26 results about "Methylating Agent" patented technology

The present application relates to a kind of preparation method of trifluoromethyl pyrazole compound, belong to the technical field of organic synthesis.The specific method is: (1) trifluoroacetyl ethyl acetate is first with hydrazine hydrate cyclization reaction and generates compound of formula III;(2) under the catalysis of base, compound of formula III is reacted with difluoromethylation reagent and generates compound of formula II;(3) compound of formula II is reacted with methylating agent and obtains compound of formula I;The difluoromethylation reagent is difluoro-monochloromethane or sodium difluoro-monochloroacetate;The methylating agent is chloromethane, bromomethane, iodomethane, dimethyl sulfate or dimethyl carbonate.The present application is prepared by changing reaction route, and the higher-priced raw material methylhydrazine is replaced, and isomer impurity is no longer generated in the product prepared.Not only raw material cost is reduced, but also the purity of product is improved.

The application discloses an amplification preparation method of dimethylheptyl methylphosphonate, and belongs to the technical field of medical intermediates. The core point of the application is that 2-octanol and phosphorus trichloride are used as raw materials, and tri-2-octyl phosphite is generated in an organic solvent in the presence of a catalyst A, then the tri-2-octyl phosphite is reacted with a methylating agent in the presence of a catalyst B to generate dimethylheptyl methylphosphonate. The method avoids the use of dangerous reagents and expensive reagents, reduces the raw material cost, reduces the generation amount of isomers, improves the reaction yield, greatly reduces the amount of three wastes, and makes the whole preparation process more green and environment-friendly. The process is simple and reliable, easy to industrial production, and provides a new reaction path for the synthesis of dimethylheptyl methylphosphonate.

This invention discloses a method for iron-catalyzed methylation of quinone compounds, comprising the following steps: in a solvent, using 2-aryl-2-propanols as methylating agents, peroxides as oxidants, iron as catalysts, and amino acids or their derivatives as ligands, oxidizing the C(sp) group of aromatic compounds. 2 The H-bond undergoes methylation to generate methyl-substituted quinone compounds. This invention offers advantages such as readily available, inexpensive, and environmentally friendly catalysts; readily available, inexpensive oxidants that do not generate hazardous waste; mild, stable, and inexpensive methylating agents; mild reaction conditions with high selectivity and high yield; widely available and stable substrates; good compatibility of substrate functional groups and a wide range of substrate applications; compatibility with complex molecules and natural products, enabling effective methylation of quinone compounds. Under optimized reaction conditions, the yield of the target product after separation can reach 80%.

This invention discloses a method for synthesizing potassium 4-methoxysalicylate based on supramolecular-assisted methylation, belonging to the field of organic synthesis technology. The process is based on supramolecular chemistry principles and includes the following steps: (1) Preparation of a macrocyclic host molecule-methylating agent complex loaded with a methylating agent: The macrocyclic host molecule and the methylating agent are reacted at pH 7-9 and 25-40℃ to form a complex solution; (2) One-pot preparation of the target product: 2,4-dihydroxybenzoic acid is salted with potassium hydroxide, potassium carbonate is added, and the above complex solution is added dropwise. A selective methylation reaction is carried out at 55-65℃. After the reaction is complete, post-treatment yields the product. This invention utilizes the molecular recognition function of the macrocyclic host to achieve highly selective methylation of the 4-hydroxyl group under mild conditions. This process has the advantages of simple operation, high safety, low waste, and recyclable host molecules. The yield of potassium 4-methoxysalicylate can reach over 85%, and the purity exceeds 99.0%.

This invention discloses a method for preparing diosmin impurity compounds and their application, relating to the field of pharmaceutical impurity preparation technology. The preparation method includes the following steps: S1, preparation of compound IM-1: compound SM-1 and a methylating agent are heated under alkaline conditions to obtain compound IM-1; S2, preparation of compound formula 1: compound IM-1 is added to an alcohol solution, and an inorganic base is added under stirring. After the addition is complete, the mixture is kept warm and stirred, then cooled to 15-20°C, and dilute hydrochloric acid is added dropwise until the pH reaches 6.5-7. The mixture is concentrated to obtain the crude product of formula 1, and finally purified by thin-layer chromatography to obtain the pure product of formula I. This product can be used as a reference standard for the quality control of diosmin raw material, which helps to obtain a higher quality product.

