26 results about "Dimethylaniline" patented technology

The application discloses a synthesis method of 2,3,3',4'-biphenyl tetracarboxylic dianhydride, characterized in that 2,3-dimethylaniline is used as a starting raw material, 2,3-dimethylaniline diazonium salt is prepared through a diazotization reaction, then 2,3,3',4'-tetramethyl biphenyl is prepared through a coupling reaction of the 2,3-dimethylaniline diazonium salt and o-xylene under the catalysis of cuprous chloride, and finally 2,3,3',4'-biphenyl tetracarboxylic dianhydride is prepared through an oxidation reaction and dehydration to form anhydride. The coupling reaction in the synthesis method has good selectivity, 3,3,4',4'-tetramethyl biphenyl which is difficult to separate is not generated, high-purity a-BPDA can be finally obtained, and the coupling reaction in the synthesis method only needs to use low-cost cuprous chloride as a catalyst, so that the production cost is greatly reduced compared to a high-cost catalytic system in the prior art, and the synthesis method is more suitable for industrial mass production.

This invention relates to the field of polyaniline derivative preparation technology, and more particularly to a green preparation method for poly(2,3-dimethylaniline). The green preparation method provided by this invention includes mixing a reaction mother liquor for preparing poly(2,3-dimethylaniline), a nitric acid solution, and 2,3-dimethylaniline, and then adding Fe... 3+ The catalyst is subjected to a first heat treatment, hydrogen peroxide is added, and a second heat treatment is performed to obtain a first-use reaction mother liquor and a filter cake. The filter cake is post-treated to obtain the poly-2,3-dimethylaniline. The first-use reaction mother liquor is recycled according to the above process. During the above recycling process, when the COD content in the reaction mother liquor obtained after recycling is greater than 29000 mg / L, the molar ratio of H2O2 to 2,3-dimethylaniline in hydrogen peroxide is increased based on the molar ratio of H2O2 to 2,3-dimethylaniline in hydrogen peroxide during the first recycling process. The preparation method has high yield and is environmentally friendly.

This invention belongs to the field of stone adhesive technology, specifically relating to a transparent stone splicing adhesive and its preparation method. The adhesive comprises a resin component and a curing component. The resin component includes maleic anhydride, phthalic anhydride, diol, catalyst, polymerization inhibitor, and crosslinking monomers, etc., and the diol includes at least 1,2-propanediol. The curing component includes an accelerator composed of dimethylaniline and zinc adipate, and a benzoyl peroxide initiator. The adhesive of this invention is colorless and transparent after curing, exhibits excellent resistance to yellowing, is easy to apply, and after curing with fillers, possesses excellent shear strength, water shear strength, and impact resistance. It can be widely used in high-end stone splicing, repair, and craft bonding.

The invention discloses a catalyst for preparing N-(1-ethyl propyl)-3, 4-dimethylaniline through continuous catalytic hydrogenation and a preparation method and application thereof, the catalyst comprises a carrier, and an active component platinum and an auxiliary component which are loaded on the carrier, the auxiliary component is at least one of sodium citrate, disodium ethylene diamine tetraacetate, sodium metavanadate, oxalic acid, zirconium oxychloride, yttrium nitrate or sodium carbonate; and the active component and the auxiliary component both account for 0.1-10% of the mass of the catalyst. The catalyst is used for preparing N-(1-ethyl propyl)-3, 4-dimethylaniline through hydrogenation, the reaction can be continuous, the safety performance is better, and the catalyst has high catalytic activity and stability.

This invention relates to a toothpaste flavoring with a long-lasting fresh breath effect and its preparation method. The core component of this toothpaste flavoring is modified menthol. Modified menthol reacts with amino acid compounds to form a menthol-amino acid complex, which is then coated with β-cyclodextrin to form a menthol-amino acid-β-cyclodextrin complex. This dual synergistic effect effectively prolongs the duration of its fresh breath effect. The toothpaste flavoring also includes 2,6-dimethylaniline, flavor enhancers, emulsifiers, stabilizers, aroma retardants, and preservatives to ensure aroma stability and safety for oral use. This invention provides a longer-lasting fresh breath effect, solving the problems of rapid evaporation and short-lasting freshness in traditional toothpaste flavorings, and has good market application prospects.

