52 results about "2-Chloropropionic acid" patented technology

The invention discloses a synthesis method of R-(+)-2-(4-hydroxyphenoxy) propionic acid. The method comprises the following steps: (1), adding hydroquinone into a sodium hydroxide solution containingan organic solvent in batches, and performing reaction under in N2 atmosphere, so as to obtain p-hydroxy sodium phenate turbid liquid; (2), dissolving S-(-)-2-chloropropionic acid in an organic solvent, and slowly adding Na2CO3 solid in an ice-water bath condition to perform reaction, so as to obtain an S-(-)-2-sodium chloropropionic acid solution; (3), slowly dropwise adding the solution in the step (2) into the turbid liquid in the step (1), and performing reduced pressure distillation, dissolution and acidification, extraction and reduced pressure distillation on obtained reaction liquid, so as to obtain white solid, namely the R-(+)-2-(4-hydroxyphenoxy) propionic acid. The synthesis method has the advantages of simple synthesis route, mild reaction condition, high product yield, high product optical purity ee value, high recovery rate of hydroquinone, less produced three wastes and low energy consumption.

The invention discloses a synthesis method of L-2-sodium chloropropionate. Hydrochloric acid is directly sucked or pumped into a reaction kettle, and solid L-2-alanine is put into it, and the temperature is cooled to 0°C by an ice bath. Next, add the prepared sodium nitrite in portions, stop stirring after the reaction is over, let it stand for 2 to 3 hours, and then carry out suction filtration, and put the L-2-chloropropionic acid filtrate obtained after the suction filtration in a separate Extraction in a liquid funnel oscillator, after standing for stratification, the obtained extracts were combined, lye was added to the combined extracts for neutralization reaction, and the layers were left to stand, and the obtained oil layer was dichloromethane solvent. The aqueous layer is an aqueous solution of L-2-sodium chloropropionate. The present invention directly adds lye to the dichloromethane extract of L-2-chloropropionic acid for neutralization, replaces distillation with layering, and omits the distillation recovery process of the whole dichloromethane, which not only greatly improves the efficiency, but also greatly saves energy consumption.

The invention discloses a process for preparing high-optical-purity R-(+)-2-chloropropionic acid through an ester exchange method. The process comprises the following steps: placing ethyl chloropropionate in a reactor, sequentially adding formic acid with the mass fraction of 94% and strong-acid cation exchange resin under stirring, slowly heating to 54DEG C, extracting ethyl formate, continuously heating, and recovering formic acid; and forming a negative pressure after the recovery of formic acid, and extracting R-(+)-2-chloropropionic acid. The process has the advantages of simple technology, no strong acidic tails, environmental protection and short production period, and the optical purity and the yield of the prepared R-(+)-2-chloropropionic acid are not smaller than 99% and not smaller than 90% respectively.

The invention discloses a synthesis method of N-(2-chloride)-propionyl-glutamine. The synthesis method comprises the steps of reacting L-ethyl lactate with thionyl chloride under the presence of catalyst, distilling reaction liquor into alkaline liquor for hydrolyzing to obtain 2-chloropropionic acid; reacting the 2-chloropropionic acid with L-glutamine to obtain N-(2-chloride)-propionyl-glutamine under the presence of the catalyst, and other steps. The synthetic route is simple, the synthesis method is novel, simple and convenient in technique, and high in product yield and purity, the catalyst is low-cost and easily available, the environment is not influenced, and N-(2-chloride)-propionyl-glutamine is suitable for industrial production.