The application belongs to the field of medicine and provides a new method for preparing a lumerabenzine intermediate compound shown in formula II. The method is that a compound of formula I is reacted with a methylating agent in the presence of an acid binding agent, an organic solvent and water to prepare a compound of formula II. The reaction can be carried out at a lower temperature, high-pressure reaction containers and flammable and explosive materials are avoided, energy consumption is lower, post-reaction treatment is simple, and the method is suitable for industrial production.

This invention provides a method for synthesizing 4-methoxypyrrole derivatives, relating to the field of organic chemical intermediate synthesis technology. The 4-methoxypyrrole derivative is prepared by first reacting m-difluorobenzene as a starting material with oxaloyl chloride monoester under Lewis acid catalysis. The reaction product then undergoes cyclization with aminopropionitrile under alkaline conditions. The subsequent product reacts with methanol in a boron trifluoride complex, followed by methylation with a methylating agent under alkaline conditions. This invention overcomes the shortcomings of existing technologies, providing a simple, low-cost, and easily industrialized method for preparing 4-methoxypyrrole derivatives. It offers advantages such as readily available raw materials, high yield, good quality, simple operation, and suitability for industrial production.

The present application relates to a kind of toluene, methylating agent is obtained in the production method of paraxylene concentration greater than 80% of dimethylbenzene with water vapor as medium to promote reaction.The main problem is that in the existing toluene shape selective methylation fixed bed reaction process, hydrogen and / or nitrogen are used as carrier gas to promote the reaction, which causes high fixed equipment investment, high device material requirements and other problems.The present application solves the problem by shape selective methylation of toluene and methylating agent, adding water vapor instead of hydrogen and / or nitrogen as carrier gas as medium to promote the reaction, and the catalyst para-selectivity is 80-95%, the laboratory life can reach 1000 hours, which can better solve the problem.The method has the advantages of high product purity, no complex separation, simple operation, low fixed asset investment, low material consumption, etc., and can be used for the industrial production of paraxylene.

This invention provides an ionic polymer based on fluorophenyl crosslinked polyarylpiperidine, its preparation method, and its applications, belonging to the field of polymer materials technology. The preparation method includes the following steps: placing a fluorophenyl crosslinking agent, an N-substituted R-4-piperidine, a ketone reactant, and an aromatic reactant in a first organic solvent, adding an acid catalyst to react and obtain a polymer solution with a piperidine structure; subsequently, washing, filtering, and drying in a first precipitant to obtain a polymer powder with a piperidine structure; then dissolving it in a second organic solvent, adding a methylating agent and a basic reagent to react and obtain a quaternized polymer solution; subsequently adding it to a second precipitant, washing, filtering, and drying to obtain an ionic polymer containing fluorophenyl crosslinked polyarylpiperidine. This invention provides a simple preparation method with low raw material costs and is suitable for large-scale production, applicable to fields such as water electrolysis.

This invention belongs to the field of new materials and polymer materials, and relates to an in-situ ATRP-initiated organic / inorganic hybrid anion exchange membrane and its preparation method. The specific steps are as follows: using brominated carbon nanotubes as an initiator, the atom transfer radical polymerization of N,N-dimethylaminomethyl methacrylate is initiated; further, a quaternary ammonium functional ion is added through a Mensutkin reaction with a methylating agent, thereby obtaining an organic / inorganic hybrid anion exchange membrane material initiated by in-situ atom transfer radical polymerization (ATRP). The anion exchange membrane material prepared by this invention possesses both ionic conductivity and dimensional stability, exhibiting excellent performance in alkaline water electrolysis and fuel cells, and can also be used in anion dialysis, etc. This invention is simple and easy to implement, the raw materials can be industrially produced, and it has broad application prospects.

The application discloses a method for removing half ester in bisphenol A bis(diphenyl phosphate), relates to the technical field of organic synthesis, and has the following steps: mixing bisphenol A bis(diphenyl phosphate) material containing half ester with a methylating agent in the presence of a Lewis acid catalyst to make P-OH groups in the half ester undergo a methylation reaction, wherein the methylating agent is selected from one or more of dimethyl phosphate, dimethyl carbonate and dimethyl sulfate; and performing vacuum distillation on the reaction material after the reaction is completed to remove unreacted methylating agent and by-products, and further performing solvent dissolution, acid washing, alkali washing, water washing and desolvent treatment. The method has the beneficial effects that the half ester impurities containing acidic P-OH groups are converted into corresponding phosphate esters through the methylation reaction, and the half ester content and acid value in the BDP product are reduced.

