Chin. J. Org. Chem. ›› 2013, Vol. 33 ›› Issue (07): 1451-1456.DOI: 10.6023/cjoc201212044 Previous Articles     Next Articles



易平贵, 阳习春, 刘金, 侯博, 于贤勇, 李筱芳, 汪朝旭, 郑柏树   

  1. 湖南科技大学化学化工学院 湘潭 411201
  • 收稿日期:2012-12-25 修回日期:2013-03-02 发布日期:2013-03-15
  • 通讯作者: 易平贵
  • 基金资助:

    国家自然科学基金(Nos. 21172066, 20971041);湖南省自然科学基金(Nos. 10JJ4011, 11JJ2007)和湖南省高校科技创新团队支持计划(No,[2012]318-17))资助项目.

Investigation of Excited-State Proton Transfer of 2-(3-Acetamido-2-pyridyl)benzimidazole in the Confined Nanocavity of Cucurbit[7]uril

Yi Pinggui, Yang Xichun, Liu Jin, Hou Bo, Yu Xianyong, Li Xiaofang, Wang Zhaoxu, Zheng Baishu   

  1. School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201
  • Received:2012-12-25 Revised:2013-03-02 Published:2013-03-15
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 21172066, 20971041), the Hunan Provincial Natural Science Foundation of China (No. 11JJ2007), the Science and Technology Innovative Research Team in Higher Educational Instituions of Hunan Province (No.[2012]318-17).

The interaction of 2-(3-acetamido-2-pyridyl)-benzimidazole (2-3Am2PyBI) with cucurbit[7]uril (CB7) macrocycle and the effect of inclusion on the proton transfer of 2-3Am2PyBI were studied by using emission fluorescence, 1H NMR spectra and quantum chemical calculation. By the way, the proton transfer of the dye with and without acetyl (2-3A2PyBI) was also studied. The results indicate that the acetyl promoted the process of proton transfer of the benzimidazole and the cationic form binds with CB7 easier than the other forms of the dye. The fluorescence studying at selected pHs suggest that the proton transfer process of the dye was retarded by interacting with CB7 nanocavity and the molar rate is host:guest=1:1 analyzed by the Benesi-Hildebrand method. The dye entered into the CB7 cavity with its benzene ring was proved by the 1H NMR titration experiment and the protonated forms were verified by the quantum calculation with fluorescence spectra.

Key words: proton transfer, cucurbit[7]uril, emission fluorescence, 1H NMR spectra, quantum calculation