34 results about "Chlorobenzoic Acids" patented technology

The invention relates to a dapagliflozin impurity and a preparation method thereof, 5-bromo-2-chlorobenzoic acid (IV) is used as a raw material, (5-bromo-2-chlorphenyl) (4-ethyoxyl phenyl) ketone (III) is prepared through chlorination and Friedel-Crafts acylation, (5-bromo-2-chlorphenyl) (4-ethyoxyl phenyl) methanol (II) is obtained through reduction, and the benzhydryl ether impurity (I) is obtained through condensation under the catalysis of iodine. The preparation method has the advantages of simple operation, low cost, easily available raw materials and good product purity.

The application belongs to the technical field of medicine synthesis, and particularly relates to a preparation method of furosemide. The preparation method of furosemide comprises the following steps: chlorosulfonation: reacting chlorosulfonic acid and 2,4-dichlorobenzoic acid, hydrolyzing, filtering, and obtaining 2,4-dichloro-5-sulfonyl chlorobenzoic acid; amination: adding 2,4-dichloro-5-sulfonyl chlorobenzoic acid into ammonia water, reacting, neutralizing, filtering, purifying, and obtaining 2,4-dichloro-5-sulfonamidobenzoic acid; condensation: reacting 2-furfurylamine and 2,4-dichloro-5-sulfonamidobenzoic acid, and obtaining furosemide crude product; decolorization: adding the furosemide crude product into a saturated sodium bicarbonate solution, adding activated carbon for decolorization, neutralizing, and crystallizing, and thus furosemide product is obtained. The raw material used in the application is easy to obtain and low in price, the comprehensive reaction period is short, the amount of hazardous waste generated is small, the prepared furosemide is high in purity and high in total yield, the comprehensive cost of the whole preparation process is low, and the application is suitable for industrial production.

This invention belongs to the field of organic electrochemical synthesis and microchemical technology, and relates to a method for preparing 2-chlorobenzoic acid by electrochemical reduction debromination in a continuous flow microreactor. The method includes: dissolving 3-bromo-2-chlorobenzoic acid, a supporting electrolyte, and a proton source in a polar aprotic solvent to prepare a cathode reaction solution; continuously feeding this solution into the cathode channel of a microchannel electrochemical reactor using a metering pump, while simultaneously pumping the anolyte into the anode channel; connecting a DC power supply and conducting a selective electrochemical debromination reaction under set current density, reaction temperature, and material residence time conditions; and obtaining high-purity 2-chlorobenzoic acid from the outlet material through gas-liquid separation, neutralization, extraction, and recrystallization. This invention combines a continuous flow microreactor with electrochemical debromination technology, significantly enhancing mass and heat transfer, resulting in a shorter reaction time, higher conversion and yield, and the addition of a reducing agent, ease of scale-up, and intrinsic safety, demonstrating promising industrial application prospects.

The application provides a preparation method of bumetanide, taking p-chlorobenzoic acid as a starting material, performing chlorosulfonation, nitration, and ammonolysis to obtain a key intermediate of 3-(N-(tert-butyl) sulfamoyl)-4-chloro-5-nitrobenzoic acid, then performing phenoxylation, nitro reduction, n-butylation, and tert-butyl removal, and finally obtaining the bumetanide. Compared with the synthesis process of the prior art, the method has less side reactions, low cost, high yield, high safety, and is beneficial to industrial production.

The invention relates to the fields of chemistry and chemical engineering, organic synthesis and medicinal chemistry, in particular to a method for synthesizing 5-bromo-2-chlorobenzoic acid by adopting a microchannel reaction device. The method comprises the following steps: I, mixing 2-chlorobenzoic acid and sulfuric acid to obtain a reaction solution A; mixing bromine, sodium periodate, liquid organic acid and water to obtain a reaction solution B; and II, feeding the reaction liquid A and the reaction liquid B into a micro mixer of a micro-channel reaction device for mixing, then feeding the mixture into a micro reactor of the micro-channel reaction device for contact reaction, and carrying out post-treatment on contact reaction effluent to obtain the 5-bromo-2-chlorobenzoic acid. The method has the advantages of high product selectivity, high yield, high purity, convenient process, low production cost, and less by-product and three-waste pollution.

