68 results about "Butyl bromide" patented technology

The invention relates to the technical field of chemical synthesis, and provides a synthesis method of 2, 4-difluoronitrobenzene, which comprises the following steps: under the action of a catalyst, carrying out fluorination reaction on 2, 4-dichloronitrobenzene and a fluorinating agent to obtain 2, 4-difluoronitrobenzene; the catalyst comprises tetrabutylammonium bromide and tetrabutylammonium chloride, and the mass ratio of the tetrabutylammonium bromide to the tetrabutylammonium chloride is (1: 5)-(5: 1). According to the technical scheme, the problems of low yield and low purity during synthesis of 2, 4-difluoronitrobenzene in related technologies are solved.

The invention discloses a method for preparing spermidine. The method comprises the following steps: dissolving oxalyl chloride and a base in a first solvent, slowly adding 4-bromo-1-butylamine hydrobromic acid, and reacting to obtain 2-((4-bromobutyl)amino)-2-oxoacetyl chloride; adding a base to the reaction solvent of the obtained 2-((4-bromobutyl)amino)-2-oxoacetyl chloride, and slowly adding 3-bromo-1-propylamine hydrobromic acid to obtain N 1 ‑(4‑Bromobutyl)‑N 2 ‑(3‑bromopropyl)oxalamide; 1 ‑(4‑Bromobutyl)‑N 2 ‑(3‑bromopropyl)oxalamide, benzylamine and a base are added to a second solvent to react to obtain 8‑benzyl‑1,4,8‑triazacyclododecane‑2,3‑dione; 8‑benzyl‑1,4,8‑triazacyclododecane‑2,3‑dione is added to an acid for hydrolysis to obtain N 1 ‑(3‑Aminopropyl)‑N 1 Benzylbutane-1,4-diamine; N 1 ‑(3‑Aminopropyl)‑N 1 Benzylbutane-1,4-diamine is added to Raney nickel / methanol, and hydrogen is passed through the reaction to obtain crude spermidine, which is then distilled to obtain pure spermidine. The preparation method of the present invention is easy to operate and safe, easy to industrial-scale production, and has a high conversion rate of spermidine and high product purity.

The invention discloses an imidazole polymer electrolyte membrane in an energy storage lithium battery, and a preparation method and application thereof, and belongs to the field of polymer electrolyte. The method comprises the following steps: reacting 1-ethylimidazole with n-butyl bromide to prepare brominated 1-ethyl-3-butylimidazole; the preparation method comprises the following steps: preparing 1-ethyl-3-butylimidazole bis (fluoromethane sulfonyl) imide salt from brominated 1-ethyl-3-butylimidazole and lithium bis (fluoromethane sulfonyl) imide; the preparation method comprises the following steps: uniformly mixing 1-ethyl-3-butylimidazolium bis (fluoromethane) sulfonimide salt, polyethylene glycol methyl ether methacrylate, acrylonitrile, lithium bis (trifluoromethane) sulfonimide, divinylbenzene and benzoin diethyl ether, coating and curing to obtain the imidazolium ionic liquid polymer electrolyte membrane. According to the imidazolium ionic liquid polymer electrolyte membrane, integration of triple functions of rigid framework-flexible transmission-interface stability is realized, and the electrical property and the mechanical property of the membrane are remarkably improved.

The application discloses a synthesis method of afugan, which comprises the following steps: 1-[3-chloro-5-(trifluoromethyl)phenyl]-2,2,2-trifluoroacetone and 4-acetylnaphthalene carboxylic acid are added into a solvent, a base is added, DMAP is added after complete reaction at 50-80 DEG C, acetic anhydride is added dropwise, tetrabutylammonium bromide is added after complete reaction, and an aqueous solution of sodium hydroxide and hydroxylamine hydrochloride is added, and reaction is carried out at 0-5 DEG C, so that an intermediate is obtained; the intermediate is reacted with acyl chloride under the action of DMF and dichloromethane, so that 4-(5-(3-chloro-5-(trifluoromethyl)phenyl)-5-(trifluoromethyl)-4,5-dihydroisoxazole-3-yl)-1-naphthalene carboxylic chloride is prepared; 2-amino-N-(2,2,2-trifluoroethyl)acetamide hydrochloride and a dichloromethane solution of a base are added dropwise, and reaction is carried out at 0-5 DEG C, so that afugan is obtained. The method has a short route, high yield and suitability for large-scale industrial production.

