288 results about "Transmethylation" patented technology

The present invention discloses an imidazole derivative, a preparation method thereof, and an application, belonging to the field of organic chemistry. The preparation method of the imidazole derivative of the present invention includes: adding compound 2a and dimethyl sulfate into an organic solvent, heating and reacting to obtain compound 3a; wherein, compound 2a is prepared by adding compound 1a, TrtCl, and a base reagent into a solvent, controlling the temperature at 0-10 °C, mixing evenly and reacting. The present invention also further prepares 2-(1-methylimidazol-5-yl)ethylamine (4a) by using the imidazole derivative. The present invention selects dimethyl sulfate as a methylation reagent and cooperates with a specific protecting group design to achieve the efficient preparation of 2-(1-methylimidazol-5-yl)ethylamine, with a total yield of 82.4%.

The purpose of the present invention is to provide a method for producing a methyl compound. Provided is a method for producing a methyl compound using formic acid.

The invention relates to the technical field of tetramethyltin synthesis, in particular to a high-efficiency tetramethyltin synthesis process which comprises the following steps: S1, material selection and preparation: selecting corresponding raw materials according to tetramethyltin synthesis requirements, dividing the raw materials into main materials, auxiliary materials and additives, and subsequently weighing the raw materials by using a weighing device; s2, material pretreatment: adding the weighed main material into a dehydration device, starting the dehydration device to carry out dehydration treatment, detecting after dehydration is finished, and taking out the dehydrated main material when a detection result meets a standard; by introducing the double-stage design of low-temperature catalytic methylation and gradient heating reaction and combining a dimethyl sulfide catalytic system to replace a traditional iodine initiator and magnesium powder dynamic equilibrium mechanism, the reaction heat release rate is greatly reduced, the temperature in the whole reaction process is kept in a constant range, the material flushing or explosion risk caused by local overheating is thoroughly eliminated, and the product quality is improved. And intrinsically safe production is realized.

This invention belongs to the field of chemical synthesis and relates to a method for achieving deuterated methylation of a nucleophile. The invention provides a deuterated methylating reagent, which is obtained by reacting formic acid with deuterated methanol under acidic conditions, followed by a second reaction with thiaanthracite and trifluoromethanesulfonic acid. The nucleophile is then reacted with the deuterated methylating reagent described in claim 1, a base, and a solvent to obtain the deuterated methylated product. This invention also provides a method for achieving deuterated methylation of a nucleophile, which involves dissolving the nucleophile and 5-deuterated methyl-5H-thiophene-5-onium trifluoromethanesulfonate in a suitable solvent, adding a base, and then performing the deuterated methylation reaction at room temperature. In the method provided by this invention, the yield of the product after nucleophile methylation can reach 52% to 95%.

The invention relates to an L-proline heterocyclic intermediate, alpha-methyl-L-proline hydrochloride and a preparation method thereof, which comprises the following steps: step 01, cyclization upper protection: taking L-proline as a raw material, which is shown in a formula (1), to react with trichloracetic aldehyde hydrate under an acidic condition, and performing upper protection to obtain a heterocyclic intermediate as shown in a formula (2); the molar weight of chloral hydrate is 1-2.5 times of the molar weight of the L-proline shown in the formula (1), preferably 1.5 times of the molar weight of the L-proline shown in the formula (1). 02, methylation: reacting the heterocyclic intermediate as shown in the formula (2) obtained in the step 01 with lithium diisopropylamide, and after the reaction is completed, adding dimethyl sulfate for methylation to obtain an intermediate as shown in a formula (3); 03, deprotection: adding the intermediate as shown in the formula (3) obtained in the step 02 into a deprotection reagent for hydrolysis so as to obtain the alpha-methyl-L-proline hydrochloride as shown in the formula (4), so that the problems that the preparation cost of the existing alpha-methyl-L-proline hydrochloride is relatively high and the yield is relatively low can be solved.

