Abstract
Novel
t-butylcalix[4]arenes bearing several chromene molecules were synthesized, and their photochromism and metal-ion binding ability were examined with alkali and alkaline-earth metal ions. While the metal-ion binding ability of the
t-butylcalix[4]arene moiety facilitated the photoisomerization of the chromene moiety to a great extent, the chromene moiety influenced the metal-ion binding ability of the
t-butylcalix[4]arene moiety through lariat effect. Therefore, the metal-ion that induced the most facilitated photoisomerization of the chromene moiety was shifted drastically from Li
+ to Ba
2+ with the increase of the incorporated chromene number. Even without metal ions, the interaction among the chromene moieties derived from the cone-conformation of the
t-butylcalix[4]arene moiety also facilitated the photoisomerization.
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