The present invention relates to the technical field of chemical synthesis, and provides a method for synthesizing 2,4-difluoronitrobenzene, which includes the following steps: under the action of a catalyst, 2,4-dichloronitrobenzene and a fluorinating agent are subjected to a fluorination reaction to obtain 2,4-difluoronitrobenzene; the catalyst includes tetrabutylammonium bromide and tetrabutylammonium chloride, and the mass ratio of tetrabutylammonium bromide to tetrabutylammonium chloride is 1:5 to 5:1. Through the above technical solution, the problems of low yield and low purity in the synthesis of 2,4-difluoronitrobenzene in the related art are solved.

The invention discloses a method for synthesizing dihydrocapsaicin, and the method comprises the following steps: synthesizing a first intermediate 1-isobutylcyclohexene, a second intermediate 8-methyl-6-oxonanoic acid, a third intermediate 8-methylnonanoic acid and a target product dihydrocapsaicin. The method uses cyclohexanone, isobutylmagnesium bromide and vanillin ammonium hydrochloride as raw materials, and obtains the product dihydrocapsaicin by stepwise reaction. Each reaction step adopts a conventional chemical reaction, and the reaction conditions are mild. The feasibility of the synthesis process is high, the safety and environmental protection are strong, and the product has a high yield and good purity, and is suitable for industrial production.

The method comprises the following steps: adding 1-[3-chloro-5-(trifluoromethyl) phenyl]-2, 2, 2-trifluoroethanone and 4-acetyl naphthoic acid into a solvent, adding alkali, completely reacting at 50-80 DEG C, then adding DMAP, dropwise adding acetic anhydride, completely reacting, then adding tetrabutylammonium bromide, and reacting at 50-80 DEG C for 2-3 hours to obtain the arfamarana. Adding an aqueous solution of sodium hydroxide and hydroxylamine hydrochloride, and reacting at 0-5 DEG C to obtain an intermediate; reacting the intermediate with acyl chloride under the action of DMF (Dimethyl Formamide) and dichloromethane to obtain 4-(5-(3-chloro-5-(trifluoromethyl) phenyl)-5-(trifluoromethyl)-4, 5-dihydroisoxazole-3-yl)-1-naphthoyl chloride; the preparation method comprises the following steps of: adding a catalyst into an organic solvent, dropwise adding into a dichloromethane solution of 2-amino-N-(2, 2, 2-trifluoroethyl) acetamide hydrochloride and alkali, and reacting at the temperature of between 0 and 5 DEG C, so as to obtain the arfola sodium. The method is short in route, high in yield and suitable for large-scale industrial production.

The invention relates to the technical field of rubber linings, and particularly discloses a special brominated butyl rubber lining material for a nuclear power plant and a preparation process. The material is prepared from the following components in parts by weight: 100.0 parts of butyl bromide, 20.0 parts of high-abrasion-resistance carbon black, 30.0 parts of semi-reinforcing carbon black, 8.0 parts of naphthenic oil, 2.0 parts of zinc oxide, 0.1 part of magnesium oxide, 1.0 part of stearic acid, 1.0 part of an accelerant and 1.0 part of vulcanized resin. The material has the advantages of complete saturation of a main chain, excellent aging resistance, high bonding strength and the like, greatly improves the aging resistance compared with the existing chloroprene rubber and hard natural rubber anticorrosive linings of nuclear power plants, can better meet the use requirements of the rubber linings of the nuclear power plants, and prolongs the service life of the rubber linings.

