147 results about "Nitrobenzene" patented technology

This invention discloses a method for preparing and analyzing trans-4-aminocyclohexylacetic acid. The preparation method is as follows: 4-nitrophenylacetic acid undergoes catalytic hydrogenation in a solvent, followed by filtration. The filtrate is then treated with acid to obtain a 4-aminophenylacetic acid salt solution. The collected catalyst is activated. The 4-aminophenylacetic acid salt solution is mixed with isopropanol, barium hydroxide, tetrabutylammonium bromide, 18-crown ether-6, and dibutyl phthalate. The activated catalyst is then added to initiate a catalytic hydrogenation reaction. After the reaction, the reaction solution is cooled and filtered. The resulting solid is mixed with a preheated dilute sulfuric acid solution and stirred to form a slurry. The mixture is then filtered, and the filtrate is neutralized and filtered again. The collected filtrate is concentrated and crystallized. The crystallized precipitate is washed and dried to obtain trans-4-aminocyclohexylacetic acid. The method provided by this invention has high reaction efficiency, mild conditions, and is suitable for industrial production. It yields high product purity and reliability. Furthermore, the analytical method provided by this invention is accurate and reliable.

This invention discloses a continuous synthesis apparatus and process for nitrobenzene. The synthesis apparatus includes a mixed acid preparation system, a continuous benzene nitration system, an organic phase continuous stratification system, and a continuous water washing-alkali washing-water washing system. The process includes: concentrated sulfuric acid and concentrated nitric acid are pumped into the mixing module of the mixed acid preparation system to obtain a mixed acid solution; benzene and the mixed acid solution are pumped into the microchannel reactor of the continuous benzene nitration system; the nitrated material is cooled and then pumped into the continuous organic phase stratification system; the resulting intermediate organic phase nitrate enters the next processing unit; the organic phase nitrate and water enter the continuous water washing-alkali washing-water washing system for washing to obtain the final product, nitrobenzene. The synthesis apparatus and process of this invention achieve continuous production of nitrobenzene throughout the entire process, realizing continuous and automated operation from raw material benzene to the final product, nitrobenzene.

The application provides a preparation method of an indobufen key intermediate. The method uses 2-(4-nitrophenyl) butyric acid and phthalic anhydride as raw materials, and obtains the target compound (I) through a one-pot method. The method has the advantages of simple operation, mild conditions, high reaction yield, reduced cost through mother liquor recycling and reuse, significantly reduced "three wastes" and environmental protection, and is suitable for large-scale industrial production.

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

The application provides a regeneration method of halogenated nitrobenzene continuous hydrogenation catalyst, and relates to the technical field of fixed bed halogenated nitrobenzene hydrogenation. The regeneration method mainly comprises the following steps: using alcohol, alkali, petroleum ether and ethyl acetate to preliminarily clean the bed layer, removing azo compounds and other pollutants on the surface of the catalyst by using the special properties of ionic liquids, and then completing the regeneration of the catalyst through the steps of pickling, precious metal solution treatment and drying. The application overcomes the defects of the prior art, has the advantages of simple operation, mild conditions and low cost, realizes the in-situ removal of surface impurities such as reaction intermediates and azo compounds on the catalyst surface without damaging the structure of the catalyst and disassembling the catalyst, further supplements the lost metal active components, and can effectively restore the catalyst activity.

The application discloses a copper oxide nanowire loaded silver monatomic catalyst, a preparation method and application thereof, and comprises a substrate, CuO nanowires and metal Ag monatomic atoms loaded on a CuO nanowire electrode layer; the substrate is a commercial copper foam, and the substrate is used for providing a copper source and preparing an array material of the metal Ag monatomic atoms on the CuO nanowires. The application adopts the above-mentioned copper oxide nanowire loaded silver monatomic catalyst, the preparation method and the application thereof, through silver monatomic atom modification, copper-silver metal interaction jointly regulates an intermediate product in an adsorption electrocatalytic reduction process, excellent electrocatalytic nitrophenol reduction performance is obtained, and the application is suitable for environmental pollution treatment and pharmaceutical synthesis development fields.

