本研究旨在探討含飽和水之有機溶劑中進行外消旋2,2,2-trifluoroethyl α-chlorophenylacetate的酵素水解動態動力分割。在不同來源脂肪分解酵素lipase MY、Novozyme 435、papaya lipase、Pseudomonas cepacia lipase催化的水解反應中，以lipase MY具備最佳的鏡像選擇性。再以異丙醇前處理lipase MY來提升酵素選擇性與反應性，並且在不同極性的有機溶劑及反應溫度下進行反應，找出最佳的反應條件後，進一步以Michaelis-Menten酵素反應機構配合酵素失活與產物抑制作用進行動力學分析。在上述的反應條件下，於反應溶液中添加消旋觸媒三辛基胺進行動態動力分割反應，實驗結果顯示三辛基胺不僅具有消旋的能力，意外地更發現其具有活化酵素而大幅度地提高反應活性的功能。在高濃度三辛基胺快速消旋作用下，當反應總轉化率達97%時，可獲得產物鏡像過剩比值約為90%，顯示獲得不錯的動態動力分割的成效。然而結合了酵素動力分割模式、鹼消旋與水解、三辛基胺活化作用以及酵素失活後，發現理論模式與實驗值之間的偶合結果仍有誤差，顯示理論模式改進尚有努力空間。

The purpose of this research is aimed to develop an enzymatically dynamic kinetic resolution process in water-saturated organic solvents with (R, S)-α-chlorophenylacetic acid trifluoroethyl ester as the substrate. Different lipases such as lipase MY、Novozyme 435、papaya lipase and lipase PS were firstly screened to enantioselectively hydrolyze the substrate where lipase MY was selected as the best enzyme. Furthermore, lipase MY pre-treated with 2-propanol demonstrated a much better enantioselectivity and specific activity. The kinetic analysis using a Michaelis-Menten kinetics by considering the effects of lipase deactivation and product inhibition was performed at the optimum condition.
A dynamic kinetic resolution process for the lipase-catalyzed hydrolysis of racemic α-chlorophenylacetic acid trifluoroethyl ester was then developed by using 2-propanol-treated lipase MY and trioctylamine as the biocatalyst and racemization catalyst, respectively. Results showed that trioctylamine not only catalyzed the racemization but also dramatically enhanced the enzyme activity. When a high trioctylamine concentration was used, high enantiomeric excess for the product eeP = 90% at the racemate conversion of 97% was obtained. However, more efforts on improving the kinetic model were needed in order to have good agreements between experimental data and theoretical results.

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葉秀林，立體化學，五南出版社，台北市，2002.