Construction of a Metal-Free Electron Spin System by Encapsulation of an NO Molecule Inside an Open-Cage Fullerene C60 Derivative
Construction of a Metal-Free Electron Spin System by Encapsulation of an NO Molecule Inside an Open-Cage Fullerene C60 Derivative
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DOI：
10.1002/anie.201807823
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发表时间：
2018-09-24
影响因子：
16.6
通讯作者：
Murata, Yasujiro
中科院分区：
文献类型：
--
作者：
Hasegawa, Shota;Hashikawa, Yoshifumi;Murata, Yasujiro
一种活性自由基物种，一氧化氮（NO），被封装在一个单分子的形式内的开笼富勒烯衍生物在高压条件下在固态。令人惊讶的是，尽管碳笼内存在顺磁性物质，但分子复合物显示出尖锐的（HNMR）-H-1信号。由于顺磁位移，NO的逃逸率由实验确定。在开口的边缘上构造塞子后，发现NO即使在50摄氏度下也留在笼内。粉末样品的ESR测量显示在低温下具有顺磁性。单晶X射线结构分析清楚地证明了包裹的NO分子的存在，表明笼内快速旋转。由于顺磁效应，（HNMR）-H-1化学位移显示出很大的温度依赖性。
A reactive radical species, nitric oxide (NO), was encapsulated in a unimolecular form inside an open-cage fullerene derivative under high-pressure conditions in the solid state. Surprisingly, the molecular complex showed sharp (HNMR)-H-1 signals despite the existence of the paramagnetic species inside the carbon cage. Owing to the paramagnetic shifts, the escape rate of the NO was determined experimentally. After constructing a stopper on the rim of the opening, the NO was found to stay inside the cage even at 50 degrees C. The ESR measurements of the powdery sample showed paramagnetic properties at low temperature. The single-crystal X-ray structure analysis clearly demonstrated the existence of the encapsulated NO molecule, suggesting rapid rotation inside the cage. The (HNMR)-H-1 chemical shifts displayed a large temperature dependence owing to the paramagnetic effects.