The invention provides a system for separating p-chlorobenzaldehyde and p-chlorobenzoic acid. The system comprises a crystallization tank, a circulating material tank, a desublimation tank, a temperature control device and a finished product tank. A plurality of coil pipes are arranged in the crystallization tank, the outer wall is wrapped by a jacket, and the top and the bottom are respectively provided with an upper air inlet and a lower air inlet; a plurality of devitrification plates are arranged in the desublimation tank, and a discharge port is formed in the bottom; and the temperature control device is used for regulating and controlling the temperatures of the coil pipe, the jacket and the devitrification disc. Based on the system, the p-chlorobenzoic acid is crystallized from p-chlorobenzaldehyde at a proper temperature by utilizing the solidification and sublimation characteristics of p-chlorobenzaldehyde and p-chlorobenzoic acid, then the p-chlorobenzoic acid is sublimated to the desublimation tank for desublimation by heating according to the sublimation characteristic of p-chlorobenzoic acid, and the two materials are separated in such a manner, so that the quality of p-chlorobenzoic acid is improved, and the quality of p-chlorobenzoic acid is improved. The purity of p-chlorobenzaldehyde is improved, the purity of p-chlorobenzoic acid is high after separation, no water or other solvents are added, no other hazardous waste is generated, operation is easy and convenient, and the purpose of clean production is achieved.

The invention provides a preparation method of a 2-amino-3-methyl-5-chloro-benzoic acid compound, which comprises the following synthesis route: wherein the definitions of R1 and R2 are the same as those in the specification.

The invention discloses a continuous synthesis method of 1-(2-chlorphenyl)-2-(2-tetrazolyl) ethanone, which comprises the following steps: (1) introducing a trimethylsilylated diazomethane solution and a strong alkali solution into a micro-channel reactor 1 for reaction, introducing the obtained intermediate reaction solution and a 2-chloromethyl benzoate solution into a micro-channel reactor 2 for continuous reaction, the preparation method comprises the following steps: adding 2-chlorophenyl to generate 1-(2-chlorophenyl)-2-(2-tetrazolyl-trimethylsilane) ethanone; and (2) removing a TMS group from the 1-(2-chlorphenyl)-2-(2-tetrazolyl-trimethylsilane) ethanone, and then carrying out post-treatment to obtain the 1-(2-chlorphenyl)-2-(2-tetrazolyl) ethanone. The continuous synthesis method uses a fluid process, has the advantages of small amplification effect, high production efficiency and environmental protection, improves the selectivity of 2-tetrazole, and avoids partial sensitization of intermediates.

The application belongs to the technical field of medical intermediates, and relates to a production method of a clotrimazole intermediate (2-chlorophenyl)diphenylmethanol. In the method, 2-methyltetrahydrofuran or cyclopentyl methyl ether is used as a reaction solvent, an ethyl o-chlorobenzoate solution is added dropwise into a phenyl magnesium bromide solution with a concentration of 2.5-3.5 M under the conditions of 60-80 DEG C and inert atmosphere, the reaction is continuously carried out after the dropwise addition is completed, a water solution of a quenching agent is added after the reaction to quench, then, liquid separation is carried out, and the organic phase after the liquid separation is concentrated to obtain a crude product; the crude product is refined by using a reaction solvent and petroleum ether, and (2-chlorophenyl)diphenylmethanol is obtained. The production method can efficiently and stably produce high-quality (2-chlorophenyl)diphenylmethanol, reduces production cost and safety hazards, and can be used for large-scale industrial production.

