Cucurbituril Interactions With The Benzimidazole Derivatives

Supramolecular chemistry research object is a kind of aggregate that is complicated, orderly, And also has a special function under the condition of noncoral bond weak nutual effort jointing ,it's a kind of chemistry research supramolecular or supramolecular chemistry 's properties and application, nowadays supramolecular chemistry or host-guest chemistry has become one of the hot fields of chemical research . Due to their special structure, cucurbit[n]urils are becoming a series new hosts after crown ether, cyclodextrin and calixarene, and are one of the important investigation of the supramolecular chemistry.In this paper, The structures and optical properties of host-guest of cucurbit[n=6-8]urils with some benzimidazole derivatives (2-benzimidazolemethanol (gel), 2-benzimidazolepropionic(ge2) and 2-aminoben- zimidazole (ge3))have been investigated by ¹H NMR spectroscopy, electronic absorption spectroscopy and fluorescence Spectroscopy. The experimental results reveal that A-N_Q[n]/N_guest data and I_f-N_Q[n]/N_guest data for the same system can be well fitted to the same binding model. Particularly, the A-N_Q[n]/N_guest data and I_f-N_Q[n]/N_guest data and ¹H NMR determination for three Q[6]-ge(1-3) systems and three Q[8]-ge(1-3) systems are all fitted to a 1:1 and 1:2 binding model respectively.Moreover , the effect of pH for reciprocity between cucurbit[n=6-8]urils and some benzimidazole derivatives has been investigated. The experimental results reveal that the reciprocity of cucurbit[n=6-8]urils with some benzimidazole derivatives is remarkable in the condition of 0 < pH < 7.While the pH is higher than 7, the reciprocity of cucurbit[n=6-8]urils with some benzimidazole derivatives has not been observed by electronic absorption spectroscopy and fluorescence Spectroscopy.In the last, the recovery ratio of cucurbit[n=6-8]urils and some benzimidazole derivatives (2-benzimidazolemethanol, 2-benzimidazolepropionic acid and 2-aminoben-zimidazole (?) have been investigated by electronic absorption spectroscopy. Theexperimental results reveal that the recovery ratio is between 98 % and 105 % .The result is ideal.