The invention relates to a suzertraline intermediate as well as a preparation method and application thereof, and particularly provides a suzertraline intermediate 3, 4-difluoro-2-methoxyphenylacetic acid compound and a preparation method thereof, and the suzertraline intermediate can be used for preparing 3, 4-difluoro-2-methoxyphenylacetic acid. Specifically, 2, 3, 4-trifluoronitrobenzene which is low in price and easy to obtain serves as a starting raw material, 3, 4-difluoro-2-methoxyphenylacetic acid is prepared through a substitution reaction, a methylation reaction, a reduction reaction, a Meerwein arylation reaction and a hydrolysis reaction, the method is mild in reaction condition, a reaction substrate better meets the economic and environment-friendly requirements, reaction operation and a post-treatment process are safe and simple, and the method is suitable for industrial production. The purification steps are simple and convenient, byproducts are few, a target product with high purity can be obtained conveniently, corrosion to equipment is small, special equipment is not needed, and the method is suitable for industrial production.

The invention belongs to the technical field of synthesis and preparation of high-molecular optical materials, and particularly relates to a multi-mercaptothiol composition as well as a preparation method and application thereof. According to the present invention, the three-step synthesis route of the tetrahydroxymethylation reaction, the thiol precursor introduction and the deprotection is adopted, the reaction conditions are mild, the steps are clear, the yield is high, the complexity of the traditional synthesis route is avoided, the production cost is reduced, and the industrial production is easily achieved. In the aspect of refractive index regulation and control, the compound contains a plurality of sulfur atoms, the coating is endowed with the characteristic of high refractive index, accurate regulation of the refractive index can be realized by adjusting the formula of the composition, the requirements of different optical applications are met, and the application range of the material is widened. The prepared optical coating has excellent light transmittance, light loss can be reduced to the maximum extent, and the efficient performance of an optical device is ensured; meanwhile, the haze value of the coating is low, the light scattering phenomenon is effectively avoided, and the imaging definition and the precision of an optical system are guaranteed.

The invention relates to the technical field of covalent organic framework functional materials, in particular to a pyridine-rich imine type covalent organic framework as well as a preparation method and application thereof. The pyridine-rich imine type covalent organic framework disclosed by the invention has a structure as shown in the following formula (I): # imgabs0 # formula (I). The pyridine-enriched imine type covalent organic framework disclosed by the invention contains rich pyridine-N active sites, can efficiently adsorb iodine through Lewis acid-base action, and can effectively fix iodomethane through methylation reaction, so that two iodine pollutants can be efficiently captured at the same time. The pyridine-rich imine type covalent organic framework disclosed by the invention also has good crystallinity, larger specific surface area and excellent thermal stability and acid-base stability, and can realize efficient adsorption of iodine and iodomethane.

The invention provides a method for synthesizing N-methylated polypeptide, which comprises the following steps: dissolving a carboxylic acid compound, N-methyl amino-acid ester hydrochloride or N-methyl amino-acid ester, an alkaline substance and pivaloic anhydride in an organic solvent, reacting at 15-80 DEG C for 3-10 hours, and post-treating the obtained reaction liquid to obtain an N-methyl dipeptide compound, the method comprises the following steps: removing a protecting group in an N-methyl dipeptide compound to obtain a free-state N-methyl dipeptide compound, and condensing the free-state N-methyl dipeptide compound and amino acid or N-methyl amino-acid ester protected by amino to obtain the N-methylated polypeptide, the mixed anhydride intermediate is formed in situ, and the reaction is completed in one step; according to the method, trimethylacetic anhydride is used as a condensing agent, the structure is simple, the reaction is safe, cheap and non-toxic, a large amount of nitrogen-containing byproducts are not generated in the reaction, and purification is convenient; the method is high in stereoselectivity, and racemization is avoided; according to the method, environment-friendly solvents such as ethyl acetate can be used, the reaction condition is mild, and the reaction time is short.

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 invention provides a preparation method of (S)-(+)-1-methoxy-2-propylamine hydrochloride, which comprises the following steps: taking (S)-(+)-2-amino-1-propanol as a raw material, carrying out halogenation reaction and amino protection, then carrying out methylation reaction with methanol, and finally carrying out amino deprotection by using hydrochloric acid to obtain the product (S)-(+)-1-methoxy-2-propylamine hydrochloride. The method is suitable for industrial production.

The present invention relates to the field of organic chemical synthesis, and specifically relates to a 6-bromonicotine synthesis method. The 6-bromonicotine synthesis method uses 6-hydroxymyosmine (CAS: 70969-38-9) as a starting material, which sequentially undergoes a reduction reaction, an amine methylation reaction and a bromination reaction, to finally obtain the target product 6-bromonicotine. The product purity of the 6-bromonicotine obtained by means of the synthetic route can reach 99.0% or more. The present synthesis method has a simple process and a high yield, and is suitable for industrial scale-up production.

