Method for producing R-(-)- benzoglycolic acid

Abstract

The invention relates to a preparation method of R-(-)-mandelic acid and the steps are that: mandelic acid ethyl ester is taken and added in a reactor, then a ionic liquid, a tris(hydroxymethyl)aminoethane-hydrochloric acid buffer solution and a lipase catalyst are added; each milliliter of the ionic liquid is added with 0.1g to 0.3g of the mandelic acid ethyl ester, the amount of lipase is 2.5 percent to 7.5 percent of the weight of the mandelic acid ethyl ester, the ionic liquid: the buffer solution is equal to 1: 1 to 8 accounted by volume ratio, the pH scope of the buffer solution is 6 to 8.5; then reaction is carried out for 5.0 to 10 hours in a constant temperature water bath shaker, filtration is carried out for enzyme removal and water removal, the solids of the mandelic acid and the mandelic acid ethyl ester are obtained by ethyl acetate extraction and rotation evaporation; then n-hexane is added and the R-(-)-mandelic acid is obtained by filtration. The preparation method of the R-(-)-mandelic acid of the invention has simple technique, mild reaction conditions and small environmental pollution; the ionic liquid is taken as a reaction medium, thereby greatly shortening reaction time, the obtained product has high stereoselectivity, the ee value of the product is 60 percent at most, and the yield can achieve 92 percent.

Description

technical field [0001] The technical solution of the present invention relates to the biological synthesis of mandelic acid, specifically the preparation method of R-(-)-mandelic acid. Background technique [0002] Chiral drug refers to a single enantiomer compound drug with medicinal physiological activity. When drugs with different chiralities act on organisms, there are often significant differences in biological activity, metabolic process, and toxicity. With the development of modern drug research technology, chiral drugs and related technologies have become the research hotspots of current drugs and related disciplines. According to incomplete statistics, the total number of drugs on the market in the world is 1,850, including 523 natural and semi-synthetic drugs, of which 517 are chiral drugs; 1,327 synthetic drugs, of which 528 are chiral drugs. Chiral drugs have become one of the directions of international new drug research and development. [0003] Mandelic acid...

AI Technical Summary

Problems solved by technology

Among them, the chiral chromatographic column is prepared for resolution, and the obtained product has high purity, and the variable range of the separated sample is narrow, but due to the need for expensive chiral additives, it is limited to detection and laboratory preparation; the yield of the chemical method is low, and the optical Low purity, complex production process, high energy consumption, serious environmental pollution, high toxicity and high cost; the preparation of optically pure chiral compounds by biological methods has mild reaction conditions, single product, stereoselectivity, regioselectivity and chemoselectivity Higher, and can complete some reactions that are difficult to carry out in chemical synthesis, and become the focus of current research.

Patent "A method for preparing (R)-mandelic acid by asymmetric splitting of microorganisms" (CN1840671), firstly, the whole cell of the microorganism is obtained from a microorganism through fermentation and culture, and then the whole cell is used as a catalyst for splitting, The ee value of the obtained product is more than 90%, but the reaction period is long. Except for the microbial cultivation process, only the step of splitting reaction takes 24-72 hours