88 results about "Methyl malonate" patented technology

The invention provides a post-treatment method for 4,6-dihydroxypyrimidine synthesis, belongs to the technical field of organic chemical industry, and relates to a method for alkali recovery and application and wastewater recovery and application in a chemical industry product, particularly to a process. According to the process, formamide, dimethyl malonate and sodium methoxide are adopted as starting raw materials and cyclization is performed to prepare 4,6-dihydroxypyrimidine; after the reaction is completed, negative pressure suction filtration is performed, the filtrate is subjected to partial methanol removing, and the alkali is recovered and applied; and after the filter cake is subjected to acidification crystallization, negative pressure suction filtration is performed, the filter cake is dried to obtain the product, the mother liquor is concentrated to recover the 4,6-dihydroxypyrimidine, and the acid water is neutralized so as to be recycled while the by-product salt can be recovered so as to be comprehensively utilized. According to the present invention, after the alkali recovery and application, the acid consumption for the subsequent acidification treatment can be significantly reduced so as to substantially reduce the production cost and the three-waste amount; and the post-treatment method has characteristics of less equipment investment, three-waste treatment cost reducing, easy raw material recovery and application, and the like, and is suitable for industrial production.

The invention provides a preparation method of sitagliptin. The preparation method comprises the following steps of: performing condensation reaction on hydrochloride of 3-trifluoromethyl-[1,2,4] triazol [4,3-a] piperazine serving as a starting raw material and methyl malonyl chloride under a normal temperature condition; reacting an obtained product with 2,4,5-trifluorophenylacetic acid under an alkaline condition and then performing condensation reaction with (S)-phenylglycinamide under normal temperature condition to obtain a product; reducing the obtained product through a reducing agent; removing an ester group through heating reflux; and reacting with a hydrogenation reducing reagent to obtain the sitagliptin. The preparation method has the advantages of low cost, high yield, easiness in operation, all used reagents of conventional reagents, simple post-treatment and convenience for industrial production.

The present invention proposes a method for synthesizing clethodim, comprising 3,5-heptadiene-2-one (formula II) and ethanethiol for nucleophilic addition to prepare clethodim intermediate 6-ethylthio ‑3‑heptene‑2‑ketone (formula III); formula III reacts with dimethyl malonate and propionyl chloride to prepare (±)‑3‑[propionyloxy]‑5‑[ 2-(Ethylthio)propyl]-6-[methoxyformyl]cyclohex-2-enone (Formula V); Formula V is then rearranged, hydrolyzed and decarboxylated to obtain (±)-2- [Propionyl]-3-[hydroxyl]-5-[2-(ethylthio) propyl]cyclohex-2-enone (formula VIII); formula VIII reacts with chloroallyloxyamine to obtain alkene Clethodim (formula I), the method for preparing clethodim by using intermediate 3,5-heptadiene-2-one (formula II) in the present invention is proposed for the first time, and the clethodim (formula I) prepared by this method is generally The yield is high, the product quality is good, and the method has low production cost and little environmental pollution, and is suitable for large-scale production.

The invention provides a preparation method of 6-chloro-1,3-dimethyluracil, which comprises the following steps: carry out reflux reaction on 1,3-dimethylbarbituric acid and a chlorinating agent in a water-insoluble organic solvent to obtain a reaction mixture; and adding water to quench the reaction to obtain the 6-chloro-1,3-dimethyluracil, wherein the chlorinating agent comprises phosphorus oxychloride. The preparation method provided by the invention reduces the consumption of phosphorus oxychloride, and does not need to perform vacuum distillation on the phosphorus oxychloride. Furthermore, additives can be added in the reaction process to enhance the yield of the 6-chloro-1,3-dimethyluracil. The invention also provides a method for synthesizing 1,3-dimethylbarbituric acid, which is implemented by reacting 1,3-dimethylurea, dimethyl malonate and a condensing agent in an organic solvent. The method avoids using abundant malonic acid and acetic anhydride.

The invention discloses a method for synthesizing p-toluenesulfonic acid-catalyzed dimethyl malonate. Chloroacetic acid is taken as a raw material, dimethyl malonate is generated through a neutralization reaction, a cyanation reaction, an acidification reaction, a hydrolysis reaction and an esterification reaction, the esterification reaction is performed under the catalytic effect of p-toluenesulfonic acid, a catalyst is recovered after the reactions, and the recovered catalyst can be recycled, so that the usage amount of the catalyst can be greatly reduced and sulfuric acid-containing wastewater cannot be produced by selecting p-toluenesulfonic acid instead of sulfuric acid in a traditional process as the catalyst in the esterification reaction; meanwhile, dichloroethane is added in the esterification reaction, has a good dissolving property for dimethyl malonate, is easily separated from dimethyl malonate through rectification and forms a ternary azeotropic system along with methanol and water, and the water generated in the reactions is continuously discharged from the system through azeotropy, so that the esterification reaction can be more thoroughly produced.