The present invention discloses a polyporus badius polysaccharide and its preparation method and application, belonging to the technical field of polysaccharide extraction. The polyporus badius polysaccharide (PPP-0A) includes galactose, fucose, glucose, mannose and xylose, and the molar ratios are 62.26%, 16.96%, 15.23%, 4.68% and 0.87% respectively. The present invention uses techniques such as methylation, scanning electron microscopy, thermogravimetric analysis, nuclear magnetic resonance and atomic force microscopy to determine the structural characteristics of PPP-0A, analyze its composition and properties, and its inhibitory effects on the activities of α-glucosidase and α-amylase. In addition, an in vitro HepG2 cell model induced by high blood glucose and high insulin levels was used to study the hypoglycemic effect of PPP-0A. The present invention provides a theoretical basis for clarifying the relationship between the hypoglycemic activity of PPP-0A and its hypoglycemic effect on type 2 diabetic mice.

The present invention provides a method for preparing an α-cadaverine-based compound of the following general formula (3): wherein R 2 represents a monovalent hydrocarbon group having 1 to 9 carbon atoms, the method comprising: making a 3,5,5-trimethyl-3-cyclopentene compound of the following general formula (1): wherein R 2 As defined above, and X represents a leaving group, and the methylating agent of the following general formula (2): wherein M represents Li, Mg, Z 1 、ZnZ 1 、Cu、CuZ 1 or CuLiZ 1 , and Z 1 represents a halogen atom or a methyl group, undergoing a nucleophilic substitution reaction to form an α-cadaverine-based compound (3). The present invention also provides a method for preparing a γ-cadaverine-based compound of the following general formula (4): wherein R 2 represents a monovalent hydrocarbon group having 1 to 9 carbon atoms, and the method comprises: subjecting the thus obtained α-cadaverine-based compound (3) to positional isomerization reaction at the double bond to form a γ-cadaverine-based compound (4). #imgabs0#

The invention relates to the technical field of cathode electrophoretic paint, and discloses an asymmetric double-blocked isocyanate curing agent as well as a preparation method and application thereof. Based on the reaction activity difference of primary carbon and secondary carbon NCO groups in isophorone diisocyanate molecules, a step-by-step asymmetric sealing strategy is adopted: in the first stage, a hydrophilic chain extender containing a tertiary amine structure is utilized to preferentially react with high-activity primary carbon NCO, and an internal catalytic center and a hydrophilic group are anchored in a molecular skeleton; and in the second stage, the active methylene compound and the bio-based long-chain phenol are used for carrying out hybrid dual-sealing on the residual secondary carbon NCO with relatively large steric hindrance. According to the preparation of the curing agent, the curing agent integrates internal catalysis, stepped curing and self-emulsifying functions, the deblocking energy barrier is effectively reduced, and 140-DEG C low-temperature curing or high-temperature high-performance curing can be realized under the tin-free catalysis condition.

The invention provides a synthesis method of 1-methyl-L-histidine, which comprises the following steps: firstly, carrying out methylation reaction on a compound 1 and N, N-dimethylformamide dimethyl acetal to obtain a compound 3; the compound 3 and NCS are subjected to a chlorination reaction, and a compound 4 is obtained; then reacting the compound 4 with diethyl acetamidomalonate to obtain a compound 5; then carrying out hydrolysis decarboxylation on the compound 5 to obtain a compound 6; and finally, splitting the compound 6 by using acetyl hydrolase to obtain a chiral compound 7 (namely 1-methyl-L-histidine). The synthesis route is short, the raw materials are cheap, the production cost can be reduced, the product yield and purity are high, and large-scale industrial production is facilitated.

The invention relates to the technical field of biological medicine, in particular to a novel amino acid or polypeptide side chain carbonylation modification reagent which can be used as a novel carbonylation reagent in a method for synthesizing gamma-C (sp3)-H bond carbonylation amino acid or polypeptide through palladium catalysis. Substituting ethylene with a novel carbonylation reagent 1-iodine-2-bromine under the action of a palladium catalyst, an additive and a solvent to realize carbonylation and methylation of the amino acid gamma-C (sp3)-H bond. The method disclosed by the invention has the beneficial effects that a novel carbonylation reagent easy to prepare is developed, substrate raw materials are easy to obtain, the operation is simple and convenient, the condition is mild, the substrate application range is wide, and a plurality of carbonylated amino acids and polypeptide derivatives can be efficiently and accurately synthesized at low cost; and a novel method is provided for modification of unnatural amino acids and polypeptide side chains.