The invention relates to the technical field of preparation of tert-butyl carbamate, in particular to a preparation method of (R)-(1-([1, 1 '-biphenyl]-4-yl)-3-oxopropane-2-yl) tert-butyl carbamate. Comprising the following steps: S1, taking a four-mouth bottle, adding 1780 g of dichloromethane, 165 g of (R)-tert-butyl (1-([1, 1 '-biphenyl]-4-yl)-3-hydroxypropane-2-yl) carbamate, 1.6 g of TEMPO and 2 g of tetrabutylammonium bromide into the four-mouth bottle, and stirring the four-mouth bottle, the dichloromethane, the (R)-tert-butyl (1-([1, 1'-biphenyl]-4-yl)-3-hydroxypropane-2-yl) carbamate, the TEMPO and the tetrabutylammonium bromide; s2, 33.5 g of a sodium bromide solution and 146 g of clear water of a phosphoric acid mixed salt solution are added into the four-opening bottle after stirring in the step S1, and liquid in the four-opening bottle is cooled to a specified temperature; s3, sodium hypochlorite with the available chlorine content being 9-10% is dropwise added into the four-opening bottle cooled in the S2; and S4, after dripping in the step S3 is completed, preserving the heat of the liquid in the four-mouth bottle, and adding 385 g of a sodium thiosulfate solution into the bottle for quenching reaction. And S5, sampling and detecting. The pH value buffering agent of a phosphate system, namely a sodium dihydrogen phosphate-disodium hydrogen phosphate composite salt system, is used, and the yield is 90-96%.

The invention belongs to the technical field of organic synthesis, and relates to a preparation process of o-nitrobenzaldehyde. According to the method, o-nitrotoluene is taken as a starting raw material, hydrogen peroxide is taken as an oxidizing agent, water is taken as a solvent, under the protection of nitrogen, under the action of a phase transfer catalyst tetrabutylammonium bromide and a catalyst manganese dioxide, o-nitrotoluene is subjected to oxidation reaction to obtain o-nitrobenzaldehyde, water is taken as a solvent, bromine and wastewater containing bromine, chromium and the like are not used, the operation is simple and convenient, and the method is suitable for industrial production. The process temperature is mild and easy to control, and the obtained product is stable in quality, low in impurity content and remarkable in environmental benefit.

The invention belongs to the technical field of wet metallurgy extraction agents, and particularly relates to an amide extraction agent and a preparation method and application thereof. The preparation method of the amide extracting agent comprises the following steps: (1) putting n-butyl bromide and sec-butylamine into a reactor, reacting in a homogeneous reactor for 6-10 hours, washing with a saturated sodium bicarbonate solution after the reaction is finished, then separating liquid, and carrying out rotary evaporation on an organic phase to obtain N-butyl sec-butylamine; (2) dissolving N-butyl sec-butylamine in an organic solvent, dropwise adding diglycyl chloride into the solvent at-20 to 0 DEG C, reacting at room temperature for 1-5 hours after dropwise adding, filtering to remove precipitate, washing an organic phase with hydrochloric acid and secondary water in sequence, removing water with anhydrous sodium sulfate, performing rotary evaporation on the organic phase, and performing vacuum drying on a product to obtain the N, N '-di-n-butyl-N, N'-diglycyl chloride. The catalyst is N, N '-di-sec-butyl-3-oxoglutaramide.

This invention provides a method for preparing tetrabutylphosphine acetate and simultaneously producing sodium bromide, belonging to the field of organophosphine salt preparation and electrodialysis separation technology. The method provided by this invention uses sodium acetate and tetrabutylphosphine bromide as raw materials, and prepares tetrabutylphosphine acetate and simultaneously produces sodium bromide via displacement electrodialysis. This achieves efficient ion exchange between tetrabutylphosphine bromide and sodium acetate, and simultaneous recovery of sodium bromide. The preparation method is simple, avoids the use of large amounts of chemical reagents, and reduces environmental pollution.

The invention relates to the field of synthesis and preparation of hydroquinone, in particular to a synthesis method of high-purity hydroquinone. In order to solve the problem that in the existing process of preparing hydroquinone through a phenol hydrogen peroxide oxidation method, the selectivity of hydroquinone (HQ) is improved, and by-products with similar microstructures are generated synergistically and are difficult to remove, a composite catalysis synergistic inhibition system of phosphotungstic acid, tetrabutylammonium bromide and imidazole is adopted; through the synergistic effect of the main catalyst, the selectivity regulator and the byproduct inhibitor, HQ selectivity improvement and synchronous inhibition of trace byproducts are achieved under the optimized reaction condition, the total content of the trace byproducts is smaller than or equal to 45 ppm, the purity of the final hydroquinone product is larger than or equal to 99.995%, and the high-end application requirements of electronic-grade and photoresist raw materials are met. The technology is compatible with existing industrial equipment, operation is easy, and industrial production is met.