The invention discloses a method for preparing an S-isomer of montelukast sodium, which belongs to the technical field of chemical raw material medicines, and is characterized by comprising the following steps: dissolving a starting material montelukast sodium mother nucleus in an organic solvent, and carrying out configuration inversion under the action of an initiator and the catalysis of a composite catalyst to generate the S-isomer of the montelukast sodium mother nucleus; and adding 1-mercaptomethyl cyclopropyl acetic acid, reacting under the catalysis of a catalyst, filtering, cooling, growing crystal, carrying out suction filtration and drying to obtain the montelukast S-isomer. The preparation method has the beneficial effects that azodiisobutyronitrile is creatively used as an initiator, and under the catalysis of a composite catalyst tributylphosphine and m-chlorobenzoic acid, a montelukast mother nucleus is subjected to an isomerization reaction to obtain a montelukast mother nucleus S-isomer; and reacting with 1-mercaptomethyl cyclopropyl acetic acid under the catalysis of H < + >-montmorillonite to obtain the S-isomer of montelukast sodium.

The invention relates to application of m-chlorobenzoic acid in promoting growth of panax notoginseng and preventing and treating diseases. It is found that m-chlorobenzoic acid has a good pseudo-ginseng fusarium and rust rot fungus inhibiting effect, and therefore m-chlorobenzoic acid can be used for preventing and treating pseudo-ginseng root rot. In addition, the invention also finds that m-chlorobenzoic acid can promote the growth of beneficial bacteria such as trichoderma and penicillium. Therefore, after the metachlorobenzoic acid is applied to the panax notoginseng, the metachlorobenzoic acid can promote seedling storage of annual panax notoginseng, increase the dry weight of single plants of the overground part and the underground part of the panax notoginseng and promote growth of fibrous roots of the panax notoginseng.

The application discloses a synthesis process of chlorobenzoic acid, and the NiMo-Sb2O3 / TiO2-CeO2-MgO composite catalyst prepared by the method can better prepare ortho-chlorotoluene, has high selectivity and long service life, and has mild process conditions and small carbon deposition amount, so that the application has important significance for improving product quality, reducing production cost and promoting green development of the industry.

The application discloses a high-temperature-resistant and salt-resistant polymer additive for oil drilling, which is prepared by the following method: S1, carrying out nucleophilic addition on ferrocene formaldehyde and 5-amino-2-chlorobenzoic acid; S2, adding a reducing agent to the system to reduce the intermediate 1; S3, adding a catalyst to carry out aromatic nucleophilic substitution reaction under the condition of strong base and high temperature; S4, finally, carrying out esterification reaction with methacryloyl chloride; and S5, carrying out reaction on the synthetic monomer, acrylamide monomer and alkenyl monomer to obtain the polymer. The application introduces the amphiphilic macromolecular benzene ring into the main chain by reasonably controlling the process, so that the prepared additive has the advantages of less by-product, stable performance, good filtration loss reduction effect, excellent temperature resistance and salt resistance.

The utility model discloses equipment for producing o-chlorophenylacetic acid through carboxylation of o-chlorobenzyl chloride, and relates to the technical field of preparation of o-chlorophenylacetic acid. The device comprises a bottom box, a connecting ring plate is arranged over the bottom box, a heating opening is formed in the middle of the upper end face of the bottom box, a processing cylinder with the lower end located at the heating opening is arranged in the connecting ring plate, a containing ring is arranged between the connecting ring plate and the bottom box, and a plurality of notches annularly and evenly distributed along the circumferential side are formed in the circumferential side wall of the containing ring. Test tubes are arranged in the notches, and positioning rings are arranged at the upper ends of the test tubes above the placing rings in a sleeving manner. The plurality of test tubes are arranged on the peripheral side of the processing cylinder and used for containing different solvents, so that the different solvents can be conveniently put for reaction activities, and meanwhile, the upper end parts of the test tubes are limited by the positioning rings, so that the test tubes are stably placed.

