一对含有苯甲醛基修饰的杯芳烃异构体的晶体结构以及它们与铽离子配位的光物理性质

Two calix[4]arene isomers with benzaldehyde moieties, i.e., 5,11,17,23-tetra-tert-butyl-25,27-bis[2-(o-formyl-phenoxy)ethoxy]-26,28-dihydroxycalix[4]arene (3) and 5,11,17,23-tetra-tert-butyl-25,27-bis[2-(p-formylphenoxy)-ethoxy]-26,28-dihydroxycalix[4]arene (4), were synthesized according to a newly designed route in high yields, and their crystal structures have been determined by X-ray crystallographic study. The photophysical behavior on complexation of calix[4]arene derivatives 3 and 4 with terbium(Ⅲ) nitrate was investigated in anhydrous acetonitrile at 25℃ by UV-Vis and fluorescence spectroscopies. The crystallographic structure of 3 indicated that the eight oxygen atoms formed a preorganized ionophoric cavity due to intramolecular π-π stacking, which could encapsulate lanthanide ions tightly. In sharp contrast, the compound 4 formed a linear array by intermolecular π-π stacking, hence the oxygen atoms of pendant arms could not coordinate with metal ions, giving a poor binding ability to Tb^3 . The absorption spectra of 3 with Tb^3 showed clearly a new broad intense absorption at 385nm. Interestingly, the narrow emission line spectrum has also been observed for compound 3 with Tb^3 , and the results obtained were discussed from the viewpoint of energy transfer mechanism between host structures and the properties of lanthanide ions.

Crystal Structures of Two Calix[4]arene Isomers with Benzaldehyde Moiety and Their Photophysical Properties with Terbium(III) Ions

Two calix[4]arene isomers with benzaldehyde moieties, i.e., 5,11,17,23‐tetra‐tert‐butyl‐25,27‐bis[2‐(o‐formyl‐phenoxy)ethoxy]‐26,28‐dihydroxycalix[4]arene ( 3 ) and 5,11,17,23‐tetra‐tert‐butyl‐25,27‐bis[2‐(p‐formylphenoxy)‐ ethoxy]‐26,28‐dihydroxycalix[4]arene ( 4 ), were synthesized according to a newly designed route in high yields, and their crystal structures have been determined by X‐ray crystallographic study. The photophysical behavior on com‐plexation of calix[4]arene derivatives 3 and 4 with terbium(III) nitrate was investigated in anhydrous acetonitrile at 25°C by UV‐Vis and fluorescence spectroscopies. The crystallographic structure of 3 indicated that the eight oxygen atoms formed a preorganized ionophoric cavity due to intramolecular π‐π stacking, which could encapsulate lanthanide ions tightly. In sharp contrast, the compound 4 formed a linear array by intermolecular π‐π stacking, hence the oxygen atoms of pendant arms could not coordinate with metal ions, giving a poor binding ability to Tb³⁺. The absorption spectra of 3 with Tb³⁺ showed clearly a new broad intense absorption at 385 nm. Interestingly, the narrow emission line spectrum has also been observed for compound 3 with Tb³⁺, and the results obtained were discussed from the viewpoint of energy transfer mechanism between host structures and the properties of lanthanide ions.