The invention provides an application of tetra-n-butylammonium bromide as a catalyst to catalyze reaction of methoxy aromatic hydrocarbon and acyl bromide, compared with the prior art, methoxy aromatic hydrocarbon and acyl bromide are used as raw materials, tetra-n-butylammonium bromide is used as the catalyst, esterification reaction is carried out under catalysis, and an esterification product is obtained. Wherein tetra-n-butylammonium bromide (TBAB) is dissociated into tetrabutylammonium cations (TBA < + >) and bromide ions (Br <->) in the reaction, and the tetrabutylammonium cations interact with oxygen atoms in the methoxy aromatic hydrocarbon, so that the oxygen atoms are polarized, and an intermediate I is obtained; taking bromine ions (Br <->) as a nucleophilic reagent, attacking sp3C-O bonds to form an intermediate II, carrying out nucleophilic substitution reaction on the intermediate II and acyl bromide to generate an esterification product, and regenerating tetra-n-butylammonium bromide; the tetra-n-butylammonium bromide can be circularly used for catalytic reaction. The raw materials used in the method are wide in source and low in cost, and the method has the advantages of atom economy and high yield and has a wide application prospect.

The invention relates to a multi-element thermodynamic accelerant for sealing carbon dioxide by hydrate and application of the multi-element thermodynamic accelerant, the multi-element thermodynamic accelerant comprises sodium glycinate (NaGly), octyl glucoside (OGP) serving as a surfactant, tetrabutylammonium bromide (TBAB) serving as a thermodynamic accelerant and tetrahydrofuran (THF) serving as an organic solvent, and after the sodium glycinate (NaGly), the octyl glucoside (OGP) serving as a surfactant, the tetrabutylammonium bromide (TBAB) and the tetrahydrofuran (THF) are mixed with water, the mass percent concentration of the NaGly is 0.001-1wt%, the mass percent concentration of the OGP is 0.001-1wt%, the mass percent concentration of the TBAB is 5-50wt%, and the mass percent concentration of the THF is 4-40wt%. NaGly can improve the stability of the hydrate, OGP can improve the generation rate of the hydrate, TBAB can improve the formation speed and efficiency of the hydrate, THF can promote rapid generation of the hydrate, the generation speed of the hydrate is remarkably increased through cooperation of NaGly, OGP, TBAB and THF, the generation time is shortened, and the storage efficiency of carbon dioxide is effectively improved.

The present invention relates to the technical field of p-chlorophenylglycine preparation, and proposes a method for preparing p-chlorophenylglycine, comprising the following steps: S1, mixing ammonia water and sodium hydroxide solution, and introducing ammonia gas until saturated to obtain a mixed solution I; S2, adding p-chlorobenzaldehyde and a phase transfer catalyst to chloroform to obtain a mixed solution II; S3, adding the mixed solution II to the mixed solution I, adding ammonium bicarbonate, and stirring for reaction to obtain p-chlorophenylglycine; the phase transfer catalyst comprises tetrabutylammonium bromide and polyethylene glycol 400; the molar ratio of tetrabutylammonium bromide to polyethylene glycol 400 is 7:1-7. The above technical solution solves the problem of low p-chlorophenylglycine yield in the related art.