The invention belongs to the field of electrochemical synthesis, and particularly discloses a method for synthesizing N, N, N ', N'-tetramethyl methylenediamine by directly utilizing a dimethylamine aqueous solution through electrochemical amine methylenation. According to the method, a dimethylamine aqueous solution is used as a raw material, and an electrochemical amine methyleneation reaction of dimethylamine is carried out on an anode loaded with a carbon material catalyst in an electrically driven oxidation manner, so that synthesis of N, N, N ', N'-tetramethyl methylenediamine is realized. Different from the existing dimethylamine and formaldehyde condensation method and dimethylamine and methanol electrosynthesis method, the method disclosed by the invention directly adopts the industrial dimethylamine aqueous solution as a raw material to synthesize N, N, N ', N'-tetramethyl methylenediamine, so that the process flow is simplified, and the yield is high. The method has the characteristics of mild process conditions, high system stability, few byproducts, greenness, safety, low cost and suitability for industrial application. The method has wide application potential in the fields of electrochemical organic synthesis, energy storage, pharmaceutical chemical industry and the like.

The invention discloses a liver tissue regeneration regulation and control method based on epigenetic state regulation and control, and relates to the technical field of biology. Comprising the following steps: sampling the liver tissue at a plurality of preset time points after the liver tissue is damaged or partially resected, selecting a target gene related to liver tissue regeneration regulation, and detecting an epigenetic state of a promoter region of the target gene; comparing and analyzing the change of the epigenetic state of the target gene promoter region on the basis of detection results obtained at different time points, and determining epigenetic modification characteristics in the liver tissue regeneration process; according to an analysis result, intervening the expression level of a regulatory factor related to DNA methylation or DNA hydroxymethylation so as to regulate the epigenetic state of the target gene promoter region; after intervention is completed, the transcription expression condition of a target gene and the activity change of a cell signal channel related to liver tissue regeneration are detected, and the liver tissue regeneration process can be effectively regulated and controlled through the method.

The invention relates to a method for producing mecobalamin by using a micro-channel reactor, which comprises the following steps: firstly, introducing a reaction mixed solution of cyanocobalamin, cobalt chloride, sodium borohydride and purified water into a first micro-channel reactor for reduction reaction; the obtained cyanocobalamin solution in the reduction state is introduced into a second microchannel reactor to be subjected to a methylation reaction with a trimethylsulfoxide iodide solution, and finally, an obtained mecobalamin solution is subjected to post-treatment to obtain a finished product. Compared with the prior art, the micro-channel reactor is used for continuous production, the mass and heat transfer effect is good, the reaction temperature can be accurately controlled, side reactions are further reduced, and the product quality is effectively improved.

The invention discloses an alpha-dideuterium methylated sulfone compound as well as a synthesis method and application thereof, and belongs to the field of organic chemistry. In an air atmosphere, benzyl methyl sulfone and 2-((3, 5-dimethyl-4-methoxypyridine-2-yl) methylsulfonyl)-5-methoxy-1H-benzo [d] imidazole are used as substrates, in the presence of a catalyst [Cp * IrCl2] 2 and cesium carbonate, deuterated paraformaldehyde is used as a carbon source, sodium formate is used as an additive, and the alpha-dideuterium methylated sulfone compound is obtained through a reaction in an acetonitrile solvent at 120 DEG C. The reaction does not need to use a ligand and hydrogen, the reaction is simple and efficient, the potential value of the compound in medicinal chemistry is shown, and the compound has a certain inhibition effect on H3N2 subtype influenza viruses and has remarkable application potential.

The invention discloses a preparation method of an azacyclo-bis (fluorosulfonyl) imide salt derivative, which comprises the following steps of: 1, mixing an azacyclo-compound, a methylation reagent, an ethylation reagent, bis (fluorosulfonyl) imide salt and inorganic alkali in a polar organic solvent, heating, and filtering after complete reaction to obtain crude filtrate containing the azacyclo-bis (fluorosulfonyl) imide salt; the nitrogen heterocyclic compound is selected from one of oxazolidine, 4-cyano piperidine, 4-fluoro piperidine, 4, 4-difluoro piperidine and 3-cyano piperidine; the bis (fluorosulfonyl) imide salt is selected from one of lithium bis (fluorosulfonyl) imide and potassium bis (fluorosulfonyl) imide; and 2, adding an inert organic solvent into the crude product filtrate for crystallization, and performing vacuum drying to obtain a finished product. The method has the advantages that the operation steps are few, the synthesis efficiency is greatly high, the process is greatly simplified, and the preparation cost is effectively reduced.