This invention discloses a method for preparing the DPP1 inhibitor bresocarte, belonging to the field of pharmaceutical synthesis. Specifically, the method includes the following steps: N-tert-butoxycarbonyl-L-4-bromophenylalanine reacts with methanesulfonyl chloride or 4-nitrobenzenesulfonyl chloride in the presence of a base, followed by amination substitution to obtain intermediate 1; then, it undergoes dehydration in the presence of trifluoroacetic anhydride to obtain intermediate 2; next, it undergoes a coupling reaction with pinacol diboronate to obtain intermediate 3; then, it undergoes a coupling reaction with bromide compound 4 to obtain intermediate 5; then, it undergoes cyclization with di-tert-butyl dicarbonate in the presence of sodium methoxide to obtain intermediate 6; then, it undergoes deprotection in the presence of hydrogen chloride to obtain intermediate 7; next, it undergoes condensation with compound 8 to obtain intermediate 9; finally, it undergoes deprotection in the presence of hydrogen chloride to obtain the inhibitor bresocarte. This method provides a new synthetic approach, with low overall cost, simple operation, high yield, and suitability for industrial production.

This invention discloses a complete process for preparing nitrobenzene using a microchannel reactor, belonging to the field of nitrobenzene synthesis. The complete process includes mixed acid, microchannel nitration reaction, intermediate product cooling and stratification followed by water and alkali washing, crude product distillation, waste acid recovery, and wastewater treatment. Compared with existing nitrobenzene synthesis technologies, this invention has high mass transfer efficiency, significantly shortens the nitration reaction time, greatly improves production efficiency, enhances reaction safety, and simultaneously achieves waste acid recovery and wastewater treatment, ensuring safe, environmentally friendly, and stable production.

The present invention aims to provide an additive for agricultural chemicals that exhibits excellent spreading properties. [Solution] The present invention provides an additive for pesticides and an additive for pesticides for paddy fields or hydroponics, which contains a lignin derivative having a weight-average molecular weight of 5,000 to 43,000, preferably 5,000 to 36,000, an organic sulfur content of 1.5 to 7.0% by mass, preferably 1.5 to 5.5% by mass, a water solubility of 10 to 100% by mass, an extractant content and a methoxy group content of 0.01 to 2.5% by mass and 3 to 17% by mass, respectively, with a mass ratio of extractant content to methoxy group content of 0.001 to 0.25, and having a functional group represented by formula (1):-SO3M. The lignin derivative preferably satisfies the following conditions: a total decomposition product yield by alkaline nitrobenzene oxidation of 14% or less, and a polydispersity of at least one selected from 1.5 to 4.7.

The application provides a kind of plane chiral boronic acid compound based on cycloaralkane skeleton and its synthesis method and application, the plane chiral compound has the structure shown in formula I;R 1 It is selected from one of C1-C8 alkyl, C1-C8 alkoxy, C1-C20 aryloxy.R 2 It is selected from one of hydrogen, fluorine, methyl, ethyl, methoxy, ester group, nitro group, phenyl, benzyl, tert-butyl, isopropyl.The application can effectively synthesize plane chiral boronic acid catalyst based on cycloaralkane skeleton, and the plane chiral boronic acid catalyst based on cycloaralkane skeleton can realize diol desymmetrization reaction.

This invention relates to a method for the liquid-phase adsorption separation and purification of 2,3-dichloronitrobenzene and 3,4-dichloronitrobenzene, belonging to the field of chemical separation. This method for the simultaneous separation and purification of 2,3-dichloronitrobenzene and 3,4-dichloronitrobenzene involves preparing small spherical molecular sieve adsorbents from USY molecular sieves, silicon coupling agent-modified illite, and biomass polysaccharides, which are then loaded into a countercurrent simulated moving bed for separation and purification. This method can simultaneously obtain 2,3-dichloronitrobenzene and 3,4-dichloronitrobenzene with a purity ≥99%. The separation and purification method adopted in this invention is not only energy-efficient and highly effective, but also enables continuous production of two high-purity dichloronitrobenzenes, possessing significant industrial application value.

This invention discloses a novel method for preparing a clean fuel additive, relating to the field of clean fuel additive technology. Its components include: a main cleaning agent: Mannich base; a dispersant: polyetheramine; a surfactant: highly active polyisobutylene; an antioxidant: N,N-di-sec-butyl-p-phenylenediamine; an octane booster: dimethyl carbonate; a solvent: 120# solvent oil; a combustion improver: C9-C11 mixed olefins; a stabilizer: trimethylolpropane; an ignition promoter: nitrobenzene; and auxiliary additives: n-dodecane, sodium polystyrene sulfonate, and eugenol methyl ether. This invention achieves a significant synergistic effect among the core components such as Mannich base, polyetheramine, polyisobutylene, amine antioxidants, and dimethyl carbonate. This synergistic effect allows the additive to comprehensively optimize the cleanliness, anti-knock properties, stability, and combustion efficiency of fuel at a relatively low total addition amount.