The present invention relates to the technical field of concrete materials. Disclosed are a modified epoxy resin and a preparation method therefor, a composition for an epoxy resin grouting material, an epoxy resin grouting material, a preparation method therefor, and a use thereof. The method for preparing the modified epoxy resin comprises: heating a polyhydroxy compound and an epoxy resin at 80-100ºC in a nitrogen atmosphere in the presence of a catalyst to obtain the modified epoxy resin, wherein the molar ratio of the polyhydroxy compound, the epoxy resin, and the catalyst is 1:1-2:0.05-0.1; the epoxy resin is a bisphenol A epoxy resin; the catalyst is selected from any one of sodium hydroxide, potassium carbonate, and dimethylaniline; and the polyhydroxy compound is selected from at least one of glycerol, ethylene glycol, propylene glycol, glucose, and butylene glycol. The epoxy resin grouting material of the present invention has more excellent toughness and lower viscosity, and good bonding strength and bonding durability with a concrete matrix.

This invention discloses a berberine-dimethylaniline photosensitizer, its preparation method, and its application, belonging to the field of biomedical technology. The method involves sequentially reacting berberine with magnesium methyl bromide via Grignard addition, followed by bromomethylation with N-bromosuccinimide, and basic condensation with dimethylaminobenzaldehyde, then demethylating under high temperature and vacuum to obtain the active berberine-dimethylaniline. Finally, it undergoes weakly alkaline treatment to obtain the inactivated berberine-dimethylaniline. This invention introduces the electron-donating group dimethylaniline onto the berberine backbone, constructing an electron push-pull structure that red-shifts the absorption wavelength, facilitating deeper tissue penetration. Furthermore, this photosensitizer maintains high activity in the weakly acidic microenvironment of tumors while remaining inactive under normal physiological conditions, thereby achieving intelligent "on-off" regulation based on pH differences, improving the safety and precision of photodynamic therapy for tumors.

The invention belongs to the technical field of pharmaceutical preparations, and relates to lidocaine hydrochloride gel and a preparation method thereof, and the preparation method comprises the following steps: 1) dissolving and dispersing a bacteriostatic agent and a gel matrix with water, and sterilizing to obtain a gel solution; 2) dissolving lidocaine hydrochloride with water, adjusting the pH value of the solution, and performing rapid heating and cooling sterilization to obtain a lidocaine hydrochloride solution; and (3) adding a lidocaine hydrochloride solution into the gel solution under a sterile condition, and stirring and mixing the lidocaine hydrochloride solution and the gel solution. By adjusting and changing the production and preparation process of lidocaine hydrochloride, the exposure time of lidocaine under a high-temperature condition is reduced, the degradation of lidocaine is further reduced, the content level of 2, 6-dimethylaniline is effectively reduced, the stability and quality of the product are improved, and toxic and side effects on patients are reduced; and the production process is simple and convenient to operate, the production time of the lidocaine hydrochloride gel is shortened, the working efficiency is improved, and the cost is saved.

The present disclosure provides for methods of producing analgesia in a subject. In some cases, methods produce analgesia in a subject undergoing arthroscopic subacromial decompression surgery. The present disclosure also relates to improved sustained release drug delivery systems. In some cases, a composition comprises an active pharmaceutical agent; at least one of sucrose acetate isobutyrate and a polyorthoester; an organic solvent; and 2,6-dimethylaniline, wherein the 2,6-dimethylaniline is present at a level less than 500 ppm. In some cases, a composition comprises bupivacaine N-oxide at a level less than 1 wt %, based on weight of the composition. In some cases, a composition comprises metal present at a level less than 5 ppm. Dosage forms and methods are also provided.

The invention belongs to the technical field of organic synthesis, and particularly relates to a preparation method of novel tiamulin fumarate. The preparation method comprises the following steps: reacting pleuromutilin with thionyl chloride to generate chlorinated pleuromutilin; reacting the chlorinated pleuromutilin with thiourea, and carrying out alkali treatment, so as to generate sulfhydrylated pleuromutilin; the preparation method comprises the following steps: reacting sulfhydrylated pleuromutilin with 2-bromo-N, N-diethyl ethyl-1-amine to form tiamulin, and finally carrying out a salt forming reaction. The invention provides a synthetic route of chlorination, sulfhydrylation, alkylation and salification, and two key intermediates, namely the chlorinated pleuromutilin and the sulfhydrylated pleuromutilin, are prepared step by step, so that the accurate control of the reaction process is realized. Wherein the chlorination reaction is catalyzed by N, N-dimethylaniline, the low-temperature staged reaction is adopted, and the selectivity is good; thiourea is used for alkaline hydrolysis in sulfhydrylation, so that foul mercaptan is avoided; alkylation is carried out under weak base and low temperature; no controlled reagent is needed in the whole process, and green chemical requirements are met.