The invention provides an aminomethylation reaction method based on a pyrazolo [1, 5-a] pyrimidine nitrogen-containing fused heterocycle substrate, a product and application, and belongs to the technical field of chemistry. Pyrazolo [1, 5-a] pyrimidine nitrogen-containing fused heterocycle, secondary amine and glyoxylic acid are used as raw materials, an aminomethylation reaction is achieved at the C3 site of pyrazolo [1, 5-a] pyrimidine through heating for the first time, a transition metal catalyst or a chemical oxidizing agent is not needed, the drug purification problem caused by metal residues and oxidation byproduct pollution are avoided, and the purity of the product is improved. The method is a novel efficient, simple, convenient and environment-friendly nitrogen-containing fused heterocyclic aromatic hydrocarbon functionalization strategy, the reaction can be directly carried out at the temperature of 100-120 DEG C, shielding gas does not need to be filled, and compared with some reactions needing high-temperature or high-pressure conditions, the mild reaction conditions are easier to control, side reactions are reduced, and the yield of the target product is increased. Meanwhile, the reaction conditions are also beneficial to reducing energy consumption, and conform to the concept of green chemistry.

The invention discloses p-toluenesulfonic acid 8-tert-butyl diphenyl silyloxy-7-methyl octyl ester as well as a synthesis method and application thereof, and relates to the technical field of biopesticides. The preparation method comprises the following steps: taking 8-bromocaprylic acid as an initial raw material, and firstly reacting with t-BuOK and 18-crown ether-6; then reacting with pivaloyl chloride to generate acid anhydride, and then carrying out acylation reaction with 4-benzyl oxazolidine-2-ketone; then carrying out diastereoselective methylation; then, NaBH4 reduction is carried out; carrying out hydroxyl protection; then carrying out hydroboration oxidation reaction; and then carrying out TsCl sulfonylation, so as to synthesize the p-toluenesulfonic acid-8-tert-butyl diphenyl silyloxy 7-methyl octyl ester. The optical purity of the (S)-p-toluenesulfonic acid 8-tert-butyl diphenyl silyloxy-7-methyl octyl ester synthesized in the invention reaches 98%, and the optical purity of the (R)-p-toluenesulfonic acid 8-tert-butyl diphenyl silyloxy-7-methyl octyl ester synthesized in the invention also reaches 98%.

A preparation method of the methacrylated gelatin with the dual functions comprises the following steps: firstly, preparing collagen methylated polymethacrylate, then mixing 5% of collagen methylated polymethacrylate, 0.2% of trimethylbenzoyl phosphonate, 10 mg / ml of a herba houttuyniae extract and 20 micrograms / ml of nifedimab, and carrying out uniform mixing, so as to obtain the methacrylated gelatin with the dual functions, the collagen methylated polymethacrylate and the trimethylbenzoyl phosphonate, the herba houttuyniae extract, the nifedimab and the collagen methylated polymethacrylate, the herba houttuyniae extract and the nifedimab. The methacrylated gelatin is prepared under ultraviolet irradiation, and the loose cross-linked network structure of the methacrylated gelatin can realize continuous release of drugs, so that the demand of continuous and stable drug delivery is met; in addition, the gelatin methacrylamide, the herba houttuyniae extract and the nintedanib are combined to relieve hemorrhagic intestinal adhesion and can regulate inflammation and anti-fibrosis functions.

The present invention discloses a methylated amino resin and its synthesis method, belonging to the technical field of amino resin preparation, and comprising the following steps: adding methanol to the hydroxymethylated intermediate product, adjusting the pH to 3 - 4.2 with acid, controlling the temperature at 60 - 65 °C, carrying out a heat preservation reaction for 3 - 4 h, then adjusting the pH to 8.8 - 9 with alkali, raising the temperature to 110 - 115 °C for distilling off water, cooling to 45 - 50 °C and adding auxiliary components, then raising the temperature to 85 °C for a constant temperature reaction for 3 - 4 h, after cooling to room temperature, standing for 4 - 6 h and then filtering, heating the filtrate under normal pressure for distillation for 1 - 2 h, then starting the vacuum system, with a vacuum degree of -0.085 MPa, carrying out heat preservation treatment at 70 °C for 3.5 - 4 h, pumping the product into the finished product kettle, adding isobutanol, and stirring evenly to obtain the methylated amino resin. Compared with the existing methylated amino resin, the content of free formaldehyde is lower, and the paint film formed after crosslinking has good toughness and good water resistance.

