双水相手性萃取拆分扁桃酸外消旋体  

Aqueous Two Phase Extraction for the Enantioseparation of Mandelic Acid Enantiomers

作　　者：王珍[1] 陈晓青[1] 焦飞鹏[1] 马国恒[1] 

机构地区：[1]中南大学化学化工学院,湖南长沙410083

出　　处：《分析科学学报》2009年第5期507-511,共5页Journal of Analytical Science

基　　金：国家自然科学基金(No.20805058)

摘　　要：研究了扁桃酸(MA)对映体在含β-环糊精(β-CD)手性选择剂的聚乙二醇(PEG)/(NH4)2SO4双水相体系中的萃取分配行为。考察了pH、PEG和(NH4)2SO4的质量分数、β-CD的浓度、MA的浓度与萃取温度等因素对拆分效果的影响。实验结果表明:双水相手性萃取具有很强的手性分离能力,β-CD对L-MA对映体的识别能力大于对D-MA对映体的识别能力;当温度为30℃、pH=1.0、PEG2000质量分数为30%、(NH4)2SO4质量分数为20%、β-CD的浓度为0.008 mol/L、扁桃酸的浓度为0.05 mol/L时,分离因子(α)达到2.46,上、下相对映体过剩值(e.e.%)分别为42.13%和40.43%。The distribution behavior of D,L-mandelic acid（MA） was examined in aqueous two-phase systems composed of polyethylene glycol（PEG） and ammonium sulfate [（NH4）2SO4] containing β-cyclodextrin（β-CD） as chiral selector.The influence of the pH,the mass fractions of PEG and（NH4）2SO4,the molecular weight of PEG,the initial concentrations of β-CD,D,L-MA and extractive temperature on the distribution behavior were studied.The results showed that β-CD is inclined to recognize L-MA;the enantioselectivities reached at 2.46 and the enantiometric excess （e. e.%） is 42.13% in the top phase and 40.43% in the bottom phase, respectively. Under the condition of the extractive temperature of 30 ℃, the pH values of the bottom phase is 1.0, the mass fraction of PEG and （NH4）2 SO4 is 30% and 20 %, the molecular weight of PEG is 2000, the initial concentration of fl-CD and D,L-MA is 0. 008 mol/L and 0.05 mol/L, respectively. Aqueous two-phase chiral-extraction has strong chiral separation ability, and has great significane for preparative separation of raeemic compounds.

关 键 词：扁桃酸 双水相萃取 手性拆分 聚乙二醇 Β-环糊精 

分 类 号：O657.8[理学—分析化学]