The invention discloses a sewage filter material and a preparation method of the sewage filter material. The sewage filter material comprises, by weight, 7-11 parts of styrene sulfonic acid, 20-30 parts of silica gel, 8-20 parts of polyacrylamide, 5-8 parts of dimethyl malonate, 7-14 parts of azodicarbonamide, 10-18 parts of nano-modified activated carbon, 10-15 parts of zeolite, 5-8 parts of straw fibers, 2-6 parts of alum and 0.8-2.0 parts of sepiolite. According to the preparation method of the nanometer modified active carbon, bamboo charcoal and titanium dioxide are mixed for modification, then polyepichlorohydrin and ethyl acetate are added, and the nanometer modified active carbon is obtained after stirring and drying. By the adoption of the sewage filter material and the preparation method, the physicochemical indexes of seriously-contaminated sewage are made to reach the GB18918-2002 standard; and the treatment process is simple, the dosage is small, the treatment effect is good, the performance is stable, the cleaning degree of the contaminated sewage is high, the cost of the treatment agent can be reduced effectively, and the sewage filter material and the preparation method have the very good economic benefits and a wide range of social benefits.

The invention relates to methods for preparing sulfadoxine and an intermediate of the sulfadoxine. The method for preparing the sulfadoxine sequentially comprises the following steps of: (1), in the presence of sodium ethylate, reacting methyl methoxyacetate with excessive diethyl oxalate to generate 3-methoxyl-2-oxo-ethyl methyl succinate, decarbonylating the 3-methoxyl-2-oxo-ethyl methyl succinate to obtain 2-methoxyl-ethyl methyl malonate; (2) reacting the 2-methoxyl-ethyl methyl malonate with formamide to generate a cyclized compound; (3) reacting the cyclized compound with phosphorus oxychloride to generate chloride; (4) performing condensation reaction; and (5) performing methyl oxidation reaction, wherein the purity of the 2-methoxyl-ethyl methyl malonate which is obtained in the step (1) is controlled to be more than or equal to 95 weight percent. By adoption of the methods, the purity of the 2-methoxyl-ethyl methyl malonate is effectively controlled to be more than 95 weight percent, the quality of the cyclized compound for cyclization reaction in next step can be improved, operation is simplified, and production cost is reduced.

The invention discloses a thermal-stimulated fluorescence/visible light color double-response capsule and a synthesis method thereof, and belongs to the technical field of chemical synthesis. Through specific molecular structure design, 4-dimethylamino salicylaldehyde and dimethyl malonate are subjected to grafting reaction to prepare chromophoric molecules with a plurality of unsaturated functional groups, the chromophoric molecules are mixed with a phase change material to realize optical double-response reversible output of solvent phase state regulation, and compared with a conventional three-component organic thermal response material, the product only needs two components, namely chromophoric body molecules and a phase change solvent, so that the preparation process is simplified, and the performance stability is high. After microcapsule coating, the material is free from influence of adverse environment, and the performance is stably maintained, so that long-term stable use is realized.

Disclosed is electronic grade malonic acid. The electronic grade malonic acid is obtained by hydrolyzing of dimethyl malonate and deionized water in the existence of a catalyst. The content of the dimethyl malonate and the deionized water is larger than 99.8%, the moisture content is smaller than 50PPM, the chloride content is smaller than 5PPM, the sulfate content is smaller than 5PPM, and the content of heavy metal ions is smaller than 5PPM. The technical problems that the yield of malonic acid in the prior art is low; and the quality on the aspects of purity, impurities, chloride, sulfate and heavy metal cannot meet the using requirement of the electronic industry are effectively solved.

The invention relates to a synthetic process of 1, 1-cyclopropane dicarboxylic acid dimethyl ester, and belongs to the technical field of pharmaceutical raw material intermediate synthesis. The synthetic process is characterized in that dimethyl malonate reacts with dibromoethane under the effect of a phase transfer catalyst under an alkaline condition, and thus 1, 1-cyclopropane dicarboxylic acid dimethyl ester is obtained. The preparation method has the advantages that the raw materials are easy to obtain, conditions are mild, technological operation and controllability are strong, the cost is low, and the yield is high.

The invention relates to a preparation method of 4-[(4,6-dihydroxyl-2-pyrimidinyl)amino] cyanobenzene. The method comprises the following steps: a, using an aqueous solution of para-cyanoaniline and mono cyanamide as a raw material, water or alcohol solvent as the single solvent or a mixed solvent of water and alcohol solvents as the reaction solvent, and hydrochloric acid as a catalyst to react so as to obtain an N-(4-cyanophenyl)guanidine hydrochloride; and b, using the N-(4-cyanophenyl)guanidine hydrochloride as the raw material, methanol as the reaction solvent, and sodium methoxide and dimethyl malonate as the reaction reagents to react so as to obtain the 4-[(4,6-dihydroxyl-2-pyrimidinyl)amino] cyanobenzene. The method is an improvement of the prior art and has the advantages of short reaction process, high production efficiency, high reaction yield, low cost, low impurity content, complete and stable reaction and the like.