The application discloses an acid-resistant non-noble metal catalyst and a preparation method and application thereof, and particularly relates to the field of acid-resistant metal catalysts, and the preparation method of the acid-resistant non-noble metal catalyst comprises the following steps: step 1, preparation of a carrier; step 2, modification of the carrier; step 3, preparation of an impregnation solution; step 4, preparation of an unactivated catalyst; step 5, activation of the catalyst; and step 6, functionalization of the catalyst. The acid-resistant non-noble metal catalyst prepared by the application can be applied to the synthesis of p-aminophenol from nitrobenzene. The catalyst has good acid resistance and stability, and when applied to the process of preparing p-aminophenol by rearrangement of nitrobenzene hydrogenation, the catalyst has high activity and high selectivity of p-aminophenol under relatively mild reaction conditions, the production conditions are improved, the production cost is reduced, and the product quality is improved.

The present application belongs to the technical field of biomass hard carbon, and particularly relates to a preparation method and application of a high-rate hard carbon negative electrode material. The preparation steps are as follows: biomass raw materials are pre-carbonized under a protective atmosphere to obtain a pre-carbonized product; the pre-carbonized product is added into a p-nitrophenol solution, stirred uniformly, poured into a reaction kettle containing a polytetrafluoroethylene carbonization bottle, and subjected to a hydrothermal reaction in a blast drying oven to obtain pretreated material, which is then crushed to obtain crushed material; the crushed material is subjected to high-temperature heat treatment under an inert atmosphere to obtain heat-treated material; the heat-treated material is mixed with liquid pitch, fused in a high-speed fusion machine to obtain fused material; and the fused material is subjected to surface modification under an inert atmosphere to obtain a high-rate hard carbon negative electrode material after cooling. The finished material can be applied in sodium ion batteries. The present application introduces nitrogen atoms, optimizes defects, improves the sodium ion transmission rate, and improves the rate performance.

This invention discloses 2'-hydroxy-4,4',6'-trimethoxychalcone and 5,7,4'-trimethoxyflavanone sulfonamide derivatives, their synthesis methods and applications, belonging to the field of pharmaceutical technology, and involving two series of compounds: 3-sulfonamido-2'-hydroxy-4,4',6'-trimethoxychalcone and 8,3'-disulfonamido-5,7,4'-trimethoxyflavanone, and their preparation methods. Starting with 2-hydroxy-4,6-dimethoxyacetophenone and p-anisaldehyde or 4-methoxy-3-nitrobenzaldehyde, 2'-hydroxy-4,4',6'-trimethoxychalcone or 3-amino-2'-hydroxy-4,4',6'-trimethoxychalcone intermediates were synthesized via the Claisen-Schmidt reaction. Then, through sulfonation and intramolecular Michael addition reactions, 2'-hydroxy-4,4',6'-trimethoxychalcone and 5,7,4'-trimethoxyflavanone sulfonamide derivatives were synthesized. The preparation method is simple, mild, and yields high results. In vitro and in vivo activity tests show that the derivatives disclosed in this invention have significant in vitro inhibitory activity against gastric cancer, esophageal cancer, colorectal cancer, and lung cancer cell lines, acting as inhibitors of the protein YBX1 / RPN1. Clinically, they can be applied to targeted therapy for cancers such as gastric cancer, esophageal cancer, colorectal cancer, and lung cancer.

The application discloses a preparation method of relugolix and belongs to the field of drug synthesis. The method uses 2-[(2,6-difluorobenzyl) n-propoxy amido]-4-(dimethylamino) methyl-5-(4-nitrophenyl) thiophene-3-carboxylic acid ethyl ester (formula II) as a starting material, and relugolix is prepared through the following steps: inorganic base hydrolysis, amide condensation, inorganic base cyclization, 10% Pd / C catalytic hydrogenation, and finally amide condensation with methoxyamino carbonic acid phenyl ester. The starting material used in the preparation method is cheap and easy to obtain, the reaction is mild, the operation is simple, the product has high purity and high yield, no biuret by-product is detected, and the method is suitable for industrial production.

The application relates to the technical field of anticorrosive paint and discloses long-acting aging-resistant acrylic anticorrosive paint and a production process thereof, wherein the long-acting aging-resistant acrylic anticorrosive paint comprises the following components by weight: 40-50 parts of acrylic emulsion, 4-8 parts of polyester resin, 4-8 parts of amino resin, 3-4 parts of film-forming aid, 20-25 parts of modified talcum powder, 10-12 parts of solvent and 4-5 parts of auxiliary agent; the modified talcum powder is obtained by modifying talcum powder with a modifier, wherein the modifier comprises 2-[(2-methoxy-4-nitrophenyl)amino]ethanol and / or hydroxybutyryl amide phenyl ether. The above technical scheme solves the problem of poor anticorrosive performance of the acrylic anticorrosive paint in the prior art.

