吡啶基咪唑[4,5-f]1,10-菲咯啉合成、表征及与瓜环作用的光谱学考察

设计合成了2个吡啶基菲咯啉衍生物2-(3-吡啶基)咪唑4,5-f]1,10-菲咯啉(G1)和2-(4-吡啶基)咪唑4,5-f]1,10-菲咯啉(G2)，通过元素分析、质谱和核磁共振氢谱对其结构进行了表征。 利用紫外吸收光谱和荧光光谱法考察了所合成化合物与六元瓜环Q6]、七元瓜环Q7]的相互作用，以及体系pH值对主-客体相互作用的影响。 在酸性条件下，Q6]、Q7]与Gl以及Q6]与G2均发生包合形成1∶1的包合物，并有荧光增敏作用；Q7]与G2作用形成1∶2包合物，且对G2有荧光猝灭作用；Q6]、Q7]与G1的包合常数分别为3.00×104和1.86×104 L/mol；Q6]、Q7]与G2的包合常数分别为1.64×104和1.01×103 L/mol。 随着体系酸性减弱，瓜环与客体作用减弱，在中性条件下，瓜环未与客体发生包合作用。

Synthesis,Characterization of Pyridylimidazo[4,5-f]1,10-phenanthroline Derivates and Spectroscopic Study Their Interaction With Cucurbit[n]urils

Two pyridyl imidazo4,5-f]1,10-phenanthroline derivates, namely 2-(3-pyridyl)-imidazo4,5-f]1,10-phenanthroline(G1) and 2-(4-pyridyl)imidazo 4,5-f]1,10-phenanthroline(G2), were synthesized and characterized by elemental analysis, 1H NMR and MS. Under various concentrations of cucurbitn]urils(Qn], n=6,7), the interaction of Qn] with G1 and G2 were studied in buffer solutions with different pH values by using UV-Vis spectroscopy and fluorescence spectrophotometry. The results revealed that cucurbitn]urils(n=6,7) form a 1∶1 complex with G1, and Q6] form a 1∶1 complex with G2 in acidic solution, fluorescent sensitizing effects of both Q6] and Q7] toward guests were determined. Under acidic solution Q7] formed a 2∶1 complex with G2, and a fluorescent quenching effect of Q7] on G2 was observed. Association constants(K) of Qn](n=6,7) with G1 were found to be 3.00×104 L/mol, 1.86×104 L/mol respectively, while those of Qn](n=6,7) with G2 are 1.64×104 L/mol and 1.01×103 L/mol respectively. With decreasing acidity of the systems, the interaction between guests and Qn](n=6,7) weakened and no interaction was observed under neutral conditions.