The invention discloses a tail gas treatment device for o-chlorobenzonitrile production, and relates to the technical field of waste gas treatment. According to the tail gas treatment device for o-chlorobenzonitrile production, through cooperation of the middle partition plates and the filter cartridges, when waste gas enters the machine body, spraying treatment can be carried out while the waste gas is conveyed along the multiple middle partition plates, large-particle impurities in the waste gas are removed, the contact uniformity of the waste gas and spraying water is improved, and the service life of the waste gas is prolonged. And in the use process, the replacement, desorption and drying operations of the filter cartridge and the filter module can be automatically completed, so that the treatment effect of the waste gas is improved while continuous operation is ensured, and the maintenance convenience of the equipment is improved.

The present invention discloses a diphenylamine-linked chiral bis(oxazoline) ligand without C2-symmetry of formula 3 and its synthesis method and application in an asymmetric catalytic reaction, wherein C2-symmetry is lost by introducing different groups into the diphenylamine backbone to realize precise control of “electronic effect” of the ligand backbone. An anthranilic acid derivative and an orthochlorobenzoic acid derivative are used as starting materials to prepare a compound of formula 1, and then the compound of formula 1 is reacted with a chiral amino alcohol compound to prepare a β-bishydroxy amide compound of formula 2, and the compound of formula 2 is further subjected to condensation to obtain the diphenylamine-linked chiral bis(oxazoline) ligand without C2-symmetry of formula 3. The present invention also provides an application of a catalyst formed by coordination of the diphenylamine-linked chiral bis(oxazoline) ligand without C2-symmetry with copper salt, zinc salt, nickel salt, iron salt or rhodium salt, in an asymmetric catalytic reaction.

The application discloses a preparation method of a quetiapine intermediate, which comprises the following steps: taking o-aminothiophenol potassium salt as a starting material, condensing with o-chlorobenzoic acid, then performing intramolecular cyclization, and refining to obtain a target compound, i.e. dibenzo[b,f][1,4]thiazepine-11-[10H] ketone. The application optimizes process operation steps, is more convenient to operate, is safer under milder reaction conditions, has fewer side reactions, improves yield, and has a total yield of more than 85%. The obtained product is high in purity, good in quality, friendly to environment, low in pollution, and low in production cost, and is more suitable for industrial production.

The invention provides a packaged urinary catheter comprising: a urinary catheter comprising a hollow polymeric tubular body comprising a base polymer and an amphiphilic lubricious additive, the additive comprising an A-B block copolymer comprising a hydrophobic hydrocarbon A-block and a hydrophilic B-block; and an aqueous liquid medium comprising at least one species that is independently chosen from: a citric acid or citrate buffer, polyvinylpyrrolidone (PVP), polypropylene, glycerol, lactic acid, itaconic acid, succinic acid, tartaric acid, carbonic acid, ethanoic acid, boric acid, sorbic acid, mandelic acid, malic acid, propionic acid, hippuric acid, benzoic acid, pyruvic acid, formic acid, glycolic acid, m-chlorobenzoic acid, and combinations thereof, wherein at least part of the catheter is in direct contact with the aqueous liquid medium.

The invention discloses a preparation method of 1-(2-chlorphenyl)-2-(2-tetrazolyl) ethanone, which comprises the following steps: (1) under the action of an ether solvent and a strong base, enabling methyl 2-chlorobenzoate to react with trimethylsilanized diazomethane to generate 1-(2-chlorphenyl)-2-(2-tetrazolyl-trimethylsilane) ethanone; and (2) removing a TMS group from the 1-(2-chlorphenyl)-2-(2-tetrazolyl-trimethylsilane) ethanone, and then carrying out post-treatment to obtain the 1-(2-chlorphenyl)-2-(2-tetrazolyl) ethanone. According to the synthesis method, by-product isomers are reduced, the selectivity of 2-tetrazole is improved, and the total yield is further improved.

