二(2-乙基己基)磷酸与酒石酸衍生物复合萃取拆分扁桃酸外消旋体

Enantioseparation of Mandelic Acid Enantiomers by Co-extractants with Di(2-ethylhexyl)phosphoric Acid and Tartaric Acid Derivatives

本文研究了扁桃酸对映体在含二(2-乙基己基)磷酸(D2EHPA)与酒石酸衍生物复合手性选择剂的正辛醇-水两相体系中的萃取分配行为,考察了酒石酸衍生物的种类和初始浓度、D2EHPA的初始浓度、扁桃酸的初始浓度、萃取温度对分配系数和分离因子的影响。结果显示,复合手性选择剂能提高分配系数和分离因子,D2EHPA与D-酒石酸衍生物的复合手性选择剂与L-扁桃酸对映体比与D-扁桃酸对映体形成更稳定的非对映体复合物;且D2EHPA与二对甲基苯甲酰酒石酸(DTTA)的复合手性选择剂的手性选择性大于D2EHPA与二苯甲酰酒石酸(DBTA)的复合手性选择剂;同时,扁桃酸的初始浓度、萃取温度对分配系数和分离因子的影响较大。

The distribution behavior of mandelic acid （MA） enantiomers was examined in a two-phase aqueous-organic solvent mixture containing di （2-ethylhexyl） phosphoric acid （D2EHPA） and tartaric acid derivatives as co-extractants. The influence of tartaric acid derivative＇s species and its initial concentration, the initial concentration of D2EHPA, D, L-MA and extractive equilibrium temperature on distribution ratio and enantioselectivity were studied. The results showed that both the distribution ratio and enantioselectivity were greatly improved by using D2EHPA and tartaric acid derivatives as coextractants than using tartaric acid derivatives individually; the co-extractants of D2EHPA and D-tartaric acid derivatives studied all formed more stable diastereomeric complexes with IrMA than with D-MA; the enantioselectivity of D2EHPA and di-p-methylbenzoyl tartaric acid （DTI＇A） co-extractants were better than D2EHPA and dibenzoyl tartaric acid （DBTA） coextractants; The influence of the initial concentration of D, L-MA and the extractive equilibrium temperature on distribution ratio and enantioselectivity were significant.