有机化学 ›› 2016, Vol. 36 ›› Issue (3): 653-658.DOI: 10.6023/cjoc201509015 上一篇    下一篇

研究简报

七元瓜环与1,7-二(2-苯并咪唑)庚烷的相互作用及自组装

易君明a,b, 陈明华b, 薛赛凤a, 陶朱a   

  1. a 贵州大学贵州省大环化学与超分子化学重点实验室 贵阳 550025;
    b 兴义民族师范学院生物与化学学院 兴义 562409
  • 收稿日期:2015-09-11 修回日期:2015-10-31 出版日期:2016-03-25 发布日期:2015-11-06
  • 通讯作者: 陶朱 E-mail:gzutao@263.net
  • 基金资助:

    国家自然科学基金(No. 21272045)资助项目.

Interaction and Supramocular Self-Assembly of Cucurbit[7]uril with 2,2'-(Heptane-1,7-diyl) Dibenzimidazolium Chloride

Yi Junminga,b, Chen Minghuab, Xue Saifenga, Tao Zhua   

  1. a Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province, Guizhou University, Guiyang 550025;
    b College of Biology and Chemistry, Xingyi Normal University for Nationalities, Xingyi 562409
  • Received:2015-09-11 Revised:2015-10-31 Online:2016-03-25 Published:2015-11-06
  • Supported by:

    Project supported by the National Natural Science Foundation of China (No. 21272045).

利用1H NMR法、紫外吸收光谱法、荧光发射光谱法和单晶X射线衍射等方法考察了七元瓜环(Q[7])与氯化1,7-二(2-苯并咪唑)庚烷(SBHt)在酸性溶液中的相互作用过程及组装模式. 首先考察了主客体相互作用对客体pKa的影响, 以确定研究主客体相互作用以及组装过程的实验条件. 1H NMR滴定实验结果表明, 在水溶液中主客体可形成1:1和2:1的主客体包结配合物, 当主客体物质的量之比为1:1时, Q[7]包结SBHt的烷基链, 两端苯并咪唑基团处于瓜环端口外侧; 当主客体物质的量之比为2:1时, 两个Q[7]分别包结同一SBHt分子的两端苯并咪唑基团, 这一实验结果得到荧光发射光谱的佐证. Q[7]与SBHt形成1:1的主客体包结配合物的晶体结构表明, 客体烷基链在瓜环空腔内发生折叠以使其通过离子偶极及氢键与Q[7]有效作用.

关键词: 七元瓜环, 1,7-二(2-苯并咪唑)庚烷, 相互作用, 超分子组装, 晶体结构

The interaction and supramolecular self-assembly of cucurbit[7]uril (Q[7]) with 2,2'-(heptane-1,7-diyl) dibenzimidazolium chloride (SBHt) in aqueous solution were investigated by 1H NMR spectroscopy, fluorescence spectroscopy in details. The pKa shift of guest in the presence of Q[7] was first investigated in order to decide the pH of medium condition for investigation of host-guest interaction and supramolecular self-assembly. 1H NMR spectroscopy analysis revealed that Q[7] included the alkylene chain of guest and formed a simple 1:1 host-guest binding model complex at a low rate of NQ[7]/NSBHt, while at higher ratios of Q[7] to guest, two host Q[7] prefer to include the benzimidazolyl moieties of guest and formed a dumbbell shape inclusion complex. The typical reversible interaction modes were controlled by concentration of the ratio of host and guest, and the process was further conformed by fluorescence spectroscopy technology. The single X-ray crystal structure analysis showed a 1:1 host-guest inclusion complex in which the alkyl chain of SBHt was folded in order to effectively interact with Q[7] through ion-dipole interactions and hydrogen bonding.

Key words: cucurbit[7]uril, 2,2'-(heptane-1,7-dily)dibenzimidazolium, interaction, supramolecular self-assembling, crystal structure