The invention relates to the field of N-methylaniline production, and discloses a method for continuously producing N-methylaniline. The method comprises the following steps: synthesizing N-methylaniline, regenerating a solvent of a spent catalyst, and returning the regenerated catalyst to the synthesis of N-methylaniline for reuse, the synthesis of the N-methylaniline comprises the following steps: in the presence of a fresh catalyst, reacting a methylation reagent with aniline to obtain a spent catalyst; the fresh catalyst comprises a molecular sieve, an inorganic oxide and a modified component, and the modified component is selected from at least one of copper, alkali metal, alkaline earth metal and iron; the sum of the weak acid amount and the middle weak acid amount of the fresh catalyst accounts for more than 80% of the total acid amount; the regeneration of the solvent of the spent catalyst comprises the following steps: sequentially carrying out first-stage solvent regeneration, second-stage hydrogen regeneration and third-stage solvent hydrogen regeneration on the spent catalyst. According to the method, complete regeneration of the deactivated catalyst can be realized, the stability of the catalyst is improved, and long-period operation of the device and continuous production of N-methylaniline are realized.

The application discloses a process for the preparation of saflufenacil comprising reacting 2-chloro-5-(2,6- dioxo-4-(trifluoromethyl)-3,6-dihydropyrimidin-l(2H)-yl)-4-fluoro-N-(N-isopropyl-N- methylsulfamoyl)benzamide with a methylating agent in the presence of a phase transfer catalyst to obtain a final reaction mixture comprising saflufenacil and the phase transfer catalyst, characterized in that the phase transfer catalyst is removed or partially removed before separating or purifying saflufenacil.

The invention relates to the field of N-methylaniline production, and discloses a method for producing N-methylaniline. The method comprises the following step: in the presence of a catalyst, reacting reaction raw materials, namely a methylation reagent and aniline, the catalyst comprises a molecular sieve, an inorganic oxide and a modified component, and the modified component is selected from at least one of copper, alkali metal, alkaline earth metal and iron; wherein the sum of the amount of weak acids and the amount of medium and weak acids in the catalyst accounts for more than 80% of the total acid amount. When the method provided by the invention is used for producing the N-methylaniline, the selectivity of the target product N-methylaniline is relatively high.

This invention discloses a method for preparing cyclopentanone and its intermediates. Specifically, this invention discloses a method for preparing a compound as shown in formula (II), which includes the following steps: Step S1: In a solvent, under the action of a base, cyclopentanone undergoes a methylation reaction with a methylating agent to prepare a crude compound as shown in formula (I); Step S2: In a solvent, under the action of a base, the crude compound as shown in formula (I) undergoes a condensation reaction with p-chlorobenzaldehyde to prepare a compound as shown in formula (II).

The application relates to a phenanthridone skeleton-containing compound and a preparation method and application thereof, and belongs to the technical field of chemical synthesis. The preparation method of the phenanthridone skeleton-containing compound comprises the following steps: S1, a substitution reaction of compound 1 and an alkylating agent to obtain compound 2; S2, hydrolysis of an ester bond of compound 2 to obtain compound 3; S3, reaction of compound 3 and compound 4 to obtain compound 5; S4, a substitution reaction of compound 5 and an alkylating agent to obtain compound 6; S5, intramolecular coupling reaction of compound 6 to obtain compound 7; S6, reduction reaction of compound 7 to obtain compound 8; S7, reaction of compound 8 and a methylating agent to obtain compound 9; and S8, reaction of compound 8 and an alkylating agent to obtain compound 10. The application provides a simple and mild synthesis method for natural active products which can only be extracted from secondary metabolites of marine fungi aspergillus and have limited sources.