The invention discloses a [ethyl (R)-(+)-beta-(1-methylimidazole)-propionate]X chiral ionic liquid and a synthesis method which is used for solving the technical problem that imidazole type chiral ionic liquid prepared by the existing preparation method has high liquid melting point and low yield. The technical scheme is as follows: (S)-(-)-2-chloropropionic acid and (S)-(-)-2-bromopropionic acid are taken as raw materials and undergo esterification reaction with absolute ethyl alcohol to generate stable (S)-(-)-2-chloropropionic acid ethyl ester or (S)-(-)-2-bromopropionic acid ethyl ester; the (S)-(-)-2-chloropropionic acid ethyl ester or (S)-(-)-2-bromopropionic acid ethyl ester undergoes alkylation reaction with N- methylimidazole to generate chlorinated ethyl (R)-(+)-beta-(1-methylimidazole)-propionate or brominated ethyl (R)-(+)-beta-(1- methylimidazole)-propionate chiral ionic liquid; the chlorinated ethyl (R)-(+)-beta-(1- methylimidazole)- ropionate or brominated ethyl (R)-(+)-beta-(1- methylimidazole)-propionat chiral ionic liquid is used as an intermediate to undergo the anion exchange reaction with salts containing anions such as BF4<->, PF6<->, SCN<->, CH3COO<-> so as to obtain the [ethyl (R)-(+)-beta-(1- methylimidazole)-propionate] X chiral ionic liquid. The melting point of the [ethyl (R)-(+)-beta-(1- methylimidazole)-propionate] X chiral ionic liquid is reduced to minus 40 to minus 36 DEG C from 5 to 16 DEG C of the melting point of the background art; the yield of the [ethyl (R)-(+)-beta-(1- methylimidazole)-propionate] X chiral ionic liquid is increased to 52.8 to 60.5% from 20 to 35% of yield of the background art.

The invention discloses a method for resolution of racemization 2-chloropropionic acid by adopting a capillary electrophoresis separation-diode array detection technique. The method comprises the steps of: adding a chiral resolution agent, an organic solvent and a cation surfactant into a prepared buffer solution respectively and performing ultrasonic mixing to obtain a capillary electrophoresis operation buffer solution; using the buffer solution as an electrophoresis medium for resolution to obtain R-2-chloropropionic acid and S-2-chloropropionic acid monomers; calculating an enantiomer excessive value according to a chromatogram peak area; monitoring product quality according to the value. The method can achieve base line separation of the R-2-chloropropionic acid and S-2-chloropropionic acid monomers, and has the characteristics of good separation degree, low cost and simple and convenient operation.

The invention discloses a method for selectively increasing haloacid dehalogenase yield. Pseudomonas strains DEH138 are adopted according to a mechanism that inducers induce microorganisms to generate induced enzymes, and a proper carbon source is selected and optimized to specifically increase L-2-haloacid dehalogenase yield. To be more specific, inducer halogenated compounds (chloroacetic acid, iodoacetic acid, 2-propanoate, 2-chloropropionic acid, 2-bromopropionate, 3-chloropropionic acid, 2-chlorobutyric acid, 2-bromobutyric acid, 2-chloride propionamide and 2-bromide propionamide) are added in a logarithmic phase or synchronously in mineral basal media containing auxiliary carbon sources (glycolic acid, lactic acid, hydroxybutyric acid or glucose) respectively, so that induced expression of L-2-haloacid dehalogenase can be promoted; meanwhile, quantity of D-2-haloacid dehalogenases different in chiral selectivity is kept stable, and the L-2-haloacid dehalogenase yield is finally selectively increased. The method is a novel production mode for acquiring dehalogenases with chiral selectivity.

The invention discloses a synthetic method of L-2-chloropropionic acid. The synthetic method comprises the steps of firstly dissolving L-alanine into hydrochloric acid, introducing nitrosyl chloride and hydrogen chloride gas for reaction, after the raw materials are converted, filtering, continuing to stir for 1-2 hours, and an alkaline reagent for neutralization, extracting by virtue of an organic solvent, combining organic phases, drying by virtue of anhydrous calcium chloride, filtering, and carrying out rectification, so as to obtain a product, namely L-2-chloropropionic acid. The method has the advantages that the operation is simple, and the emission of wastewater is reduced; and by taking nitrosyl chloride with relatively high activity as a diazotization regent, aliphatic amino canbe rapidly converted into chlorine, so that the raw material conversation rate and the yield are greatly increased, the yield can reach 90% or above, an original configuration is not reversed in the reaction process, and the optical purity ee value can reach 99.1%.