The invention provides a method for preparing 2, 4, 6-tri (4 '-butoxy-2'-hydroxyphenyl)-triazine, which comprises the following steps: in the presence of an alkaline reagent, dissolving m-bromophenol and n-butyl bromide in a first solvent to carry out nucleophilic substitution reaction, and after the reaction is finished, carrying out post-treatment to obtain 1-bromo-3-butoxybenzene; magnesium chips and an initiator are dissolved in a second solvent for a reaction, then the 1-bromo-3-butoxybenzene is dropwise added for a Grignard reaction, and a 3-butoxybenzene Grignard reagent is obtained; dropwise adding boric acid ester into the 3-butoxybenzene Grignard reagent for reaction, and then adding an oxidizing agent for oxidation reaction to obtain 3-butoxyphenol; 3-butoxyphenol and cyanuric chloride are dissolved in a third solvent for a reaction, lewis acid is added for a Friedel-Crafts reaction, after the reaction is finished, aftertreatment is conducted, and the 2, 4, 6-tri (4 '-butoxy-2'-hydroxyphenyl)-triazine is obtained.The preparation method is lower in cost, higher in yield, high in product quality and easy to control.

The invention relates to the technical field of layered composite fabrics, in particular to a layered composite fabric based on a waterproof and weather-resistant coating, a preparation method and application. The layered composite fabric comprises an outer-layer fabric and an inner-layer fabric, the inner-layer fabric is a bamboo cotton fabric, the outer-layer fabric is a nylon fabric with a waterproof and weather-resistant coating, and the nylon fabric with the waterproof and weather-resistant coating is prepared by dipping a bio-based nylon fabric in a composite finishing agent and curing the bio-based nylon fabric. The composite finishing agent is prepared by the following steps: carrying out a reaction on diisocyanate, polyether polyol, bio-based polyester polyol and hydroxyl-terminated polydimethylsiloxane in N, N-dimethylacetamide, so as to prepare a polyurethane prepolymer solution; n-octadecyl diethanolamine is added for a chain extension reaction; n-butyl bromide is added, and quaternization reaction is carried out; and finally, adding the composite weather-resistant auxiliary agent, and stirring to obtain the composite finishing agent.

The application belongs to the field of organic synthesis, and particularly relates to a method for synergistically synthesizing 1,1-diaryl-2-alkyl compounds by using nickel and light. The method comprises the following steps: using styrene derivatives, p-bromoacetophenone and tert-butyl bromide as raw materials, and mixing a metal nickel catalyst (nickel bis(acetylacetone)), a photocatalyst (1,2,3,5-tetrakis(carbazole-9-yl)-4,6-dicyano benzene), a nitrogen ligand ((4S,4'S)-1,1'-bis(3-tert-butylphenyl)-4,4',5,5'-tetrahydro-4,4'-bis[(1S)-1-methylpropyl]-2,2'-bis-4H-imidazole), a Bronsted base (N,N-dicyclohexylmethylamine), a reducing agent (1,4-dihydropyridine derivatives) and an organic solvent (glycol dimethyl ether, isopropyl ether) to generate a three-component cross-coupling reaction and synthesize 1,1-diaryl-2-alkyl compounds with one chiral center. The three-component cross-coupling reaction is realized by using nickel and light, so that the use of a metal reducing agent is avoided, and the preparation raw materials are not needed. The method has the advantages of high reaction yield, high enantiomeric selectivity, fast reaction speed, easy-to-obtain raw materials and simple process.

The invention discloses a method for synthesizing R-2-(4-hydroxyphenoxy) propionic acid by submerged culture of beauveria bassiana, and provides a submerged culture method of R-2-(4-hydroxyphenoxy) propionic acid, which comprises the following steps: adding soybean oil and a phase transfer catalyst; the phase transfer catalyst is prepared from one or more of cyclodextrin, tetrabutylammonium bromide, 1-butyl-3-methylimidazolium hexafluorophosphate and polyethylene glycol 1000. By adopting a supplementary material synergistic method, the yield of the R-2-(4-hydroxyphenoxy) propionic acid produced by using the beauveria bassiana ZJB23323 as a production strain through deep culture is remarkably improved.