The application discloses a kind of 4,16 bis (m-methoxyphenyl) -[2,2] -p-xylene ring diatomic for preparing parylene coating resistant to electrochemical corrosion and its preparation method and application, specifically relates to a kind of 4,16 bis (m-methoxyphenyl) -[2,2] -p-xylene ring diatomic, its preparation method includes the following steps: S1, p-xylene ring diatomic is reacted with liquid bromine in the presence of catalyst, first solvent, and intermediate 1 is obtained;S2, intermediate 1 is reacted with 3-hydroxyphenylboronic acid in the presence of base salt, palladium catalyst and second solvent, and intermediate 2 is obtained;S3, intermediate 2 is reacted with methylating agent in the presence of base salt, third solvent, and the ring diatomic monomer is obtained.The phenyl parylene coating prepared from the above monomer shows excellent resistance to electrochemical corrosion, compared with the corrosion-resistant coating formed by the existing parylene monomer, not only the corrosion current density is low, and corrosion potential is high, has good application prospect in electronic product protection or medical instrument protection and the like.

This invention relates to carbon-13 labeled psychoactive substances, the chemical structural formula of which is: . This invention also provides a method for preparing the aforementioned carbon-13 labeled psychoactive substances, comprising the following steps: (1) 13 C-C3-alanine reacts with Boc2O and a methylating agent to form N-methyl-N-Boc- 13 (2) The product obtained in step (1) is reacted with N,O-dimethylhydroxylamine to obtain an intermediate; (3) The intermediate obtained in step (2) is reacted with a phenyl nucleophile to obtain 13 C-C3-2-N-Boc-methylamino-1-phenyl-1-propanone; (4) The product obtained in step (3) is subjected to a Boc protecting group removal reaction to obtain the carbon 13-labeled psychoactive substance. The present invention also provides the use of the carbon 13-labeled psychoactive substance in detecting the content of methcathinone in biological or environmental samples.

Anticancer conjugates combining a DNA methylation agent and an anticancer drug are provided herein, as well as uses of the same in cancer treatment.

The application discloses a kind of (2-carboxyethyl) dimethyl sulfonium chloride and L-homoserine lactone hydrochloride coproduction method, it is related to organic chemistry technical field;Step is: acrylic acid, L-methionine is dissolved in deionized water, and solution A is obtained;Solution A is reacted with hydrochloric acid, distillation to no distillate under reduced pressure, cooling crystallization, filtration, and L-homoserine lactone hydrochloride is obtained;The filtrate of filtration is dissolved into organic solvent after distillation under reduced pressure, catalyst is added, and is reacted with methylating agent, then distillation to no distillate, add hydrochloric acid, cooling crystallization, filtration, and (2-carboxyethyl) dimethyl sulfonium chloride is obtained;The application uses L-methionine, acrylic acid and hydrochloric acid as raw materials, while preparing L-homoserine lactone hydrochloride, its byproduct beta-methylthiopropionic acid can further prepare (2-carboxyethyl) dimethyl sulfonium chloride, waste is treasure, improves raw material utilization, and three wastes are less, and production cost is low.

The application relates to the technical field of drug intermediate synthesis, in particular to an anti-platelet reduction drug romiplostim intermediate and a preparation method thereof. The method of the application is as follows: starting from compound I, i.e. 2-halogenated phenol, reacting with paraformaldehyde to obtain compound II; the compound II is reacted with a methylating agent and a Grignard reagent in sequence to obtain intermediate IV; the alcohol hydroxyl group in the intermediate IV is oxidized to obtain compound V; the halogen in the compound V is replaced by a cyano group to obtain intermediate VI; the intermediate VI is subjected to asymmetric reduction to obtain intermediate VII; the hydroxyl group in the intermediate VII is continuously protected to obtain intermediate VIII, the cyano group in the intermediate VIII is subjected to a Grignard reaction to obtain intermediate IX; the intermediate IX is subjected to bromination to obtain compound X; and the compound X is ring-closed with thiourea to obtain intermediate XI. The synthesis route of the application avoids column chromatography in each step, is easy to operate, and the reaction yield of each step is relatively high, and can all reach more than 80%.

The invention discloses a cyclic dimer monomer for preparing a parylene coating resistant to electrochemical corrosion as well as a preparation method and application of the cyclic dimer monomer, and particularly relates to a 4, 16-bis (m-methoxyphenyl)-[2, 2]-p-xylene cyclic dimer, the preparation method of the cyclic dimer monomer comprises the following steps: S1, reacting the p-xylene cyclic dimer with liquid bromine in the presence of a catalyst and a first solvent to obtain a p-xylene cyclic dimer; an intermediate 1 is obtained; s2, reacting the intermediate 1 with 3-hydroxyphenylboronic acid in the presence of alkali salt, a palladium catalyst and a second solvent to obtain an intermediate 2; and S3, reacting the intermediate 2 with a methylation reagent in the presence of alkali salt and a third solvent to obtain the cyclic dimer monomer. The benzene-substituted parylene coating prepared from the monomer shows excellent electrochemical corrosion resistance, and compared with a corrosion-resistant coating formed by an existing parylene monomer, the benzene-substituted parylene coating is low in corrosion current density and high in corrosion potential and has a good application prospect in the aspects of electronic product protection or medical instrument protection and the like.