The application belongs to the technical field of chemical process, and discloses a preparation method of benzofuranone, which comprises the following steps: S1, putting o-chlorobenzoic acid, lye and quinoline copper complex into a pressurized kettle and reacting for 8-10 hours; S2, cooling the reaction liquid in the step S1 to below 25 DEG C, slowly adding concentrated hydrochloric acid into the reaction kettle under stirring, and adjusting the pH to 3-4; S3, transferring the reaction liquid in the step S2 into a dehydration kettle, putting toluene into the dehydration kettle, heating to 90-110 DEG C, and co-boiling and dehydrating, and then transferring to a cyclization kettle; S4, putting an acid catalyst into the cyclization kettle, stirring the dehydration material, and performing a cyclization reaction to generate benzofuranone. The application has the beneficial effects that the quinoline copper complex is used as a catalyst, the yield is increased by 11% compared with copper chloride, the yield of the improved method can reach 96%, the reaction temperature and the reaction pressure are reduced, the reaction conditions are improved, and the energy consumption and the safety coefficient are reduced.

The invention belongs to the technical field of medicinal chemistry, and particularly relates to an aripiprazole-4-chlorobenzoic acid-hydrate crystal form and a preparation method thereof. A basic unit of the aripiprazole crystal form is composed of one molecule of aripiprazole, one molecule of 4-chlorobenzoic acid and one molecule of water. The aripiprazole crystal form obtained by the invention has relatively high stability, and the dissolving property of the aripiprazole crystal form can meet the requirements of a sustained and controlled release preparation on the drug release characteristic, so that the stable and sustained release of the drug is realized, and the curative effect and the safety of the preparation are improved. The preparation process of the crystal form is simple, conditions are mild, process control and large-scale production are easy to realize, and the crystal form has a wide industrialization prospect.

The application provides a method for synthesizing triazine ultraviolet absorber HEB based on a copper photocatalysis strategy, and adopts the photocatalysis strategy to efficiently synthesize the ultraviolet absorber HEB at room temperature, and the method comprises the following steps: under the irradiation of blue light at room temperature, melamine and 4-chloro-N-tert-butyl benzamide are photocatalyzed by copper to obtain N-tert-butyl-4-[(4,6-diamino-1,3,5-triazin-2-yl)amino] benzamide solution; 4-chlorobenzoic acid isooctyl ester and alkali are added, and the mixture is reacted under the irradiation of blue light at room temperature; the reaction solution is filtered, water and ethyl acetate are added, and the mixture is separated; the organic phase is dried with anhydrous magnesium sulfate, and then activated carbon is added into the filtered solution to heat and reflux; then, the mixture is cooled to room temperature and filtered, the solvent is removed from the filtrate through reduced pressure distillation, and then the crude product is obtained; finally, the product HEB is obtained through recrystallization of the crude product with ethanol and water. The method has the advantages of mild reaction conditions, simple operation, low energy consumption and high product purity.

The invention belongs to the field of fine chemicals, and particularly relates to a method and a device for recycling amidation reaction byproducts. The method comprises the following steps: distilling and concentrating amidation reaction filtrate for synthesizing 2-amino-5-chloro-N, 3-dimethylbenzamide, cooling and crystallizing, filtering to obtain a mixture of a by-product and a main product, and separating the main product and the by-product, the main product is 2-amino-5-chloro-N, 3-dimethylbenzamide, the by-product is 6-chloro-3, 8-dimethyl-2, 3-dimethylbenzamide, the by-product is 2-chloro-5-chloro-N, 3-dimethylbenzamide, the by-product is 2-chloro-5-chloro-N, 3-dimethylbenzamide, the by-product is 2-chloro-5-chloro-N, 3-dimethylbenzamide, and the by-product is 2-chloro-5-chloro-N, 3-dimethylbenzamide. 2, 4 (1H, 3H)-quinazoline diketone; the method comprises the following steps: hydrolyzing a byproduct by using alkali at 100-200 DEG C to obtain 2-amino-3-methyl-5-chlorobenzoate, and neutralizing the 2-amino-3-methyl-5-chlorobenzoate to be neutral by using acid to obtain 2-amino-3-methyl-5-chlorobenzoic acid and methylamine and inorganic salt at the same time; after 2-methyl-3-amino-5-chlorobenzoic acid is separated out, alkali is added again to adjust the pH value of the solution to 9-10, methylamine is recovered through rectification, and inorganic salt is recovered through evaporation. The method is clean and environment-friendly, no three wastes are generated, and all useful substances are recycled.

