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Study of the counter anions in the host-guest chemistry of cucurbit[8]uril and 1-ethyl-1'-benzyl-4,4'-bipyridinium.

ABSTRACT: A series of 1-ethyl-1'-benzyl-4,4'-bipyridinium compounds with different counter anions (BEV-X2, where the X is Cl, Br, I, PF6, ClO4) were synthesized. By using of NMR, MS, electrochemistry, Na2S2O4-induced redox chemistry, and UV-Vis, the role of the different counter anions in the host-guest chemistry of cucurbit[8]uril (CB[8]) was studied for the first time. The result demonstrated that BEV-X2 can form a 1?:?1 host-guest complex with CB[8] in water. Theoretical calculation further suggested that the viologen region was threaded through the cavity of CB[8], while the corresponding counter anions were located outside the cavity. Some difference can be observed on UV-Vis titration and Na2S2O4-induced redox chemistry, which showed that the counter anions have some effect on the host-guest chemistry. All these provide new insights into CB[8] host-guest system.

SUBMITTER: Ji H

PROVIDER: S-EPMC3678417 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Study of the counter anions in the host-guest chemistry of cucurbit[8]uril and 1-ethyl-1'-benzyl-4,4'-bipyridinium.

Ji Hailong H Liu Fengyu F Sun Shiguo S

TheScientificWorldJournal 20130527

A series of 1-ethyl-1'-benzyl-4,4'-bipyridinium compounds with different counter anions (BEV-X2, where the X is Cl, Br, I, PF6, ClO4) were synthesized. By using of NMR, MS, electrochemistry, Na2S2O4-induced redox chemistry, and UV-Vis, the role of the different counter anions in the host-guest chemistry of cucurbit[8]uril (CB[8]) was studied for the first time. The result demonstrated that BEV-X2 can form a 1 : 1 host-guest complex with CB[8] in water. Theoretical calculation further suggested t ...[more]

PMID: 23781157

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