilic substitution reaction on the intermediate product III and benzyl bromide to generate an intermediate product IV; (3) carrying out nucleophilic substitution reaction on the intermediate product IV and ethyl bromoacetate to obtain an intermediate product V; (4) carrying out ester amidation reaction on the intermediate product V and N-tert-butyloxycarbonyl-1, 2-ethylenediamine to obtain an intermediate product VI; and (5) taking the intermediate product VI, and carrying out deprotection reaction to obtain a final product VII, wherein X represents hydrochloric acid, sulfuric acid, acetic acid, formic acid or trifluoroacetic acid. The purity of the prepared phentolamine EP impurity acid salt reaches 99% or above, the reaction yield is high, a test sample is provided for phentolamine research, and the phentolamine EP impurity acid salt has important research value in clinical pharmacokinetic research.

The invention belongs to the field of rubber materials, and provides a rubber composition for a tire steel wire belt layer and a preparation method thereof, and the rubber composition comprises 70-90 parts of natural rubber, 20-40 parts of epoxidized natural rubber, 5-7 parts of a tackifying system, 50-65 parts of carbon black, 2-5 parts of an anti-aging agent, and 4-6 parts of a sulfur system. The tackifying system is prepared through a reaction of benzimidazole, a thiuram compound and omega-brominated fatty acid benzyl ester, and the omega-brominated fatty acid benzyl ester is prepared through a nucleophilic substitution reaction of omega-brominated fatty acid and benzyl bromide. Benzimidazole and a thiuram compound are bridged through a flexible aliphatic chain to form a tackifying system molecule, and the molecule can be chelated with copper / zinc / iron and other metal ions on the surface of a steel wire through a benzimidazole part, so that the initial bonding strength between rubber and the steel wire is improved; the thiuram part improves the interface stress distribution of the steel wire belt layer rubber and the steel wire, and the bonding performance of the steel wire cord fabric layer is improved.

The invention belongs to the technical field of organic synthesis, and particularly relates to a preparation method of absolute chiral 2-hydroxyhexahydro-1H-pyridine cyclo-7a-formic acid. The preparation method comprises the following steps: reacting 1-Boc-4-hydroxypyrrolidine-2-formic acid with benzyl bromide to obtain a first intermediate product; reacting the first intermediate product with 1, 3-dibromopropane to obtain a second intermediate product; reacting the second intermediate product with trifluoroacetic acid to obtain a third intermediate product; adjusting the pH value of the aqueous solution of the third intermediate product to be greater than or equal to 11 to obtain a fourth intermediate product; reacting the fourth intermediate product with a chiral agent to obtain a fifth intermediate product; and carrying out a reaction on the fifth intermediate product under a hydrogen condition to obtain the absolute chiral 2-hydroxyhexahydro-1H-pyridine cyclo-7a-formic acid. The absolutely chiral 2-hydroxyhexahydro-1H-pyridine cyclo-7a-formic acid product is prepared by reasonably optimizing the reaction process and adopting the simple reaction process, and is suitable for industrial application.

The present application relates to a kind of cation macrocycle photosensitizer and its preparation method and application;Through triphenylamine derivative and p-benzyl bromide synthesis four cation macrocycle 1 molecule, 1 can be used as photosensitizer, the molecule can be through I / II type light reaction path to produce active oxygen, and under the condition of oxygen deficiency, biological molecule (NADH, BH4) is damaged to a large extent.In addition, further through the acylhydrazone bond of pH response, the polyethylene glycol (PEG) chain is modified on the molecule, obtains polyethylene glycol modified four cation macrocycle 1-PEG, through macrocyclic cation cavity, load tumor drug, self-assembly forms supramolecular nanoparticle, realizes the combined treatment of photodynamic and drug, system has remote operation and non-invasive, with drug release and acylhydrazone bond break, fluorescence emission intensity also gradually enhances, can be effectively navigated by fluorescence imaging drug treatment to tumor, thus it has wide application prospect in cancer diagnosis and treatment.

The application discloses a non-hydrogen-evolution non-aqueous electrolyte zinc-bromine battery, which comprises a positive electrode, a negative electrode, an electrolyte and a diaphragm. The positive electrode is a porous conductive support electrode, and the surface of the positive electrode is coated with a composite slurry containing a bromine complexing agent and activated carbon; the negative electrode is a zinc foil; the electrolyte is a non-aqueous organic electrolyte, which comprises a mixed solvent of acetonitrile and tetrahydrofuran, zinc bromide main salt, lithium bis-trifluoromethanesulfonimide or lithium bis-fluoromethanesulfonimide conductive salt and an alkyl or benzyl bromide ammonium cationic surfactant complexing agent. The application adopts an aprotic organic solvent, avoids the electrolytic reaction of water, solves the hydrogen evolution problem of a traditional water-based zinc-bromine battery, eliminates the safety hazard, and significantly improves the solubility and ionic conductivity of zinc bromide in a mixed solvent system. The complexing agent in the positive electrode and the electrolyte can effectively complex bromine and reduce self-discharge. The coulombic efficiency of the battery is stable at more than 92%, the capacity retention rate is greater than 90% after 100 cycles, and the battery exhibits excellent safety performance and cycle stability.

