52 results about "2-Chloropropionic acid" patented technology

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.