The invention discloses a method for synthesizing the intermediate of agricultural bactericide fenoxanil and relates to a process for synthesizing an agricultural intermediate. The method comprises the following steps: putting 2,4-dichlorophenol, 2-chloropropionic acid, potassium hydroxide and surfactant in a dimethyl sulfoxide solvent, keeping a reaction temperature between 20 and 80 DEG C, keeping the temperature after the reaction is finished, neutralizing the reaction solution with sulfuric acid, filtering the neutralized reaction solution and distilling filtrate at a reduced pressure to remove the solvent; and taking a solid substance, adding normal hexane into the solid substance, cooling the mixture to room temperature, and filtering the mixture to obtain 2-(2,4-dichlorophenoxy) propionic acid. Using a solvent in place of water as a medium, the synthesis method of the invention improves condensation yield to 90 percent, reduces the discharge of water containing phenol during reaction and reduces production cost by recycling the solvent.

A process for preparing (S)-(-)-2-chloropropionate and (R)-(+)-2-chloropropionic acid includes such steps as selective hydrolytic reaction of dl-2-chloropropionate in reaction medium under existence of pig steapsase, and separating two products from the resultant liquid.

The invention discloses an industrial method for synthesizing 2-(4-methoxyphenoxy)-propionic acid through phase transfer, which comprises the following steps of: stirring and mixing 4-Methoxyphenol, sodium hydroxide, a phase transfer catalyst and water, and reacting at normal temperature and normal pressure for 10 to 20 minutes to obtain mixed feed liquid; adding 2-chloro-propanoic acid and an organic phase into the mixed feed liquid, and reacting for 0.5 to 1.5 hours to obtain a product of 2-(4-methoxyphenoxy)-propionic acid; regulating the reaction liquid subjected to reaction to be acid byusing HCl or sulfuric acid solution, and standing to separate a water phase and the organic phase; and evaporating organic phase separation liquid to remove a solvent, and performing acid-base recrystallization to obtain the 2-(4-methoxyphenoxy)-propionic acid. When the reaction is finished, the yield of the 2-(4-methoxyphenoxy)-propionic acid is over 90 percent, the reaction temperature is reduced to 40-60 DEG C, the reaction time is only 0.5 to 1.5 hours, and the content of 2-(4-methoxyphenoxy)-propionic acid in the final product is 99.5 percent.

The invention provides a synthesis method of high-purity D-2-chloropropionyl chloride. A process path of chlorination, hydrolysis and chloroacylation of L-methyl lactate is adopted. Specifically, the synthesis method sequentially comprises the following steps: (1) the synthesis of D-methyl-2-chloropropionate: dropwise adding thionyl chloride into the mixed solution of the L-methyl lactate and pyridine, carrying out vacuum stirring, increasing the temperature to 55-90 DEG C, reacting for 1-5h, reducing the temperature to 25-35 DEG C, exhausting air, washing and separating, wherein the L-methyl lactate and the thionyl chloride are used as raw materials and the pyridine is used as a catalyst; (2) the synthesis of D-2-chloropropionic acid: hydrolyzing methyl-2-chloropropionate under the action of a sodium hydroxide solution, and carrying out chloroform extraction; and (3) the synthesis of D-2-chloropropionyl chloride: dropwise adding the thionyl chloride into the mixed solution of D-2-chloropropionic acid and the catalyst, increasing the temperature to 70-80 DEG C, reacting for 3-5 hours, and carrying out vacuum rectification to obtain a target product. The process path has the advantages that raw materials are easily available; synthesis steps are simple, safe and reliable; the waste gas generated in the production can be easily disposed; therefore, the process path is suitable for industrial production.

The invention discloses a method for resolution of racemization 2-chloropropionic acid by adopting a capillary electrophoresis separation-diode array detection technique. The method comprises the steps of: adding a chiral resolution agent, an organic solvent and a cation surfactant into a prepared buffer solution respectively and performing ultrasonic mixing to obtain a capillary electrophoresis operation buffer solution; using the buffer solution as an electrophoresis medium for resolution to obtain R-2-chloropropionic acid and S-2-chloropropionic acid monomers; calculating an enantiomer excessive value according to a chromatogram peak area; monitoring product quality according to the value. The method can achieve base line separation of the R-2-chloropropionic acid and S-2-chloropropionic acid monomers, and has the characteristics of good separation degree, low cost and simple and convenient operation.