The present application provides a method for extracting a phenol compound and a pyridine compound from naphthalene oil stepwise by using a deep eutectic solvent (DES). The method comprises: step 1, mixing a naphthalene oil with an alkane and a DES and performing liquid separation on the mixture to obtain a deep eutectic extraction phase and a solvent raffinate phase; step 2, mixing the deep eutectic extraction phase with a first back-extraction agent and filtering the mixture to obtain a first back-extraction phase and a recyclable DES; step 3, distilling the first back-extraction phase to obtain a heteroatom mixture, mixing the heteroatom mixture with a hydrogen-acceptor-type deep eutectic extraction agent and an alkane, and performing liquid separation on the mixture to obtain a deep eutectic phenol compound extraction phase and a pyridine compound and alkane raffinate phase; and step 4, mixing the phenol compound extraction phase with a second back-extraction agent and filtering the mixture to obtain a phenol-containing second back-extraction solution and a hydrogen-acceptor-type extraction agent. A phenol product is recovered from a second back-extraction agent solution by distillation. The DES is tetraethylammonium chloride, tetrabutylammonium chloride, tetrabutylammonium bromide or tetrabutylphosphonium bromide, and glycolic acid, oxalic acid, citric acid, or p-toluenesulfonic acid.

The present invention belongs to the field of biochemistry and relates to a method for preparing a biochemical product having H2S and 1 O2 synergistically drives the BODIPY flavonoid nanoreagent of CO release ability and its preparation method and application. It is wrapped in the hydrophobic inner cavity of the micelle formed by mPEG DSPE2000, and the outer layer of the micelle is a silicon shell formed by N trimethoxysilylpropyl N, N, N tri-n-butylammonium bromide, which significantly improves the water solubility of the molecule. The core-shell structure of the formed nanomolecule is relatively stable, which can significantly improve the stability of the molecule in water. The iodinated BODIPY flavonoid compound of the present invention has very good photodynamic effect and CO release ability, has a very high singlet oxygen production efficiency under 660nm light irradiation, and has excellent stability. It has and its considerable application prospects in photodynamic and gas therapy in the fields of biochemistry and medicine. The phototherapy reagent synthesis method provided by the present invention is simple and relatively low in cost.

The invention relates to a composite hydrate inhibitor for carbon sequestration, which comprises polyvinylpyrrolidone (PVP) serving as a kinetic inhibitor, tetrabutylammonium bromide (TBAB) serving as a thermodynamic accelerant and tetrahydrofuran (THF) serving as an organic solvent, and after the polyvinylpyrrolidone (PVP), the tetrabutylammonium bromide (TBAB) and the tetrahydrofuran (THF) are mixed with water, the concentrations of the PVP, the TBAB and the THF are respectively as follows: 0.001-1wt% of the PVP, 0-50wt% of the TBAB and 0-50wt% of the THF. The PVP, the TBAB and the THF are combined according to the proportion to form the composite hydrate inhibitor, and through the synergistic effect of the PVP, the TBAB and the THF, the generation speed of hydrates is increased, the carbon dioxide storage efficiency is improved, meanwhile, the aggregation degree of the hydrates can be reduced, and the blocking probability is reduced.

The application discloses a method for degrading tetrabutylphosphonium bromide by using tetrahymena. The method is for degrading tetrabutylphosphonium bromide by using tetrahymena in a starvation medium under aerobic conditions. The application first proposes the purpose of eliminating tetrabutylphosphonium bromide through biological degradation of tetrahymena pyriformis. The application provides a new idea for degradation of tetrabutylphosphonium bromide, and has potential to be further optimized and popularized. The method has the advantages of green environmental protection and no energy consumption.

The present invention discloses an imidazole polymer electrolyte membrane for energy storage lithium batteries, a preparation method, and applications thereof, belonging to the field of polymer electrolytes. The method comprises reacting 1-ethylimidazole with n-butyl bromide to produce 1-ethyl-3-butylimidazole bromide; reacting 1-ethyl-3-butylimidazole bromide with lithium bis(trifluoromethanesulfonyl)imide to produce 1-ethyl-3-butylimidazole bis(fluoromethanesulfonyl)imide salt; and uniformly mixing 1-ethyl-3-butylimidazole bis(fluoromethanesulfonyl)imide salt, polyethylene glycol methyl ether methacrylate, acrylonitrile, lithium bis(trifluoromethanesulfonyl)imide, divinylbenzene, and benzoin ethyl ether, coating the mixture, and curing the mixture to produce an imidazole ionic liquid polymer electrolyte membrane. The imidazole ionic liquid polymer electrolyte membrane achieves a triple functional integration of "rigid skeleton, flexible transmission, and interface stability," significantly improving its electrical and mechanical properties.