The invention relates to the technical field of hydrogel, in particular to hydrogel based on an acrylonitrile acrylamide copolymerization system and a preparation method of the hydrogel. The preparation method comprises the following steps: preparing a copolymerization solution by taking an acrylonitrile monomer and an acrylamide monomer as raw materials, wherein the molar ratio of the acrylonitrile monomer to the acrylamide monomer is (3: 7)-(5: 5); an initiator is added into the copolymerization liquid, the mixture is subjected to a polymerization reaction at the temperature of 40-50 DEG C, organogel is obtained, and the initiator is composed of dibenzoyl peroxide and N, N-dimethylaniline according to the molar ratio of 1: 1; and replacing the solvent in the organic gel with water. Compared with the prior art, the preparation method has the advantages that acrylamide is utilized to construct a high-hydrophilicity and high-entanglement network framework, so that the material is ensured to have good flexibility and ductility; meanwhile, an acrylonitrile monomer containing a strong-polarity cyano group is introduced, and a high-strength physical cross-linking area is dynamically constructed under the action of external force through dipole-dipole interaction formed by the acrylonitrile monomer, so that network dynamic enhancement and strain hardening response are realized.

The present invention provides a mepivacaine preparation method, which comprises that in an organic solvent, 1-methylpiperidine-2-formic acid and 2, 6-dimethylaniline are subjected to a condensation reaction in the presence of a condensing agent to obtain mepivacaine, and the condensing agent is selected from one or more of phosphorus oxychloride, phosphorus trichloride and phosphorus pentachloride. The condensing agent used for preparing mepivacaine is one or more of phosphorus oxychloride, phosphorus trichloride and phosphorus pentachloride, toxic substances such as phosgene and the like are not generated, the safety is high, the cost is low, and the preparation method is suitable for industrial popularization.

The invention relates to the technical field of preparation of alkylation catalysts, and discloses an alkylation catalyst, a preparation method and application thereof, and a synthesis method of N, N-dimethylaniline. The invention relates to an alkylation catalyst, which comprises Cu, an auxiliary active component and a carrier, the auxiliary active component is selected from at least one of VIII group metal and VIB group metal; the carrier comprises a molecular sieve and a binder; wherein the ratio of Cu < + > to Cu < 2 + > in the catalyst is 0.1-0.4. The catalyst has a specific Cu < + > / Cu < 2 + > ratio, and the activity, the stability and the service life of the catalyst can be improved.

This invention discloses a poly(2,5-dimethylaniline), its preparation method, and its applications, belonging to the field of polymer materials technology. First, deionized water, an inorganic acid, and 2,5-dimethylaniline are stirred and mixed evenly; then, ammonium persulfate solution is slowly added dropwise to initiate a polymerization reaction; after a certain time of isothermal polymerization, the mixture is filtered, washed, dried, and ground to obtain the poly(2,5-dimethylaniline). The poly(2,5-dimethylaniline) prepared by this invention has a high corrosion potential, the raw materials are readily available, the preparation method is simple and easy to implement, and it has broad development prospects.

The application discloses a catalyst for continuously preparing N-(1-ethylpropyl)-3,4-dimethylaniline through hydrogenation as well as a preparation method and application thereof. The catalyst comprises a carrier, and an active metal Pt, a first additive and a second additive supported on the carrier; the first additive is one of Sb, V, Zr, Ti and W, and the second additive is one of Bi, Co, Zn, Mn and La; the content of each component in the catalyst with a mass of 100% is as follows: the active metal Pt is 0.5-5%, the first additive is 0.1-1%, the second additive is 0.05-0.2%, and the rest is the carrier. The carrier is pretreated by using the additive metal, so that the catalyst has excellent anti-sintering and anti-carbon deposition capacity in continuous operation, and has a long service life; when the N-(1-ethylpropyl)-3,4-dimethylaniline is prepared, a continuous flow fixed bed technology is adopted, and production efficiency is high.

The invention discloses a method for preparing 2, 4-dimethylaniline through direct ammonification of 2, 4-dimethylphenol. Comprising the following steps: contacting a raw material of 2, 4-dimethylphenol with a catalyst, and reacting in the presence of an ammonia source to obtain a product containing 2, 4-dimethylaniline, the catalyst is a nickel modified ZSM-12 molecular sieve. According to the present invention, 2, 4-dimethylaniline is prepared from 2, 4-dimethylphenol through a new path by using a one-step method, the catalyst is prepared by using a simple impregnation method, the catalyst comprises non-noble metal nickel and a ZSM-12 molecular sieve, and the metal and the carrier of the catalyst interact so as to produce 2, 4-dimethylaniline with high selectivity; the method has the advantages of low catalyst cost, simple process route, low reaction pressure and low equipment investment, and is suitable for large-scale and long-period continuous production.

