摘要
通过红外光谱、紫外光谱及核磁共振波谱表征了四丁基碘化铵盐对正己烷溶液中二碘四氟乙烷(C_2F_4I_2)的卤键吸附作用.结果表明,固液两相间卤键作用引起的光谱变化同溶液中形成卤键复合物的光谱变化一致;四丁基氯化铵的吸附作用强于四丁基溴化铵和四丁基碘化铵,而具有较长烷烃链的季铵盐——十六烷基三甲基氯/溴化铵对C_2F_4I_2则完全没有吸附作用.对四丁基氯化铵与4种碘代全氟烷烃间卤键作用强度的测定结果显示,尽管溶液中一碘代全氟烷烃与氯阴离子间的卤键作用强于二碘代全氟烷烃,但在固液两相间四丁基氯化铵对二碘代全氟烷烃的吸附强于一碘代全氟烷烃.利用拉曼光谱研究该体系时,发现卤键的形成可增强碘代全氟烷烃的拉曼光谱.
The adsorption of 1,2-diiodotetrafluoroethane（C2F4I2） on tetrabutyl ammonium iodide（ Bu4 N＋I-）was analyzed by IR,UV and19 F NMR spectroscopies. The according spectrum changes of IR,UV and 19 F NMR indicated that halogen bond complexes were formed in solution, which demonstrated that the adsorption was due to the C—I…I-halogen bonding interactions. The adsorptivities of five quaternary ammonium salts were compared and the experiment results showed that adsorptivity was Bu4N~＋Cl^- Bu4N~＋Br^-Bu4N~＋I^-. Hexadecyl trimethyl ammonium chloride and hexadecyl trimethyl ammonium bromide,which have long alkyl chain,had absolutely no adsorption to C2F4I2. It is probably because that the long alkyl chains prevented halide anion from closing to C2F4I2. The adsorption of four iodoperfluoroalkanes（ C4F8I2,C4F9I,C6F（12）I2,C6F（13）I） by Bu4N~＋Cl^- salt were investigated. The results showed that although halogen bonds in the monoiodoperfluoroalkanes（ monoiodo-PFAs） complexes were stronger than those in the diiodoperfluoroalkanes（ diiodo-PFAs） complexes as estimated by Raman spectra in solution,the adsorptivities of Bu4N~＋Cl^- for the diiodo-PFAs were stronger than those for the monoiodo-PFAs at the solid/liquid interface because the odds of forming halogen bond of diiodo-PFAs is double that of monoiodo-PFAs. Besides,it was found that the formation of halogen bonds could enhance the Raman signals of iodoperfluoroalkanes.
作者
阎小青
刘秋双
刘云凤
牛侨
YAN Xiaoqing;LIU Qiushuang;LIU Yunfeng;NIU Qiao(School of Public Health, Shanxi Medical University, Taiyuan 030001, China)
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2018年第4期743-748,共6页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:81502851)
中国博士后科学基金(批准号:2014M561208)
山西医科大学博士启动基金(批准号:055235)资助~~
关键词
卤键
碘代全氟烷烃
季铵盐
卤阴离子
吸附
Halogen bond
Iodoperfluoroalkane
Tetrabutyl ammonium halide
Halide anion
Adsorption