The invention relates to an ionic composite hydrate accelerant for carbon sequestration, which comprises amino acid salt: sodium glycinate NaGly, a surfactant: octyl glucoside OGP, a thermodynamic accelerant: tetrabutylammonium bromide TBAB and a dynamic accelerant: lauryl sodium sulfate SDS, and after the four components are mixed with water, the mass percent concentration of NaGly (0.001-1wt%) + OGP (0.001-1wt%) + SDS (0.001-1wt%) + TBAB (5-50wt%) is obtained. NaGly, OGP, TBAB and SDS are combined according to the proportion to form the ionic composite hydrate accelerant, the generation speed of hydrate is remarkably increased through cooperation of the four components, the generation time is shortened, and the sealing efficiency of carbon dioxide is effectively improved.

The invention relates to the technical field of medicine synthesis, in particular to a preparation method of high-purity levetiracetam. According to the method, (S)-2-aminobutanamide hydrochloride and 4-chlorobutyryl chloride are used as raw materials, and high-purity levetiracetam is prepared through an acylation reaction, a cyclization reaction and a specific crystallization process. The preparation method of the levetiracetam is simple and convenient, simple to operate and low in cost, and also effectively avoids the risk of introducing a toxic impurity tetrabutylammonium bromide. By utilizing the method disclosed by the invention, the problems of low purity and yield of a product and high cost caused by the fact that tetrabutylammonium bromide is required to be added in a method for synthesizing levetiracetam in the prior art are effectively solved.

The invention discloses a ferric oxide / phosphomolybdic acid composite material and a preparation method and use thereof. Firstly, Fe2O3 nanoparticles and Dawson type phosphomolybdic acid P2Mo are prepared. 18 ; Tetrabutylammonium bromide was used as a surfactant to convert Dawson type P2Mo 18 The ferric oxide / phosphomolybdic acid composite material is prepared by compounding with Fe2O3 nanoparticles, and the preparation process is simple. The prepared ferric oxide / phosphomolybdic acid composite material can photocatalytically degrade methylene blue and potassium dichromate, and the degradation effect is good. The final degradation rate of methylene blue can reach 99%, and the degradation rate of potassium dichromate solution after adding methanol can reach 96%.

The present invention relates to a method for synthesizing tetracaine, comprising the steps of: using N-Boc-4-aminobenzoic acid (A) as a raw material, and reacting with n-butyl bromide to obtain N-Boc-N-butyl-4-aminobenzoic acid butyl ester (B); removing Boc from N-Boc-N-butyl-4-aminobenzoic acid butyl ester (B) under weak acid to obtain N-butyl-4-aminobenzoic acid butyl ester (C); and reacting N-butyl-4-aminobenzoic acid butyl ester (C) with N,N-dimethylethanolamine to obtain tetracaine (I). This method effectively reduces the risk of generating N-disubstituted butyl impurities, does not require palladium-carbon hydrogenation, and the purity and yield of the prepared tetracaine are both high, the product purity is greater than 99.8%, and the single impurity is less than 0.05%, which meets the requirements of medicinal raw materials.

The invention discloses a preparation method of fluoroethylene carbonate, and relates to the technical field of chemical production, and the preparation method comprises the following steps: treating chloroethylene carbonate by a 3A molecular sieve adsorption tower, and controlling free acid to be less than or equal to 30ppm; the method comprises the following steps: mixing crown ether, tetrabutylammonium bromide, tetrabutylammonium bromide and mesoporous silica to prepare a composite catalyst; 2, continuously feeding inert gas into the reaction kettle, after air replacement in the reaction kettle is completed, feeding the pretreated chloroethylene carbonate, the compound chelating agent, the solvent and the composite catalyst in the step 1 into the reaction kettle, stirring and mixing, and then adding fluoride salt in 10 times to prepare a fluoroethylene carbonate crude product; and leaching, filtering and rectifying the fluoroethylene carbonate crude product to obtain the finished fluoroethylene carbonate. Therefore, by compounding the chelating agent, redundant metal ions in the reaction are effectively reduced, and the purity of the final product is ensured.