The invention belongs to the technical field of coatings, and relates to high-temperature-resistant CHPO cured putty and a preparation method thereof, and the high-temperature-resistant CHPO cured putty comprises the following components: unsaturated polyester resin, styrene, cobalt iso-octoate, dimethylaniline, a high-temperature-resistant composite dispersant, hydrogenated castor oil, silicon dioxide, rutile titanium dioxide, talcum powder and a curing agent.

This application provides a conjugated bridged azobenzene fluorescent molecule, its synthesis method, and its application, belonging to the field of adsorption materials technology. The fluorescent molecule is (5... Z ,11 Z) -4,4'-dibenzo[ c , g [1,2]bis(azaoctyl-2,9-diyl)diphenylamine, (5 Z ,11 Z) -4,4'-dibenzo[ c , g [1,2]bis(azaoctyl-2,9-diyl)bis( N , N (5-dimethylaniline), (5-dimethylaniline) Z ,11 Z) -4,4'-dibenzo[ c , g [1,2]bis(azaoctyl-2,9-diyl)bis( N , N This application describes the functionalization modification of a fully conjugated β-Azo molecule by introducing an electron-rich aniline group. This not only increases the Stokes shift of the molecule, effectively avoiding spectral overlap between excitation and emission light, but also causes a red shift in the emission wavelength, further improving its optical properties. Its application as a fluorescent probe and in iodine adsorption demonstrates good performance.

The application relates to a method for efficiently preparing a key intermediate of sulfonamide chloropyridazine, characterized by the following steps: in an organic solvent, taking phosphorus oxychloride and 3,6-dihydroxypyridazine as raw materials, a mixed solution of 2-methylpyridine and N,N-dimethylaniline as an acid-binding agent, and N,N-dimethylformamide as a catalyst to perform a chlorination reaction. The method changes the previous process of directly using phosphorus oxychloride and 3,6-dihydroxypyridazine, and improves the method by adopting dichloroethane as a solvent, a mixed solution of 2-methylpyridine and N,N-dimethylaniline as an acid-binding agent, and N,N-dimethylformamide as a catalyst to perform a chlorination reaction. The improved method reduces by-products (high-purity products can be obtained without refining 3,6-dichloropyridazine again), the reaction is more moderate, safe and controllable, the recovery and reuse operation of the solvent and the acid-binding agent is simple, the post-treatment is more stable, and high-yield and high-purity 3,6-dichloropyridazine can be prepared.

The invention discloses a preparation method of an antiviral drug amonevir. The method comprises the following steps: pumping sulfurized cyclopentane-4-formyl chloride prepared in situ and 2, 6-dimethylaniline into a first microchannel reactor, and carrying out an amidation reaction; pumping the obtained amide intermediate, potassium tert-butoxide and bromoacetic acid into a second microchannel reactor, and carrying out a second amidation reaction; pumping the generated product, 4-(1, 2, 4-oxadiazole-3-yl) aniline and a condensing agent into a third microchannel reactor, and carrying out a third amidation reaction; pumping the obtained product and hydrogen peroxide into a fourth micro-channel reactor for oxidation reaction to obtain an amonevir crude product; and after the crude product is subjected to extraction, concentration and ethanol recrystallization, an amonevir product with liquid phase purity of 99.9% is obtained. And the tautomer of the amonevir can be simply and efficiently separated by utilizing the detection method disclosed by the invention, and a reliable guarantee is provided for industrial production of the amonevir.

This invention relates to the field of polyaniline derivative preparation technology, and more particularly to a method for preparing poly2,3-dimethylaniline. The invention provides a method for preparing poly2,3-dimethylaniline, comprising the following steps: mixing nitric acid solution and 2,3-dimethylaniline until completely dissolved, and adding Fe... 3+ The catalyst is subjected to a first heat treatment, hydrogen peroxide is added, and a second heat treatment is performed to obtain the poly(2,3-dimethylaniline); the molar ratio of nitric acid to 2,3-dimethylaniline in the nitric acid solution is (0.95~1.3):1. The poly(2,3-dimethylaniline) prepared by the above method has a high yield, reaching over 90%.

