量化计算辅助解析磺酸基杯[6]芳烃在毛细管电泳分离R-和S-联萘酚中的作用

Assisted Elucidation for the Effect of Para-sulfonate Calix[6] Arene on the Capillary Electrophoresis Separation of R-and S-binaphthol Based on a Quantum Chemistry Calculation

杯芳烃对客体具有优异的识别作用,可作为毛细管电泳的添加剂.以R-和S-联萘酚(BINOL)为溶质探针,优化获得了R-和S-BINOL毛细管电泳的分离条件,用量子化学计算辅助研究了磺酸基杯[6]芳烃(SCx6)在电泳分离R-和S-联萘酚中的作用.结果表明,在电泳溶液为25 mmol.L-1醋酸铵+10 mmol.L-1SCx6的乙腈-水(6∶4,v/v)(pH8.75)、运行电压为+30 kV、检测波长为335 nm的条件下,R-和S-BINOL在48.5cm(有效长度40 cm)×50μm石英毛细管内可实现部分分离.用所建立的DFT-B3LYP/3-21+G*量化计算方法,获得了溶质R-和S-BINOL与SCx6形成的S-BINOL-SCx6、R-BINOL-SCx6超分子结构,直观地观察到了BINOL与SCx6之间的π-π疏水作用和氢键作用.超分子S-BINOL-SCx6、R-BINOL-SCx6的ΔG数值、稳定性与其电泳行为一致.

In this paper, the migration behaviors of axially chrial R- and S- binaphthol （BINOL） without symmetric carbon center by capillary electrophoresis （CE） using p -sulfonate calix[ 6 ] arene （SCx6） as the ad- ditive are reported. The influence of electrolyte concentration, SCx6 concentration, solvent and pH value of the running buffer on the separation of R - and S - BINOL is investigated. An increase of SCx6 concentration up to 10 mmol · L^-1 in the CE running buffer, R - and S - BINOL achieves a partial separation. The addition of SCx6, forming different supramolecular complexes with R - and S - BINOL, facilitates their separation. The supramolecular interaction mechanism is discussed through the quantum chemistry calculation using DFF -B3LYP/ 3 -21 ＋ G^＊ as the base group.