Inclusion behavior of oxybutynin with hydroxypropyl-β-cyclodextrin

Inclusion behavior of oxybutynin (OBN) with hydroxypropyl-β-cyclodextrin (HP-β-CD) was investigated by ultraviolet absorption spectrum and fluorescence spectrum. A reliable determination of the complex stoichiometry was provided by the continuous variation technique. Alcohol was added to further investigate the mechanism of the inclusion behavior. Thermodynamic constants ΔG, ΔH and ΔS for inclusion interaction of OBN and HP-β-CD were determined. The results show that host-guest complex with molar ratio of 1:1 is formed, and inclusion stability constant between OBN and HP-β-CD is 54.9 L/mol determined by ultraviolet spectrum and 11.1 L/mol determined by fluorescence spectrum. OBN has weak binding ability with HP-β-CD in aqueous solution (stability constant <10² L/mol) and addition of alcohol leads to a decrease of stability constant, which indicates that the hydrophobic force contributes to the inclusion process. ΔG, ΔH and ΔS are all less than zero, which indicates that the inclusion process is a spontaneous and exothermic process.     

Enantioselective extraction of clorprenaline enantiomers with hydrophilic selector of sulfobutylether-β-cyclodextrin by experimentand modeling简

Enantioselective extraction of hydrophobic clorprenaline （CPE） enantiomers from organic phase to aqueous phases with sulfobutylether-β-cyclodextrin （SBE-β-CD） as the selector was investigated with insight into a number of important process variables, such as the type of organic solvent, concentration of selector, pH, and temperature. Equilibrium of the extraction system was modeled using a reactive extraction modcl with a homogeneous aqueous phase reaction. The important parameters of this model were determined experimentally. The physical distribution coefficients for molecular and ionic CPE were determined as 0.3 and 8.93, respectively. The equilibrium constants of the complexation reaction with SBE-β-CD were determined as 152 and 110 L/mol for R- and S-CPE, respectively. Results show that the experimental data agree with the model predictions perfectly. Comprehensively considering the experiment and model, the extraction conditions are optimized and the best extraction conditions are： pH of 6.0, SBE-β-CD concentration of 0.04 tool/L, and temperature of 5 ℃, providing the enantioselectivity （a） of 1.25, the fraction of R-CPE （φR） in aqueous phase of 0.71 and performance factor （pf） of 0.025.     

多级离心逆流萃取萘普生对映体模拟及实验研究

基于萘普生(NAP)对映体的单级手性萃取数学模型和质量守恒定律,建立了多级离心逆流萃取萘普生对映体数学模型。采用Matlab语言编写程序模拟了相比、萃取剂浓度、水相pH值等参数对萃取相出口对映体过剩量和产率的影响,并经实验研究对模型模拟进行验证。结果表明:采用中间进料,对映体浓度[R,S-NAP]=0.025 mol·L^-1、萃取剂浓度[C]=0.050 mol·L^-1、相比W/O=7、水相pH=2.5、温度T=5℃时,经10级离心逆流萃取后萃取相出口S-NAP对映体过剩量为45%,相应的产率60%,实验结果和模型模拟值符合得很好。     

反应萃取分离2-苯基丁酸对映体的动力学

通过恒界面池法进行了羟乙基-β-环糊精反应萃取2-苯基丁酸对映体的动力学研究。采用双膜理论和均相反应模型描述了萃取过程的相际传质机理,并考察了搅拌速率、界面面积、对映体初始浓度和萃取剂初始浓度等因素对2-苯基丁酸对映体的萃取动力学的影响。实验结果表明羟乙基-β-环糊精与2-苯基丁酸对映体之间的包合反应属于“快反应”;2-苯基丁酸对映体反应分级数为1,羟乙基-β-环糊精反应分级数为2;（+）-2-苯基丁酸和（-）-2-苯基丁酸在278 K下的反应速率常数分别为2.829×10^-4、1.803×10^-4 m⁶·mol^-2·s^-1。该萃取动力学研究为大规模生产中的反应萃取过程的设计和操作以及设备的设计和过程强化提供了科学的依据。     

β-衣康酸单甲酯功能单体的合成

以衣康酸和无水甲醇为原料,在酸性催化条件下酯化合成β-衣康酸单甲酯.研究催化剂种类与用量、物料配比、反应温度、反应时间对β-衣康酸单甲酯收率的影响.得到的较佳合成工艺条件为:n(衣康酸):n(甲醇):n(苯甲酰氯)=1-3.5-0.043(摩尔比),反应温度65 ℃,反应时间30 min.粗产品用苯和石油醚的混合溶剂重结晶后,产物收率高达97.8%.采用FT-IR和1H-NMR对产物结构进行了表征.