摘要:研究了一种价格低廉的制备旋光性(R)-2-戊基环戊酮的方法,利用该方法在短时间内合成的(R)-2-戊基环戊酮具有很高的产量、高的不对称产率以及良好的加工性能。制备(R)-2-戊基环戊酮的过程如下:先用作为旋光异构体混合物的2-戊基环戊酮与异丁酸酐进行反应,然后用固定化的Novozymes435水解之前得到的异丁酸戊基环戊烯醇酯,获得目标产物(R)-2-戊基环戊酮。在酶水解反应中,本文研究了脂肪酶不同颗粒密度、温度、溶剂以及搅拌速率对结果的影响。结果表明,最佳的反应条件是酶的密度为400颗/g、温度为35℃、甲醇含量为60%以及搅拌速率为400r/min。在最佳反应条件下,异丁酸戊基环戊烯醇酯的转化率达到了99%,(R)-2-戊基环戊酮的e.e.(对映体超量)值达到了65.70%。酶可以通过95%乙醇冲洗后回收再使用,在使用6或7次后酶的活性仍然保持不变。22957 毕业论文关键词:ɑ-戊基环戊酮;水解;固定化Novozymes435脂肪酶;异丁酸戊基环戊烯醇酯
The preparation of chiral ɑ-pentylcyclopentanone
Abstract: Provided that a method for inexpensively producing optically active (R)-2-pentylcyclopentanone with a high yield and a high asymmetric yield and with good workability in a short process. A method for producing optically active (R)-2-pentylcyclopentanone, comprising allowing 2-pentylcyclopentanone as a mixture of optical isomers to react with isobutyric anhydride, and hydrolyzing the obtained 2-pentylcyclopentanone enol ester with immobilized Novozymes435 to produce (R)-2-pentylcyclopentanone. The effect of enzyme granularity, temperature, solvent and rotational speed was investigated for the enzyme hydrolyzing reaction. The optimum conditions were determined as enzyme granularity=400piece/g, T = 35 ℃, CH3OH/H2O=60/40(wt/wt), rotational speed=400r/min. The conversion of 2-pentylcyclopentanone enol ester is 99%, and the e.e. of the (R)-2-pentylcyclopentanone is 65.70% under the optimum conditions. The enzyme is recovered by washing with 95% ethanol, and the activity of the enzyme remains constant after six (seven) runs.
Keywords: (R)-2-pentylcyclopentanone; hydrolyzing; immobilized Novozymes435; 2-pentylcyclopentanone enol ester