【摘要】 研究有机溶剂中面包酵母催化2-氧代-4-苯基丁酸乙酯(OPBE)不对称还原合成(R)-2-羟基-4-苯基丁酸乙酯((R)-HPBE),分别考察有机溶剂种类、初始水含量、初始底物浓度、缓冲液pH值和添加剂等因素对OPBE转化率(COPBE)、HPBE产率(YHPBE)及(R)-HPBE的光学纯度(ee%)的影响。实验结果表明,乙醚为适宜反应介质,适宜pH为中性;反应初始水含量和初始底物浓度分别以w(H2O)=30 g/Lc、(OPBE)=5 mmol/L为佳。添加α-氯代苯乙酮(-αPC)对酵母预处理2 h后,(R)-HPBE的ee从35.52%提高为82.25%,COPBE和YHPBE分别从75.29%和46.02%提高到98.51%和75.82%。更多还原

【Abstract】 The asymmetric reduction of ethyl-2-oxo-4-phenylbutyrate(OPBE) catalyzed by bakers’ yeast(Saccharomyces cerevisiae) in organic solvent to synthesize optically active ethyl-2-hydroxy-4-phenylbutyrate (HPBE) was investigated in detail.The conditions for asymmetric reduction were also studied.The reaction was run in aqueous diethyl ether at 30℃ for 24h under the catalysis of bakers’ yeast,which preincubated for 2h in the presence of phenacyl chloride.As a result,both higher chemical yield(78.25%) and higher stereoselectivity(82.25% ee) were obtained at the optimum pH 7.0,dosage of water 30 g/L and substrate concentration 5 mmol/L,respectively.更多还原