| 2-Chloropropionic acid can be used in the synthesis of a number of chemical intermediates such as pesticides,dyestuffs,and agriculture chemicals.However,only the agrochemicals synthesized from optical active 2-chloropropionic acid have higher physiological and pharmacological activities.When employing racemic 2-chloropropionic acid to synthesize pesticides and medicine intermediates,the corresponding products have low activities and even lead to the environmental contamination.So it is valuable to produce optical active 2-chloropropionic acid.In this article,2-chloropropionic acid was taken as the model compound,the basic rule of the PPL,CLL and CRL catalyzing the selective ester hydrolyze to prepare this compound was studied,the optimal lipase and the optimal reaction conditions of enzyme resolution were determined. In order to overcome some disadvantage from the free enzyme catalysis, a novel support PEI/D152 was prepared,the free CRL was immobilized on this carrier.Then,the immobilized lipase was applied in the resolution of 2-chloropropionic acid ester.The experimental results indicated that,the optimal condition to prepare the novel support PEI/D152 were:PEI concentration at 6g/L, temperature at 35℃.The linkage amount of PEI can reach 150mg/g(carrier). The lipase CRL could be well aggradated onto this support.The studies on immobilization conditions showed that the optimal amount of lipase,the optimal pH,the optimal temperature were 40mg,7.2 and 25℃.The immobilized lipase was much more stable than free lipase in wide scope of temperature and pH.The obtained immobilized lipase was applied in the catalysis resolution of racemic 2-chloropropionic acid ester,and it is discovered the immobilized lipase still maintained the catalysis predominance.When the reaction conversion rate was under 50%, (s)-2-chloropropionic acid enantiomer excessive would achieve above 89%. After being reused for 3 cycles,the activity of the immobilized lipase was about 65%.
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