The invention particularly relates to 4 '-thiosugar and a preparation method thereof. The preparation method comprises the following steps: taking D-ribose as a raw material, firstly carrying out methylation protection on C1-site hydroxyl, and then carrying out benzylation protection on other hydroxyl; the preparation method comprises the following steps: firstly, carrying out hydrolysis on a glucosidic bond at a C1 site, carrying out reduction through hydroboron to obtain open-loop ribitol (formula V), carrying out sulfonic acid esterification and bromination substitution on hydroxyl of the ribitol, forming a sulfur bridge bond by taking sodium sulfide as a nucleophilic reagent to obtain benzyl-protected thiosugar, oxidizing a thioether bond into sulfoxide, rearranging to obtain acetoxy thioether, and carrying out debenzylation reaction and hydroxybenzoylation reaction to obtain the high-purity acetoxy thioether. According to the present invention, the multi-step intermediate reaction only needs simple purification, the key intermediate can be obtained through recrystallization, the method is simple, the yield is high, the amplification production is convenient, and the obtained 4 '-thiosugar as the basic sugar can participate in the reaction with a variety of basic groups to form the sulfur-containing nucleoside so as to provide the good foundation for the subsequent drug development or activity screening.

The invention belongs to the technical field of organic synthesis, and discloses ketoxime ether as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing a ketoxime compound, tert-butyl alcohol and alkali to obtain a mixed solution; and adding a methylation reagent into the mixed solution, and reacting to obtain ketoxime ether. The preparation method is low in raw material cost and simple in process operation; tert-butyl alcohol is used as a solvent, sodium tert-butoxide is used as an alkali source, no water participates in the reaction process, ketoxime hydrolysis is effectively reduced, side reactions are greatly reduced, the yield of the obtained product is high, and subsequent separation and solvent recycling are facilitated; use of toxic substances such as sulfur dioxide and sodium nitrite is avoided, and emission of toxic gases such as nitrogen oxides is reduced; and the process safety risk is reduced, and the method is safe, reliable, simple and feasible.

The invention discloses a preparation method of N-methyl o-fluoroaniline, which is characterized in that o-fluoroaniline is used as a starting raw material, and a target product is efficiently synthesized through three steps of reaction: step 1, in the presence of a solvent and alkali, o-fluoroaniline and acetyl chloride are acetylated at low temperature to generate 2-fluoro-acetanilide, and the product is directly used for the next step after being roughly purified; 2, under the action of a solvent and alkali, carrying out controllable methylation on the 2-fluorine-acetanilide and dimethyl carbonate to obtain 2-fluorine-N-methylacetanilide; and 3, removing acetyl protection through acidic hydrolysis, and adding sodium thiosulfate to prevent oxidation to finally obtain a high-purity product. According to the method, excessive methylation is avoided through an acetyl protection strategy, the process does not need high-risk operations such as ultralow temperature and high pressure, the operation is simple and convenient, the energy consumption is low, and the product purity is gt; the total yield reaches 79.86%, and the method is green, safe and suitable for industrial production.

The invention relates to the technical field of organic synthesis, and provides a synthesis method of an important organic synthesis intermediate methyl diethyl phosphonate. Comprising the following steps: firstly, adding paraformaldehyde and alkali into a solvent, heating and stirring, and filtering to obtain an intermediate solution; and adding cation exchange resin and the intermediate solution into a reaction flask, dropwise adding diethyl phosphite, carrying out a heat preservation reaction after dropwise adding is completed, filtering to remove the cation exchange resin (which can be recycled for multiple times) after the reaction is completed, and carrying out reduced pressure distillation to remove the solvent and a trace amount of diethyl phosphite residue, so as to obtain the product. The method has the main advantage that paraformaldehyde is used as a methylation reagent and reacts with diethyl phosphite in one step under the action of a catalyst to obtain a target product.