This invention discloses a D-Π-A structured copper cluster metal-covalent organic framework material and its application in photocatalytic nitrification reactions, relating to fields such as energy, materials, organic synthesis, and biomedicine. The material is synthesized via a solvothermal method using a cyclic trinuclear copper cluster unit (CuL3 cluster) as the metal node, along with tris(4-formylphenyl)amine (TFPA) and p-phenylenediamine (PA), to construct a copper cluster metal-covalent organic framework (Cu3-TFPA-MCOF) with an imine-linked structure. The resulting material exhibits excellent charge separation efficiency and electron mobility, and can efficiently catalyze reactions under blue LED irradiation. N,N The nitrification reaction of dimethylaniline and its derivatives. The method of this invention features broad substrate universality and good functional group compatibility. The catalyst maintains high activity after multiple cycles, demonstrating good stability and sustainability. This research not only significantly improves the charge separation efficiency and catalytic performance in the photocatalytic process, but also provides new design ideas and preparation routes for developing environmentally friendly, structurally tunable imine-linked copper cluster MCOF photocatalysts.

The invention provides a method for simultaneously detecting the content of N-methylaniline and N, N-dimethylaniline in quetiapine fumarate, the method adopts an ultra-high performance liquid chromatography and mass spectrometry technology, a chromatographic column is a phenyl-hexyl chromatographic column, a water phase of a mobile phase is a formic acid aqueous solution, and an organic phase of the mobile phase is acetonitrile or methanol. The method is good in specificity, high in accuracy, high in sensitivity and high in durability, and the quality of quetiapine fumarate can be effectively monitored.

The invention belongs to the technical field of fluorescence detection materials, and particularly discloses an open type colorimetric fluorescence covalent organic polymer and preparation and application thereof.The preparation method comprises the following steps that 4, 4 ', 4' '-(1, 3, 5-triazine-2, 4, 6-triyl) tri (2, 6-dimethylaniline) and trialdehyde phloroglucinol are dissolved in 1, 4-dioxane; performing ultrasonic treatment and uniformly adding acetic acid; circulating and degassing by a freezing pump for three times, and carrying out heating reaction; performing Soxhlet washing through tetrahydrofuran and dichloromethane in sequence; and drying, passing through a 200-mesh screen, and carrying out dry grinding. According to the open-type colorimetric fluorescent covalent organic polymer as well as the preparation and the application thereof, the open-type colorimetric fluorescent covalent organic polymer is sensitive in reaction with semicarbazide and 3, 5-dinitro-2-hydroxyphenylene hydrazine and can be used for an open-type fluorescent chemical sensor, so that the influence of other impurities on a detection result is reduced; and the detection sensitivity is improved.

The invention belongs to the technical field of herbicides, and aims to solve the problems of high safety risk, low production efficiency and poor product quality caused by the adoption of dangerous reagents and intermittent processes in the existing preparation of cyclopyridazinate. In order to achieve the purpose, the invention provides the cyclopyridazinofop-methyl, the green continuous synthesis method of the cyclopyridazinofop-methyl and the application of the cyclopyridazinofop-methyl in the herbicide, and the method comprises the following steps: carrying out continuous diazotization, photocatalysis and ionic liquid extraction and purification on 2, 6-dimethylaniline to prepare 2-cyclopropyl-6-methylphenol; the preparation method comprises the following steps: carrying out continuous cyclization, electrochemical chlorination and continuous hydrolysis on maleic anhydride and hydrazine hydrate to prepare 6-chloro-3, 4-dihydroxypyridazine; 2-cyclopropyl-6-methylphenol and 6-chloro-3, 4-dihydroxypyridazine are subjected to ionic liquid catalytic coupling, immobilized enzyme catalytic acylation and continuous crystallization purification, and finally the cyclopyridazinyl is obtained. According to the method, a continuous preparation process is adopted, and a highly toxic reagent is avoided, so that the preparation safety of the cyclopyridazinate is ensured, and the production efficiency and the product quality are improved.

The application discloses a catalyst for synthesizing 2,6-dimethylaniline, which is composed of a carrier, active metal Pd supported on the carrier and auxiliary metal; the auxiliary metal comprises auxiliary metal A and auxiliary metal B, the auxiliary metal A is one of K and Na, and the auxiliary metal B is at least two of Ba, Zn, Mg, Zr and La; the carrier is alumina; according to 100% of the total weight of the catalyst, the percentage of each component is as follows: 0.2-2% of the active metal Pd, 0.1-3% of the auxiliary metal A, 0.1-10% of the auxiliary metal B, and the balance is the carrier. Meanwhile, the application also discloses a preparation method of the catalyst and application of the catalyst in preparation of 2,6-dimethylaniline. The catalyst provided by the application is applied to continuous catalytic synthesis of 2,6-dimethylaniline from 2,6-dimethylphenol, the yield of the target product is higher, and the service life of the catalyst is good.