This disclosure relates to 5-MeO-PiPT chloride, crystalline 5-MeO-PiPT chloride, 4-methylcarbonato-DPT chloride, crystalline 4-methylcarbonato-DPT chloride, NiPT fumarate, crystalline NiPT fumarate, NiPT chloride, crystalline NiPT chloride, MDPT iodide, crystalline MDPT iodide, 5-HT, crystalline 5-HT, 5-HT chloride butanol solvate, crystalline 5-HT chloride butanol solvate, N-cyclohexyltryptammonium fumarate, crystalline N-cyclohexyltryptammonium fumarate, 5-HO-TET iodide, crystalline 5-HO-TET iodide, TALT iodide, crystalline TALT iodide, 4-(4-chlorobenzoato)-DPT chloride, crystalline 4-(4-chlorobenzoato)-DPT chloride, and specific crystalline forms thereof, including crystalline form 1 of 5-MeO-PiPT chloride, crystalline form 1 of 4-methylcarbonato-DPT chloride, crystalline form 1 of NiPT fumarate, crystalline form 1 of NiPT chloride, crystalline form 1 of MDPT iodide, crystalline form 1 of 5-HT, crystalline form 1 of 5-HT chloride butanol solvate, crystalline form 1 of N-cyclohexyltryptammonium fumarate, crystalline form 1 of 5-HO-TET iodide, crystalline form 1 of TALT iodide, and crystalline form 1 of 4-(4-chlorobenzoato)-DPT chloride, to compositions containing the same, and to methods of treatment using them.

The application provides a preparation method of 2-chloro-6-sulfhydryl benzoic acid. Specifically provided is a preparation method of 2-chloro-6-sulfhydryl benzoic acid, which comprises the following steps: mixing a divalent palladium catalyst, a phosphine ligand, an alcohol solvent and an aromatic solvent in a protective atmosphere, adding water to pre-activate to obtain a reaction liquid; mixing the reaction liquid, a compound 2, 6-dichlorobenzoic acid, a sulfuration reagent and an inorganic base in a protective atmosphere to perform a sulfuration reaction, adding a reducing metal and an acid to react to obtain 2-chloro-6-sulfhydryl benzoic acid. The preparation method provided by the application is simple in operation, high in yield and capable of being scaled up to industrial production.

The application relates to the field of environmental engineering and discloses an iron oxide-molybdenum disulfide heterojunction catalyst as well as a preparation method and application thereof. Sodium molybdate dihydrate and cysteine are dissolved in water, ultrasonic dispersion is carried out, ball milling treatment is carried out, a sulfur-containing molybdenum-based precursor is obtained through a first hydrothermal reaction, iron salt is added to carry out a second hydrothermal reaction, and the catalyst is obtained through washing and drying. The catalyst is easy to disperse in water, has a large specific surface area, is high in iron element content and uniform in iron element distribution, can form a large number of Fe-S-Mo synergistic active centers, can efficiently activate persulfate in a pH range of 2-10, and can remove chlorobenzoic acid by about 100% in 5 minutes under the condition of an initial concentration of 10 mg / L and near-neutral pH. The catalyst has rapid and efficient degradation performance on antibiotic organic pollutants, the preparation process does not need toxic and harmful organic solvents, the catalyst has stable structure and is environment-friendly, and is suitable for engineering scale-up application.

