葫芦[7]脲对新型偶氮染料的组装及其pH调控研究

Study of New Azo Dyestuff Assembled with Cucurbit [7]uril and Their pH-Controlled

研究了一种新型偶氮客体染料分子在水溶液中通过非共价键作用与葫芦脲组装成准轮烷的过程以及改变体系pH对准轮烷各项性能的影响。紫外-可见滴定表明,构建的准轮烷随着体系pH的改变其λmax发生蓝移或者红移。通过荧光滴定拟合曲线确定主客体均以摩尔比1∶1进行包结。随着pH值的来回变换,主体对客体分子的两个分支上的包结是一个可逆过程。因此本文得到了一类基于CB[7]可以直接观察颜色变化的pH调控准轮烷开关。

Assembling CB [ 7 ] with a new azo dyestuff Va into a pseudorotaxane Va CB [ 7] in aqueous solution by noncovalent bond- ing, and effect of pH on characteristics of the pseudorotaxane were studied. Results of UV/vis titration showed that λmax of the pseudoro- taxane had hypsochromic shift or bathochromic shift with pH change. Fitting curves results of fluorescent titration indicated constructing 1 ： 1 complexes between compound CB[7] and a guest dye Va. As the pH change back and forth, host to the guest of molecules on the two branches of inclusion was a reversible process. So, a pH controlled reversible pseudorotaxane Va CB [ 7 ] with color change was constructed.