In this work, we synthesized n-octylpyrazinium bromide（G-Br） and n-octylpyrazinium hexafluorophos- phate（G-PE6） as model guests and studied their host-guest complexation with 1,4-dimethoxypillar[5]arene（DMP5A）. ...In this work, we synthesized n-octylpyrazinium bromide（G-Br） and n-octylpyrazinium hexafluorophos- phate（G-PE6） as model guests and studied their host-guest complexation with 1,4-dimethoxypillar[5]arene（DMP5A）. Effect of alkylpyrazinium counterions on the host-guest recognition was investigated. Based on the lH NOESY spectra, the binding site of DMP5A with G-PF6 is the same as that of DMP5A with G-Br. However, G-PF6 forms a stronger complex with DMP5A than G-Br, owing to that hexafluorophosphate forms weaker doubly inonic H-bonds with ammonium cation than bromide ion in chloroform, which leads to some aggregates that could be dissociated with the addition of DMP5A.展开更多
基金Supported by the National Natural Science Foundation of China（No.21204022）, the Research Fund for the Doctoral Program of Higher Education of China（No.20120076120005）, the Fundamental Research Funds for the Central Universities of China and the Large Instruments Open Fundation of East China Normal University, China（No.201409251425）.
文摘In this work, we synthesized n-octylpyrazinium bromide（G-Br） and n-octylpyrazinium hexafluorophos- phate（G-PE6） as model guests and studied their host-guest complexation with 1,4-dimethoxypillar[5]arene（DMP5A）. Effect of alkylpyrazinium counterions on the host-guest recognition was investigated. Based on the lH NOESY spectra, the binding site of DMP5A with G-PF6 is the same as that of DMP5A with G-Br. However, G-PF6 forms a stronger complex with DMP5A than G-Br, owing to that hexafluorophosphate forms weaker doubly inonic H-bonds with ammonium cation than bromide ion in chloroform, which leads to some aggregates that could be dissociated with the addition of DMP5A.
