33 results about "Ethylmalonic acid" patented technology

The invention provides a new technology for preparing 5,5-diethyl-barbituric acid compound, which comprises steps as follows: malonic ester reacts with bromoethane under the condition of 'boiling in one pot' while alcobolic solution of sodium alcoholate exists to obtain 5,5- diethyl-malonic ester; the bromoethane reacts with urea while the alcobolic solution of sodium alcoholate exists; the reaction is completed in a concentration process; after the concentration is finished, water or (mother solution) is added for dissolution and acidification is carried out to obtain crude 5,5-diethyl-barbituric acid; water or ethanol water is recrystallized to prepare 5- ethyl-5-isopentyl balbituric acid compound. The technology is stable and carbethoxy and diethyl ester are completed under the condition of 'boiling in one pot'; the synthesis reaction with the urea is completed during distillation process; the technology has no particular requirement on the concentration of sodium alcoholate and has the advantages of easily controllable reaction conditions, short reaction time, simple operation, less three wastes, good product quality, high yield, low production cost and being more applicable to industrialized production.

The invention relates to a method for purifying phenyl ethyl malonate, comprising the following steps: dissolving coarse phenyl ethyl malonate into a nonpolar solvent; decoloring by active carbon; filtering; mixing and crystallizing at the temperature of -10 DEG C to -5 DEG C; filtering to obtain a first filter cake; decompressing and recovering the solvent by the first filter cake to obtain colorless oil liquid as a fine product; dissolving the fine product into the nonpolar solvent; stirring and crystallizing at the temperature of -10 DEG C to -5 DEG C; filtering to obtain a second filter cake; decompressing the second cake to recover the solvent; and obtaining colorless transparent liquid as a phenyl ethyl malonate pure product. The purity of the phenyl ethyl malonate is greater than or equal to 99.5 percent, 2-phenyl-2-ethyl malonate impurities are less than 0.1 percent, and the total yield is greater than 90.0 percent.

A process for preparation of diethyl 2-aetamido-2-(4-octyl phenyl)ethyl malonate (III), a key intermediate of fingolimod hydrochloride comprising reaction of 2-(4-octylphenyl)ethyl iodide (IV) with diethyl acetamido malonate in presence of a base and an iodinating agent and in an organic solvent. The compound of formula (III) thus obtained provided fingolimod hydrochloride (Ia) having associated impurities below the regulatory limits.

The invention discloses a method for preparing vinpocetine intermediate gamma-hydroxypropyl-ethylmalonic acid, and belongs to the chemical industry synthesis field. The preparation method comprises the following steps: 1, adding sodium hydride into an organic solvent, adding 2-ethyl diethylmalonate and 1-bromo-3-chloropropane, extracting by using ethyl acetate, and carrying out reduced pressure concentration of a solvent to obtain gamma-chloropropyl-ethyl diethylmalonate; and 2, adding gamma-chloropropyl-ethyl diethylmalonate to an ethanol-water solvent of sodium hydroxide, refluxing, adding a proper amount of water, adjusting the pH value to 1 by using concentrated hydrochloric acid, crystallizing, and carrying out pumping filtration to obtain a white solid gamma-hydroxypropyl-ethylmalonic acid, wherein a molar ratio of 2-ethyl diethylmalonate to 1-bromo-3-chloropropane to sodium hydride in step 1 is 1:1-1.2:1-1.3; and a reaction temperature in the step 1 is 10-40DEG C, and a reaction time of 1-bromo-3-chloropropane, 2-ethyl diethylmalonate and 1-bromo-3-chloropropane is 8-15h. The intermediate is gamma-hydroxypropyl-ethylmalonic acid, and the preparation method has the advantages of cheap and easily available raw materials, low cost, short reaction steps, simple operation, good product quality, and benefit for protecting the green resource.

