手性溶剂萃取分离布洛芬对映体

Separation of ibuprofen enantiomers by chiral extraction with hydrophobic tartaric esters

研究了布洛芬对映体在含有疏水性L-酒石酸酯的1,2-二氯乙烷溶液及甲醇水溶液两相中的萃取分配行为,考察了不同烷基链长的L-酒石酸酯、D-酒石酸酯以及L-酒石酸酯的浓度、有机溶剂的种类和溶解布洛芬的甲醇水溶液浓度对分配系数K和分离因子α的影响。实验表明,L-酒石酸酯与布洛芬Ⅱ对映体形成的复合物稳定性比与布洛芬Ⅰ对映体形成的复合物稳定性要大,而D-酒石酸酯的萃取性能则与此相反,它与布洛芬Ⅰ对映体形成的复合物稳定性比与布洛芬Ⅱ对映体形成的复合物稳定性要大。有机溶剂的萃取性能为醇>1,2-二氯乙烷>烷烃,随着溶解布洛芬的甲醇水溶液中甲醇浓度的增大,分配系数K和分离因子α均降低,当甲醇的浓度为10%时,可以得到最佳的K和α。随着L-酒石酸酯浓度的提高,分配系数K和分离因子α先增大后减小,当L-酒石酸酯的浓度约为0.2mol·L-1时,K和α达到最大值;L-酒石酸酯的碳链长度对分配系数K和分离因子α也有很大的影响。

The distribution of ibuprofen enantiomers was examined in aqueous methanol solution and 1,2-dichloroethane organic solvent containing a chiral selector hydrophobic L-tartaric ester or D-tartaric ester. The influences of the length of alkyl chain of L-tartaric ester or D-tartaric ester, the concentration of L-tartaric ester, different organic solvents and the concentration of aqueous methanol solution on the partition coefficient （K） and separation factor （α） of ibuprofen, were investigated. L-tartaric ester formed more stable complex with Ⅱ-ibuprofen than with Ⅰ-ibuprofen- In contrast, D-tartaric ester formed more stable complex with Ⅰ-ibuprofen than with Ⅱ-ibuprofen. The extraction performance of organic solvents was different. For example, alcohols〉1, 2-dichloroethane〉alkanes. K and a were the highest when the concentration of aqueous methanol solution was 10%. With further increasing concentration of aqueous methanol solution, partition coefficient and separation factor decreased. With increasing concentration of L-tartaric ester, K and α increased firstly, and then decreased. K and a were the highest, when the concentration of L-tartaric ester was 0.2 mol · L^-1. The length of alkyl chain of L-tartaric esters and D-tartaric esters also had a great influence on K and α.