The invention relates to the technical field of organic synthesis, in particular to L-selenium-methyl selenocysteine and a continuous production method and system thereof. The production method comprises the following steps: S1, conveying a reducing agent, selenium powder and an acid solution into a dynamic tubular reactor for reaction to obtain hydrogen selenide gas; s2, the hydrogen selenide gas reacts with a bicarbonate solution to obtain selenium hydride salt, the selenium hydride salt reacts with a methylation reagent to obtain methyl selenol salt, and the methyl selenol salt reacts with a chloro-alanine salt solution to obtain L-selenium-methyl selenocysteine salt; s3, the L-selenium-methyl selenocysteine salt is subjected to acidification, and L-selenium-methyl selenocysteine is obtained; wherein the reaction in the step S2 is carried out in the microchannel reactor. According to the method disclosed by the invention, continuous production of the L-selenium-methyl selenocysteine can be realized, the reaction efficiency is improved, and possibility is provided for mass production.

This invention discloses a continuous flow synthesis method for olutanib, belonging to the field of pharmaceutical synthesis technology. The method involves mixing a solution of 2-cyano-5-fluoropyridine with an acidic solution of hydrogen peroxide and reacting the mixture in a first continuous flow reactor at 70-90°C to obtain intermediate 3; mixing a solution of 3 with an acid anhydride and reacting the mixture in a second continuous flow reactor at 90-100°C to obtain intermediate 4; pumping a solution of 4 and a methylating agent into a third continuous flow packed bed reactor and reacting the solution at 20-25°C to obtain intermediate 5; and then reacting intermediate 5 with (… S A solution of 3-(1-aminoethyl)-6-chloroquinoline-2(1H)-one was pumped into a fourth continuous flow packed bed reactor and reacted at 90-95°C. The resulting product was then purified to obtain olutanib. The total residence time of this method is only 118 minutes, eliminating the need for column chromatography purification. The process is continuous, safe, and controllable, with high production efficiency and ease of scale-up.

The invention belongs to the technical field of organic synthesis, and discloses a preparation method of oxime ether and methoxyamine hydrochloride. According to the method, tert-butyl alcohol is used as a solvent, a methylation reagent, sodium hydroxide, ketoxime and the solvent are subjected to a condensation reaction, reaction liquid is subjected to rectification separation, fractions are collected, and oxime ether is obtained; and mixing the tower bottom residual liquid with a hydrochloric acid solution, and carrying out hydrolysis reaction to obtain methoxyamine hydrochloride. Efficient dissolution of a methylation reagent is achieved through a tert-butyl alcohol solvent system, an oxime ether intermediate is prepared in cooperation with a low-temperature condensation reaction, a hydrochloric acid hydrolysis reaction is completed in a tower after rectification separation, and finally methoxyamine hydrochloride and sodium chloride are obtained. And through solvent innovation, process integration and premixing control technologies, the reaction selectivity is remarkably improved, and the raw material consumption is reduced.

The application belongs to the field of pharmaceutical chemical industry, and particularly relates to a production method of a key intermediate of alamorelin, i.e. trimethylhydrazine hydrochloride. The technical scheme of the application comprises the following steps: step 1. synthesis of compound 2 is divided into two stages: stage 1. under the action of an alkali, hydrazine formic acid tert-butyl ester is reacted with a methylating agent to generate a mixture of compound 3 and compound 2. The mixture does not need to be further purified and separated, and is directly used in the second stage; stage 2. the mixture in the above step is further reacted with the methylating agent to be completely converted into compound 2, and step 2. compound 2 is removed from Boc protection in the presence of hydrochloric acid, and is salified to obtain trimethylhydrazine hydrochloride. The application provides a preparation method of trimethylhydrazine hydrochloride suitable for industrial production, and solves the problems of high production cost and safety hazards existing in the prior art.