he invention provides a synthetic method for an intermediate, i.e., diethyl diethylmalonate, of barbiturate. The synthetic method comprises the following steps: adding 1.13 mol of ethanolamine and 0.5 mol of cuprous chloride into a reaction vessel and controlling a stirring speed to be 130 to 160 rpm; after complete dissolving of ethanolamine, adding 0.65 mol of diethyl malonate drop by drop within 2 to 3 h; heating a solution obtained in the previous step to 70 to 75 DEG C and maintaining the heating state for 50 to 70 min; carrying out cooling, wherein a solid is precipitated; then adding 1.1 to 1.3 mol of ethylamine drop by drop within 2 to 3 h and maintaining a reflux state for 4 to 5 h; adding 300 ml of a potassium chloride solution and decreasing the temperature of the solution to 5 to 8 DEG C; carrying out extraction with cyclohexane three to five times and combining extract; successively carrying out washing with a salt solution, dehydrating with a dehydrating agent and evaporation of cyclohexane; then carrying out pressure-reduced distillation and collecting a fraction obtained at a temperature of 185 to 195 DEG C; and subjecting the fraction to re-crystallization in acetonitrile so as to obtain a crystal, i.e., diethyl diethylmalonate; wherein the mass fraction of the potassium chloride solution is 15 to 20%, the mass fraction of cyclohexane is 80 to 85%, and the salt solution is any one selected from a group consisting of sodium nitrate and potassium sulfate.

Provided is a process for producing 3,5-dimethyldodecanoic acid, which is an active ingredient of the pheromone of California prionus. More specifically provided is a method for producing 3,5-dimethyldodecanoic acid (5) comprising the steps of converting 2-methylnonyl halide (1) to a 2-methylnonyl metal reagent (2), and reacting the 2-methylnonyl metal reagent (2) with 2-ethylidene malonic acid ester (3) to form 2-(1,3-dimethyldecyl)malonic acid ester (4) as a result of 1,4-addition of the 2-methylnonyl metal reagent (2) to the 2-ethylidene malonic acid ester (3), as shown in the following scheme:

The invention discloses a preparation method of diethyl ethylisopentylmalonate. The preparation method comprises following steps: 1), ethanol and sodium react to generate sodium ethoxide; 2), diethyl ethylmalonate is added to sodium ethoxide obtained in the step 1), and diethyl ethylmalonate sodium salt is generated; 3), 1-bromo-3-methylbutane is added to the diethyl ethylmalonate sodium salt obtained in the step 2), and diethyl ethylisopentylmalonate is generated after reaction. Diethyl ethylisopentylmalonate is prepared from ethanol, sodium, diethyl ethylmalonate and 1-bromo-3-methylbutane as the raw materials, and prepared diethyl ethylisopentylmalonate has high yield and high purity and meets the drug quality standard.

Provided is a process for producing 3,5-dimethyldodecanoic acid, which is an active ingredient of the pheromone of California prionus. More specifically provided is a method for producing 3,5-dimethyldodecanoic acid (5) comprising the steps of converting 2-methylnonyl halide (1) to a 2-methylnonyl metal reagent (2), and reacting the 2-methylnonyl metal reagent (2) with 2-ethylidene malonic acid ester (3) to form 2-(1,3-dimethyldecyl)malonic acid ester (4) as a result of 1,4-addition of the 2-methylnonyl metal reagent (2) to the 2-ethylidene malonic acid ester (3), as shown in the following scheme:

The invention discloses a method for preparing high-quality mercaptoacetic acid from a tail solution from O-alkyl-N-alkyl thinocarbamate production. The method comprises the following steps: (1) performing acidizing treatment on the tail solution by using an inorganic acid, and controlling the pH value to be 0.5-1.5; (2) leaving to stand for 6-48 hours, separating suspended organic matters, extracting by using an organic solvent, and extracting by using an extraction agent, thereby obtaining an extraction liquid, wherein the volume ratio of the total amount of the organic solvent to an acidifying liquid is (2.5:0.01)-(2.5:0.1), the organic solvent consists of 40-60wt% of glutaric acid diethyl ester and 40-060wt% of ethyl malonic acid diethyl ester, the volume ratio of the total amount of the extracting agent to a new acidifying liquid is (2:0.1)-(2:2), and the extracting agent is prepared by mixing n-amyl ether, isoamyl ether and sec-butyl methyl ether in a mass ratio of (1-3):(1-3):(1-3); (3) removing the solvent and water from the extraction liquid, thereby obtaining crude acid; (4) performing flash evaporation on the crude acid. The method is high in recycling rate, high in product purity, good in quality and simple in process.

The invention discloses a method for synthesizing remote fluorinated aryl olefins, belonging to the field of organic chemistry. Taking 2-allyl-2-diethyl phenethylmalonate and its derivatives as raw materials, and reacting in the presence of phosphorus ligands, inorganic bases and organic solvents, the fluoroolefin compound three of the present invention is obtained. Ethyl (E)-1,1-difluoro-7-phenylhept-6-ene-1,5,5-tricarboxylic acid. The method of the invention can be completed in one step by palladium catalysis, and at the same time of isomerizing the olefin, difluoroalkylation is realized, which provides a direct and effective way for the synthesis of such compounds.