The invention relates to the technical field of medicine synthesis, in particular to a novel synthesis method of a lobaplatin intermediate, the method comprises the following steps: taking low-toxicity dimethyl malonate as an initial raw material, carrying out coupling, bromination, cyclization, hydrolysis, amidation and dehydration reaction to synthesize high-purity trans-1, 2-dicyanocyclobutane. In the whole route synthesis, all adopted raw and auxiliary materials are easy to purchase, low in price and low in toxicity, the reaction conditions are not harsh and uncontrollable, the reaction conditions of each step can be suitable for amplified production, although the reaction steps are increased, the yield of the product is greatly improved, so that the cost is greatly reduced, and the purity of the obtained trans-1,2-dicyanocyclobutane is improved and completely meets the subsequent use requirements, and the market competitiveness is greatly improved.

The invention discloses a synthetic method of methyl dihydrojasmonate or an intermediate thereof, which comprises the following steps: under the action of a supported catalyst, carrying out Michael addition reaction on 2-pentylcyclopentenone and methyl acetate or dimethyl malonate to obtain the methyl dihydrojasmonate or the intermediate thereof, the supported catalyst comprises a carrier and an active component supported on the carrier; the active component is quaternary ammonium base, and the carrier is a modified molecular sieve; the modified molecular sieve is obtained by modifying a molecular sieve with propylene glycol methyl ether acetate. According to the synthesis method, a super-strong base or strong base catalyst which is extremely unstable and has harsh reaction conditions in the prior art is replaced, reaction steps are reduced, the reaction conditions tend to be mild, and the reaction safety is improved. The invention further discloses a catalyst used in the synthesis method.

The invention discloses a preparing method of 3-oxo-1-cyclobutane-carboxylic acid. The method comprises the following steps: 1, 3-dichloroacetone is adopted as the raw material to generate ketol reaction with ethylene glycol, then generate cyclization reaction with methyl malonate, or ethyl malonate or diisopropyl malonate, and finally generate hydrolysis reaction under strong acid condition to prepare the 3-oxo-1-cyclobutane-carboxylic acid. The method provides a brand new synthetic route, the reaction condition of each step is mild, the process is simple, the reactions in all the steps are normal operations, the raw materials with high cost are effectively avoided, the cost of the product is reduced, and the scale application of the product can be possible.

The invention discloses an m-hydroxy acetophenone preparation method which includes the steps: performing chlorination, dissolving m-hydroxybenzoic acid in methylbenzene, adding 4-dimethylamino pyridine serving as a catalyst, adding acyl thionyl chloride for chlorination to obtain m-hydroxybenzoic acid acyl chloride, and then removing the acyl thionyl chloride by concentration and evaporation to obtain m-hydroxybenzoic acid acyl chloride-methylbenzene solution; dissolving dimethyl malonate sodium salt in methylbenzene to obtain dimethyl malonate sodium salt-methylbenzene solution, dripping them-hydroxybenzoic acid acyl chloride-methylbenzene solution obtained in the step (1) into the dimethyl malonate sodium salt-methylbenzene solution, and then performing reflux reaction for 3-5 hours atthe reaction temperature of 50-80 DEG C to obtain a product A; adding the obtained product A into hydrochloric acid solution, and performing hydrolysis reaction to obtain m-hydroxy acetophenone. Thepreparation method is simple in process, small in wastewater discharge amount, low in cost and high in yield and final product purity.

The invention discloses an efficient glass product cleaning agent, which is prepared from the following raw materials in parts by weight: 3-5 parts of sodium tripolyphosphate, 1-3 parts of sodium hydroxide, 4-12 parts of isopropyl alcohol, 6-11 parts of dodecyl diphenyl ether sodium disulfonate, 4.5-6.5 parts of sodium silicate, 2.4-4.8 parts of ethanol, 12-24 parts of ammonium polyphosphate, 6-10 parts of acetone, 7-14 parts of stannous octoate, 15-25 parts of methyl malonate, 4-8 parts of a silane coupling agent, 8-14 parts of ferric oxide, 3-7 parts of succinic acid, 4-10 parts of fatty alcohol-polyoxyethylene ether, 3-5 parts of sodium hypochlorite and 2-7 parts of sodium chloride. The efficient glass product cleaning agent has the beneficial effects that the efficient glass product cleaning agent has an efficient cleaning function, and is short in cleaning time and convenient to operate; and the work efficiency is improved.

The invention discloses a preparation method of 2,4-dyhydroxyl-5-pyrimidinecarboxylic acid. The method comprises the following steps: with ethyl alcohol as a solvent, and methoxy methylene dimethyl malonate and urea as raw materials, adding sulfamic acid as a catalyst, heating, refluxing and carrying out condensation reaction, and distilling to remove an organic solvent; washing and drying to obtain a condensation product; carrying out a ring-closing reaction on the condensation product and a sodium hydroxide solution; and cooling to a room temperature, neutralizing excessive sodium hydroxide with hydrochloric acid, carrying out acidified hydrolysis, filtering, and washing with ice water for a plurality of times, so as to prepare a product 2,4-dyhydroxyl-5-pyrimidinecarboxylic acid. The preparation method disclosed by the invention has the characteristics of being simple in technological operation, cheap and available in raw material, mild in reaction condition, and simple in post-treatment; and the obtained yield can be accepted by industrialized production.