The invention belongs to the technical field of biomedicine synthesis, and particularly relates to the technical field of chemical synthesis of natural drugs / prodrugs for controlling metabolic abnormalities such as blood sugar and blood fat. The invention provides a preparation method of a cholic acid derivative. The preparation method comprises the following steps: adding benzyl bromide into an alkaline solution containing cholic acid to obtain benzyl cholate; the method comprises the following steps: adding a dichloromethane solution containing acyl chloride into a dichloromethane solution containing benzyl cholate and 4-dimethylaminopyridine under protective gas to obtain a colorless oily product; and introducing hydrogen into the absolute ethyl alcohol in which the colorless oily product is dissolved to obtain the cholic acid derivative. The chemical synthesis of the cholic acid derivative is realized.

The invention provides a fluorescent probe based on a cinnamic acid derivative as well as a synthesis method and application of the fluorescent probe, and relates to the technical field of synthesis of specific probes. The fluorescent probe is a novel bifunctional fluorescent probe capable of specifically detecting Al < 3 + > and N2H4, which is developed by taking p-hydroxycinnamic acid as a raw material and introducing benzyl bromide into a hydroxyl site of a modified structural compound FHA. The probe overcomes the defects in the prior art, can specifically detect Al < 3 + > and N2H4, and has the characteristics of low detection limit, short response time, wide pH application range and the like; and the probe has the characteristics of good biocompatibility, low toxicity, good optical property and the like, and can be applied to cell imaging experiments.

The invention discloses a coating method of an electrode material, which comprises the following steps: (1) olefin-substituted imidazole and halogenated hydrocarbon are mixed for an addition reaction to form a quaternary ammonium salt type ionic liquid monomer, and the halogenated hydrocarbon is one or a mixture of several of 3-bis (bromomethyl) benzene, 1, 3-bis (bromoethyl) benzene, 1, 2-dichloroethane and benzyl bromide; (2) thermally initiating the quaternary ammonium salt type ionic liquid monomer, and carrying out polymerization reaction to form a diazolium type polymeric ionic liquid; and (3) mixing the diazolium type polymeric ionic liquid and the electrode material, and calcining to form a carbon coating layer outside the electrode material. The coating material is prepared firstly, and during coating, the electrode material is directly mixed with the coating material, so that element doping is reduced, the capacity and the cycling stability are improved, the types of the electrode materials are not limited, and the application range is wide.

This invention belongs to the field of membrane material technology and discloses a high-flux, acid-resistant polyquaternary ammonium nanofiltration membrane and its preparation method. The method includes: (1) coating an aqueous solution containing cyclic tertiary nitrogen oligomers onto a porous support substrate membrane, wetting it, and then removing excess liquid; (2) subsequently coating the surface of the material obtained in step (1) with a hexane solution containing benzyl bromide, wetting it so that the tertiary nitrogen atoms on the cyclic tertiary nitrogen oligomers undergo a quaternization reaction with the benzyl bromide, gradually forming a dense separation membrane at the water-hexane interface; after the reaction is completed, it is dried to obtain the nanofiltration membrane. The nanofiltration membrane prepared by this invention overcomes the disadvantages of traditional polyquaternary ammonium membranes, which require several hours to prepare and have low permeability. A defect-free nanofiltration separation membrane can be prepared in just 1 minute. After soaking in 1M sulfuric acid for 30 days, it can still maintain high permeability and rejection rate, showing good application prospects.

A high stability formulation in the form of an aqueous mixture is disclosed. The formulation containing a quaternary ammonium organosilane hydrolysate includes the structure A(CH3)2N+(CH2)3Si(OZ)3-n(OH)n, wherein “A” is a saturated or unsaturated aliphatic chain having 12 to 18 carbons, “n” is an integer ranging from 0 to 2, “Z” is methyl or ethyl. A method to obtain the formulation includes a first reaction in which the tertiary amine group having the structure A(CH3)2N is quaternized by alkylation with a reactant having the structure (CH2)3Si(OR)3X, wherein X is halogen. Then, a second reaction is performed in which the tertiary amine remaining unreacted in the first reaction is quaternized with one or more supplementary reactants selected from benzyl chloride, benzyl bromide, benzyl iodide, vinyl benzyl chloride, vinyl benzyl bromide, vinyl benzyl iodide, epichlorohydrin, epibromohydrin, epiiodohydrin, chloroethanoic acid, bromoethanoic acid, iodoethanoic acid, and sultones, preferably 1,3-propane sultone or 1,4-butane sultone.

