7474-05-7Relevant articles and documents
Preparation method of D-2-chloropropionyl chloride and D-2-chloropropionyl chloride
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Paragraph 0055; 0058-0059; 0065; 0068-0069; 0076; 0079-0080, (2021/03/13)
The invention is applicable to the technical field of synthesis of medical intermediates, and provides a preparation method of D-2-chloropropionyl chloride and D-2-chloropropionyl chloride, the preparation method comprises the following steps: adding L-ethyl lactate and a catalyst into a reaction vessel, dropwisely adding thionyl chloride at -10-10 DEG C, heating to 65-70 DEG C, and carrying out heat preservation reaction; after the reaction is finished, cooling to 10-30 DEG C, and carrying out reduced pressure concentration and other treatment to obtain ethyl D-2-chloropropionate; adding resin, anhydrous formic acid and water, heating to 70-100 DEG C, and reacting for 2-5 hours; after the reaction is finished, cooling to 10-30 DEG C, filtering, and distilling to obtain D-2-chloropropionicacid; and dropwise adding thionyl chloride at 0-5 DEG C, heating to 45-65 DEG C, carrying out heat preservation reaction, and carrying out vacuum concentration and distillation treatment to obtain the product. The method realizes 10kg-grade large-scale production of D-2-chloropropionyl chloride, and has the advantages of high yield, high purity, recyclable catalyst, and no need of rectification equipment.
Method for synthesizing (R)-2-chloropropionic acid by solid acid catalysis and trans-esterification reaction based on UIO-66
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Paragraph 0010; 0012; 0014, (2017/07/20)
The invention provides a method for synthesizing (R)-2-chloropropionic acid by a solid acid catalysis and trans-esterification reaction based on UIO-66. The method comprises the following steps: (1) preparation of a solid acid catalyst SO4/UIO-66; and (2) preparation of (R)-2-chloropropionic acid. According to the method, UIO-66 is adopted as a solid acid catalyst of a substrate, the catalyst has strong acidity, so that the catalyst can effectively catalyze the trans-esterification reaction for synthesizing (R)-2-chloropropionic acid, the transformation rate is higher than 98%, side effects are less, and the catalyst can be used repeatedly, and therefore, the generation of tailings is effectively avoided, the production cost is lowered, and environmental protection is facilitated.
Ester exchange method for preparing high purity R-(+) - 2-chloropropionic acid process of
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Paragraph 0016; 0017; 0018, (2016/10/07)
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.