The invention discloses a method for synthesizing 2-chlorobenzoic acid through diaphragm electrolysis debromination. According to the method, a diaphragm electrolytic cell is adopted, copper or silver is used as a cathode, a solution containing brominated 2-chlorobenzoic acid is used as a catholyte, and an alkaline aqueous solution is used as an anolyte; and enabling current to pass through the catholyte from an anode to a cathode under a normal pressure condition, performing electrolytic reduction and debromination on brominated 2-chlorobenzoic acid in the catholyte to obtain 2-chlorobenzoic acid, and recovering 2-chlorobenzoic acid after electrolysis is finished. According to the method, the 2-chlorobenzoic acid is synthesized through electrochemical debromination of the brominated 2-chlorobenzoic acid for the first time, the conversion rate of the brominated 2-chlorobenzoic acid is larger than or equal to 98%, and the yield of the 2-chlorobenzoic acid is larger than or equal to 98%. And the use of a palladium noble metal catalyst, high-explosive hydrogen and high-pressure reaction conditions are avoided.

The invention discloses a method for synthesizing 2-chlorobenzoic acid through diaphragm-free electrochemical debromination, which adopts a diaphragm-free electrolytic cell, takes copper or silver as a cathode, takes an inert conductive material as an anode, takes a solution containing brominated 2-chlorobenzoic acid as an electrolyte, and enables current to pass through the solution containing brominated 2-chlorobenzoic acid from the anode to the cathode, and the brominated 2-chlorobenzoic acid in the solution is subjected to electrolytic reduction and debromination to form 2-chlorobenzoic acid, and the 2-chlorobenzoic acid is recovered after electrolysis is finished. According to the method, the 2-chlorobenzoic acid is synthesized through electrochemical debromination of the brominated 2-chlorobenzoic acid for the first time, the conversion rate of the brominated 2-chlorobenzoic acid is larger than or equal to 98%, and the yield of the 2-chlorobenzoic acid is larger than or equal to 98%. And the use of a palladium noble metal catalyst, high-explosive hydrogen and high-pressure reaction conditions are avoided. And the use of a diaphragm electrolytic cell with complex structure, high price and difficult control is avoided.

The present application relates to the technical field of preparation of o-chlorobenzoic acid, and particularly relates to a method for preparing o-chlorobenzoic acid by electrochemical selective debromination. The method comprises the following steps: (1) using sulfuric acid aqueous solution as an anolyte and sodium hydroxide aqueous solution as a catholyte; mixing the reaction raw material chlorobenzoic acid into the catholyte and electrolyzing to debrominate; (2) adjusting the pH value of the catholyte after reaction to be acidic, separating to obtain solid and acid liquid, and performing water washing and drying on the solid to obtain white filter cake, which is o-chlorobenzoic acid; and (3) performing electrodialysis dissociation on the obtained acid liquid to obtain sodium hydroxide and recovered acid liquid respectively. The method uses chlorobenzoic acid as a raw material to prepare o-chlorobenzoic acid by electrochemical selective debromination, and through precise control of electrodes, electrolyte and electrolysis conditions, only debromination but not dechlorination of the raw material chlorobenzoic acid is realized.

The application belongs to the technical field of medicine synthesis, and particularly relates to a preparation method of a prucalopride intermediate 4-acetylamino-5-chloro-2,3-dihydrobenzofuran-7-carboxylic acid methyl ester. The method uses 4-acetylamino-3-bromo-2-(2-bromoethoxy)-5-chlorobenzoic acid methyl ester (SM-1) as a starting material, and the target product is prepared through dehalogen coupling, which can effectively solve the problem of low operation safety of sodium metal dehalogen coupling, and can also solve the problem of long production time of the zinc powder coupling technical scheme, and is suitable for industrialized scale production. The obtained product has high yield and purity.