The application discloses a preparation method of triclabendazole, and relates to the technical field of raw medicine synthesis. The method comprises the following steps: taking 4-chloro-5-(2,3-dichlorophenoxy)-2-nitroaniline as raw material, and sequentially performing reduction in an iron powder ethanol system, ring closure with a sulfur-containing ring closure reagent, methylation with dimethyl sulfate, and crystallization and purification in ethanol to obtain triclabendazole finished products. In the reaction process, iron mud is removed through pressure filtration, ethanol is recovered through distillation, and the ring closure intermediate is precipitated under acidic conditions. The process condition is clear, the operation is simple, the emission of hazardous waste can be reduced, the utilization rate of solvents and the purity of products can be improved, and the method is suitable for industrialized production of triclabendazole raw medicine.

The application discloses a synthesis method of a trident connecting segment which can be used for improving hydrophilicity of an antibody drug conjugate, and relates to the field of organic synthesis. The {[5-amino-2-(3,3,4,4-tetramethyl-2-oxa-3-silapent-1-yl)phenyl]methyl}(methyl)amino)methane acid-2-methylpropan-2-yl ester can be used for connecting a hydrophobic dipeptide, a hydrophilic chain and a small molecule drug in an ADC drug, so as to prolong the action time of the ADC drug. The application takes cheap and easily obtained commercial raw material 2-bromo-5-nitrobenzaldehyde as a starting raw material, and successfully prepares the target product through seven steps of conventional transformation such as reduction amination, protection, coupling, ozonation and nitro reduction, with a total yield of about 60% and a scale of hundreds of grams. The starting raw material is cheap, the operation and treatment are simple, and the reaction condition is mild, so that the application is a brand-new process synthesis route, and has good economic benefits and market prospects.

A biphenylthiourea carboxylic acid metal organic framework crystal material and a preparation method and application thereof.The material has the following chemical formula: {[Zn4O(L)3]·DMF·H2O} n , wherein L is a 6-thio-6,7-dihydro-5H-dibenzo[d,f][1,3]diazepine-3,9-dicarboxylate divalent anion, and n is a degree of polymerization.The metal organic framework crystal material of the present application is synthesized by a solvothermal method, is simple to operate, has low cost, high yield, and is easy to mass industrial production.The prepared metal organic framework crystal material has a high specific surface area (a BET specific surface area of 594 m 2 / g), and an adsorption amount of CO2 of 46.0 cm 3 / g at 1 atm and 273 K.The biphenylthiourea carboxylic acid metal organic framework crystal material of the present application can efficiently catalyze a Friedel-Crafts alkylation reaction of substituted indole and substituted trans-nitrostyrene to generate an indole 3-substituted derivative, and can also efficiently catalyze a Michael addition reaction of diethyl malonate and substituted trans-nitrostyrene, both of which have mild conditions, and the catalyst can be recycled with almost no activity loss, and are good heterogeneous catalysts.

This invention provides a method for preparing carbon quantum dots, their application in the detection of 4-nitrophenol and curcumin, a concentration detection method, and a visualization detection method. The method involves mixing tris(hydroxymethyl)aminomethane and phloroglucinol in a solvent, followed by heating in a reaction vessel to obtain the carbon quantum dots. This invention provides a simple and low-cost method for preparing carbon quantum dots, enabling rapid and low-cost detection of 4-NP and curcumin, thus meeting the detection needs for both.

The present application relates to the technical field of nitrofurans metabolite content determination, and particularly relates to a method for determining the residual amount of nitrofurans metabolite in propolis. The method is that the pretreated propolis sample is detected by liquid chromatography-tandem mass spectrometry after gradient elution of the mobile phase; the pretreatment is that the propolis sample is sequentially hydrolyzed by hydrochloric acid, purified by HLB solid phase extraction column, derivatized by o-nitrobenzaldehyde, and purified by ethyl acetate treatment. The present application purifies the propolis sample after hydrochloric acid hydrolysis before o-nitrobenzaldehyde derivatization, so that o-nitrobenzaldehyde fully reacts with the nitrofurans metabolite in propolis, and the residual amount of nitrofurans metabolite in propolis is accurately detected by combining the selection and gradient elution of the mobile phase.

