Cucurbituril - Metal Complexes Of The Ultra Molecular System Investigated Catalytic Properties Of The Bnpp Hydrolysis

The complex, [Cu(N,N'-Bis (2-hydroxy-benzyl)(en))·2H₂O], has been synthesized and characterized, and the interaction of cucurbit[6]uril with the above complex guest (g) has been investigated by using ultraviolet spectrophotometry, infrared spectroscopy and thermogravimetry analysis . The experimental results revealed that the interaction of Q[6] and guest has been in the ratio of 2:1. Also the host-guest system of Q[6]-g can catalyze BNPP hydrolysis, and the hydrolysis kinetics in presence of Q[6]-g is far more fast than in absence of catalysts,its rate constant is 2.34×10^-4 S^-1The interaction of cucurbit[8]uril host with [Co(N₃) (N₂)C1][ZnCl₄] guests such as [Co(2,3-tri)(cmen)Cl][ZnCl₄] (g1), [Co(3,3-tri) (cmen)Cl][ZnCl₄] (g2), [Co(2,3-tri)(amp)Cl][ZnCl₄] (g3), [Co(3,3-tri)(amp)Cl][ZnCl₄] (g4) have been investigated by ultraviolet absorption spectroscopy, infrared spectroscopy. The experimental results of molar ratio and job methods revealed that the interactions of Q[8] and guests have been in the ratio of 1:1 respectively, and the assiocation constant have been found in the range from 10⁴ L·mol^-1 to 10⁷ L·mol^-1. Stabilities of cucurbit[8]uril with [Co(N₃) (N₂)Cl][ZnCl₄] have been effected by the structures of the ligands of N₃ and N₂, more the number of carbon in N₃ is, assiocation constant is larger, however, the group of pyridine resulted in the weaker Stability. Moreover, the host-guest system of Q[8]-gn can catalyze BNPP hydrolysis, and the hydrolysis kinetics in presence of Q[8]-gn is far more fast than in absence of supramolecular catalyst.