The invention provides a preparation method of an aboxitinib intermediate, which comprises the following specific preparation steps: (1) carrying out substitution reaction on 3-oxocyclobutylamine hydrochloride and propyl sulfonyl chloride to obtain an intermediate 24; and (2) carrying out substitution reaction on the intermediate 24 obtained in the step (1) and benzyl bromide to obtain the aboxitinib intermediate 21. According to the invention, the 3-oxocyclobutylamine hydrochloride is selected as a starting material, and the aboxitinib intermediate 21 is generated through a two-step reaction, so that the process route is greatly simplified, and the production cost is reduced; moreover, the propyl sulfonyl chloride substitution reaction for preparing the aboxitinib is advanced to the first step, so that the propyl sulfonyl chloride is effectively prevented from being subjected to a side reaction with 7-site N on a pyrrolo [2, 3-d] pyrimidine ring, the column chromatography purification step is omitted, the production efficiency and the overall yield are improved, the amplified application is safer, and the method is more suitable for industrial production.

The invention relates to an enadostat key intermediate and application of the enadostat key intermediate to preparation of enadostat, and belongs to the field of medicine preparation. The invention discloses preparation of key intermediate compounds 6 and 7, which specifically comprises the following steps: reacting a compound 1 with cyanoacetate under the action of an acid-binding agent to obtain a compound shown as a formula 6, and then reacting with benzyl chloride or benzyl bromide to obtain the intermediate 7. And when the method is used for the following reaction, the high-purity enadostat can be obtained without excessive post-treatment.

The invention discloses a cellulose mixed ester and a preparation method thereof, and the preparation method comprises the following steps: S1, dissolving cellulose in a solvent, then adding an etherification protective agent for reaction, and then adding benzyl bromide for reaction to obtain a first intermediate product; s2, dissolving the first intermediate product in an organic mixed solution for reaction to obtain a second intermediate product 3-o-benzyl cellulose; s3, reacting the second intermediate product with an acylating agent A under the action of a catalyst to obtain a third intermediate product; s4, removing benzyl from the third intermediate product to obtain a fourth intermediate product; and S5, under the action of a catalyst, acylating the fourth intermediate product and an acylating agent B to obtain a final product 3-o-B acyl-2, 6-di-o-A acyl cellulose. According to the method, the solvent dissolution and etherification protection system, the organic solution reaction system and the acylation alkaline composite catalyst system are constructed to cooperate with one another, so that the selective esterification preparation of the cellulose mixed ester is successfully realized, and more importantly, the product yield is relatively high, and the reaction process is relatively fast.

This invention discloses a bipyrrole-based axially chiral phase transfer catalyst, its preparation method, and its application, belonging to the technical field of axially chiral phase transfer catalysts. The axially chiral compound (S)-1,9-diphenyl-5-((S)-1-phenylethyl)-5,6-dihydro-4H-dipyrrolo[1,2-b:2',1'-g][1,2,5]triazacycloheptane-3,7-dicarboxylic acid diethyl ester is used as a nucleophile to attack the partially positively charged carbon atom in the benzyl bromide reagent, replacing its bromide ion to generate a quaternary ammonium ion intermediate. The bromide ion attack causes the C-N bond to break, and the phenylethyl group on the quaternary ammonium ion intermediate detaches, forming a chiral tertiary amine with a benzyl group. Subsequently, it undergoes a quaternization reaction with excess benzyl bromide to obtain the chiral phase transfer catalyst. The prepared catalyst exhibits good catalytic activity in the [3+2] cycloaddition reaction of 2-(morpholine-4-carbonyl)allyl benzenesulfinate with phenylacryloylbenzene. The preparation method is simple and has broad application prospects.

The utility model discloses a kind of production devices of benzyl bromide, it is related to benzyl bromide production technical field, the inlet of reaction kettle is respectively communicated with formic acid tank, sulfuric acid tank, benzyl alcohol tank, purified water tank and bromine tank by pipeline, the top gas phase outlet of reaction kettle is communicated with reflux condenser by pipeline, the bottom outlet of reaction kettle is communicated with first liquid separator tank by pipeline, the oil phase outlet of first liquid separator tank is communicated with benzyl bromide product tank by pipeline.Using benzyl alcohol and bromine as main raw material, benzyl bromide is prepared by reaction, reaction selectivity is higher, by-product is significantly reduced, solve the problem that conventional toluene free radical halogenation method has many by-products, purification is complex, can directly obtain higher purity crude product by liquid separation initially.

The invention relates to a preparation method of a chiral hexahydropyridazine intermediate, which comprises the following steps: by taking simple and easily available 3-substituted pyridazine (compound I) as a raw material, screening through a series of asymmetric catalytic hydrogenation conditions to obtain an optimal reaction condition, and under the condition, synthesizing the chiral hexahydropyridazine intermediate. Various 3-site and benzene ring substituted N-benzylpyridazine quaternary ammonium salts are reduced into chiral hexahydropyridazine products, and the enantioselectivity of the C3 site of the products is excellent. Brominated 1-benzyl-3-methylpyridazinium is selected as a substrate, and the N-N fused pyrazolone skeleton can be prepared with high enantioselectivity and high yield through asymmetric catalytic hydrogenation, acylation, debenzylation, acylation and Aldol condensation reactions.