This application relates to the field of materials technology, providing a chitosan-polyacrylonitrile composite material, its preparation method, and its application. The general structural formula of the chitosan-polyacrylonitrile composite material is as follows: This application uses inexpensive chitosan and polyacrylonitrile fiber as raw materials to develop a novel chitosan-polyacrylonitrile composite material, overcoming the solubility limitation of chitosan under acidic conditions and simultaneously enhancing its adsorption capacity for phenolic compounds and heavy metals. It exhibits higher selectivity for target pollutants, especially among eight different phenolic compounds (phenol, 4-methylphenol, 4-chlorophenol, 4-nitrophenol, hydroquinone, catechol, resorcinol, and phloroglucinol), showing excellent adsorption performance for hydroquinone, with an adsorption capacity as high as 316.84 mg·g⁻¹. ‑1 Furthermore, this application addresses the soft metal ion Hg. 2+ Its adsorption capacity is outstanding, with a maximum adsorption capacity of 237.18 mg·g⁻¹. ‑1 .

The application discloses a pyrrole ring-containing boron-sulfur doped fused ring aromatic hydrocarbon and a synthesis method and application thereof, and relates to a pyrrole ring-containing boron-sulfur doped fused ring aromatic hydrocarbon which is synthesized from simple raw materials such as 2,6-difluoronitrobenzene through a Clauson-Kaas pyrrole synthesis reaction and an electrophilic boronation reaction. Property research involves ultraviolet, fluorescence and CV tests, and mercury ion tests. The application has the characteristics of a short reaction path, a simple operation method and mild reaction conditions, and the compound has the potential of application in the field of photoelectric devices and can also be applied to mercury ion identification.

This invention belongs to the field of organic chemical synthesis technology, specifically relating to a method for synthesizing 2-fluoro-3-aminobenzoic acid, an important chemical intermediate. Specifically, o-nitroaniline is condensed with hydrated trichloroacetaldehyde and hydroxylamine hydrochloride to obtain 2-(hydroxyimino)-N-(2-nitrophenyl)acetamide; the resulting product undergoes an intramolecular Beckmann rearrangement to generate 7-nitroindigo; 7-nitroindigo undergoes Bayer-Villedge oxidation to generate 2-amino-3-nitrobenzoic acid; 2-amino-3-nitrobenzoic acid undergoes diazotization and halogenation reactions to generate 2-fluoro-3-nitrobenzoic acid or 2-chloro-3-nitrobenzoic acid; 2-fluoro-3-nitrobenzoic acid can be further reduced by nitro to obtain 2-fluoro-3-aminobenzoic acid; or, 2-chloro-3-nitrobenzoic acid can be esterified to obtain 2-chloro-3-nitrobenzoic acid ester, which can then be fluorinated, saponified, and reduced to obtain 2-fluoro-3-aminobenzoic acid. The raw materials of this invention are low in cost and readily available, and the entire reaction route has specific regioselectivity, making it suitable for industrial production.

The application provides a preparation method of 4,6-dichloropyrimidine, which uses 4,6-dihydroxypyrimidine as a starting reaction raw material, halogenated alkane or nitrobenzene as a solvent, triphosgene as a chlorinating reagent, and an organic phosphine as a catalyst, and a morpholine derivative is selected as a cocatalyst. The catalyst and the cocatalyst can be used repeatedly, an acid binding agent is not required in the reaction process, the reaction time is about 3 hours, the product yield is not less than 95.0%, and the method is an efficient and green and environmental 4,6-dichloropyrimidine preparation method.

The application discloses a mixed solid catalyst and application thereof in preparation of p-aminophenyl alkyl ether, wherein the mixed solid catalyst is composed of an activated carbon supported noble metal catalyst and a perfluorosulfonic acid resin with a mass ratio of 1:1-10, and the activated carbon supported noble metal catalyst is one or more than two of Pt / C, Pd / C and Ir / C; the mixed solid catalyst system prepared according to the application realizes continuous reaction and synthesis of p-aminophenyl alkyl ether by using nitrobenzene and an alcohol solution as raw materials, and has its own unique advantages.

This invention provides a method and apparatus for preparing RT-plast condensate using a thin-film reaction. The apparatus consists of a salt-forming filtration unit and a condensation reaction unit, which is further divided into a primary condensation step, a secondary condensation step, and a multi-stage condensation step. The method includes: dehydrating aniline, an organic base, and liquid alkali into salt in a thin-film reactor, filtering to obtain a desalted alkali solution, and then entering the condensation reaction step, where it is mixed with nitrobenzene and dehydrated and condensed to obtain the RT-plast condensate. Using a thin-film reaction apparatus for preparing the RT-plast condensate, the material residence time in the reaction apparatus is only 5-15 minutes, far shorter than the 3-5 hours of continuous batch condensation, significantly improving the efficiency of the condensation reaction.