Barboiu Mihail, Prodi Luca, Montalti Marco, Zaccheroni Nelsi, Kyritsakas Nathalie, Lehn Jean-Marie
Laboratoire de Chimie Supramoléculaire, ISIS, Université Louis Pasteur, 8, allée Gaspard Monge, BP 70028, 67083 Strasbourg Cedex, France.
Chemistry. 2004 Jun 21;10(12):2953-9. doi: 10.1002/chem.200306045.
The terpy-derived (terpy=terpyridine) ligand 1 has an extended W shape in which the two appended photoactive pyrenyl groups are held apart. On binding of a zinc(II) ion with a terpy group, ligand 1 is converted into complex 2 whereby it adopts a U shape, thus stacking the aromatic units. This structural modification leads to a very pronounced change in photophysical properties: from a highly fluorescent free ligand to a very weakly emitting complex. The W/U structural switching can be reversibly induced by the addition of a competitive tren ligand, which binds and releases a zinc(II) ion under protonation/deprotonation cycles, thus leading to oscillations in light emission. Therefore, the present system performs periodic modulation of optical output through a nanomechanical shape-flipping motion, triggered by metal ion binding and fuelled by acid-base neutralisation energy. Overall, it represents an ion-triggered opto-mechanical supramolecular device.
基于三联吡啶衍生的（terpy = 三联吡啶）配体1呈伸展的W形，其中两个附加的光活性芘基相互分开。当锌（II）离子与一个三联吡啶基团结合时，配体1转变为配合物2，此时它呈U形，从而使芳香单元发生堆积。这种结构修饰导致光物理性质发生非常显著的变化：从高荧光性的游离配体转变为发光非常微弱的配合物。通过添加竞争性的三亚乙基四胺（tren）配体，可以可逆地诱导W/U结构转换，该配体在质子化/去质子化循环下结合并释放锌（II）离子，从而导致发光振荡。因此，本体系通过由金属离子结合触发并由酸碱中和能量提供动力的纳米机械形状翻转运动，实现了光输出的周期性调制。总体而言，它代表了一种离子触发的光机械超分子器件。