The invention provides a preparation method of 2-oxo-3-ethyl piperidinecarboxylate. The preparation method comprises the following steps: S1, mixing diethyl malonate and a base catalyst uniformly, andthen dropwise adding acrylonitrile at 10 to 50 DEG C for reaction to obtain diethyl 2-(2-cyanoethyl)malonate; S2, reacting 2-(2-cyanoethyl)malonate, an organic solvent and a Raney cobalt catalyst at75-130 DEG C in a hydrogen atmosphere, and carrying out recrystallization to obtain 2-oxo-3-ethyl piperidinecarboxylate. Compared with the prior art, the preparation method has the beneficial effectsthat the raw materials are easily available, the operation is simple, and the total yield reaches 77% or higher compared with a classic N.F.Albertsm method (which is improved by 20%), so that the preparation method is very suitable for industrial production.

A highly active supported chromium catalyst composition for ethylene and other olefins polymerization and also for ethylene copolymerization with efficient incorporation of comonomer, produces polymers with superior spherical morphology, improved bulk density and almost 0% fines. The catalyst composition component includes at least one chromium compound, mainly chromium acetylacetonate, or chromium hexaflouroacetonylacetonate, or chromium diethylmalonate. One magnesium compound, or aluminum compound, metal alkoxy compound and defined polymer particles mainly chloromethylated cross linked styrene-DVB copolymer or polyvinylchloride. The catalyst composition, when used in conjunction with an organoaluminum compound or a mixture of organoaluminum compounds, can be used for olefin polymerization to produce medium or high density polyethylene and copolymers of ethylene with alpha-olefins having about 3 to 18 carbon atoms.

The invention belongs to the technical field of medicine synthesis, and relates to a preparation method of a ketorolac tromethamine intermediate. According to the preparation method, 2, 5-dimethoxy tetrahydrofuran reacts with a compound 2-(2-aminoethyl) diethyl malonate to generate the important intermediate 2-(2-(1H-pyrrole-1-yl) ethyl) diethyl malonate of ketorolac tromethamine. According to the novel method for synthesizing the ketorolac intermediate, use of dangerous chemical reagents is avoided, the synthesized intermediate does not generate new impurities, a traditional catalyst is replaced with a green catalyst, the reaction is milder, economical and environmentally friendly, the yield is high, and the method is suitable for industrial production.

The invention relates to a synthesis method of a barbitone drug intermediate diethyl diethylmalonate, which comprises the following steps: adding 1.13 mol of ethanolamine and 0.5 mol of cuprous chloride into a reaction vessel, controlling the stirring rate at 130-160 rpm until the ethanolamine is completely dissolved, dropwisely adding 0.65 mol of diethyl malonate within 2-3 hours, heating the solution to 70-75 DEG C, keeping the heating state for 50-70 minutes, cooling to precipitate a solid, dropwisely adding 1.1-1.3 mol of ethylamine within 2-3 hours, keeping the reflux state for 4-5 hours, adding 300ml of potassium chloride solution, cooling the solution to 5-8 DEG C, extracting with cyclohexane 3-5 times, merging the extracting solutions, washing with a salt solution, dehydrating with a dehydrating agent, distilling to remove the cyclohexane, distilling under reduced pressure, collecting the 185-195-DEG C fraction, and recrystallizing in acetonitrile to obtain the crystal diethyl diethylmalonate, wherein the mass percent of the potassium chloride solution is 15-20%, the mass percent of the cyclohexane is 80-85%, and the salt solution is any one of sodium nitrate and potassium sulfate.

The invention relates to a synthetic method of 2,2-bis (trifluoroethyl) propanol and mainly solves the technical problem that the existing synthetic method is lack of industrialization prospect. The method includes subjecting dibenzyl ester malonate and trifluoroethyl triflate to a step-by-step reaction in the presence of an alkalization agent to obtain 2,2-bis (trifluoroethyl) dibenzyl ester malonate 2; reducing the composition 2 through lithium aluminum hydride to obtain 2,2-bis (trifluoroethyl)-1,3-propylene glycol; and using tosyl to protect one hydroxyl and then using sodium borohydride for reduction to obtain the 2,2-bis (trifluoroethyl) propanol. The 2,2-bis (trifluoroethyl) propanol can be prepared quickly and conveniently through the method.