Triple and Quadruple Triptycene Gears in Rigid Macrocyclic Frameworks
Triple and Quadruple Triptycene Gears in Rigid Macrocyclic Frameworks
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DOI：
10.1002/ejoc.201701067
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发表时间：
2017-10
影响因子：
2.8
通讯作者：
S. Toyota;Kenta Kawahata;K. Sugahara;K. Wakamatsu;T. Iwanaga
中科院分区：
文献类型：
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作者：
S. Toyota;Kenta Kawahata;K. Sugahara;K. Wakamatsu;T. Iwanaga
本文研究了由三个或四个9，10-三蝶环单元和1，2-亚苯基、亚乙炔基骨架组成的大环化合物的结构和动力学行为。这些化合物是由9，10-二乙炔基三蝶烯衍生物和二碘苯通过重复的Sonogashira偶联反应合成的。DFT计算表明，三蝶烯单元中的苯环在内部区域相互啮合，导致通过π···π和CH···π接触的整体吸引相互作用，而不管三聚体中的显著分子变形。对称的1H NMR信号图案意味着齿轮部分的旋转即使在低温下也迅速发生。我们通过DFT计算分析了动力学行为的转动机制，其中转动是部分或完全相关的。估计的旋转障碍是非常低的三聚体和四聚体，分别在22.5和3.9千焦mol-1。
The structures and the dynamic behavior of macrocyclic compounds consisting of three or four 9,10-triptycyl units and 1,2-phenylene and ethynylene frameworks were studied as a multiple-gear system. These compounds were synthesized from 9,10-diethynyltriptycene derivatives and a diiodobenzene by repeated Sonogashira coupling reactions. DFT calculations revealed that the benzene rings in the triptycene units meshed with each other in the inside region, leading to overall attractive interactions via π···π and CH···π contacts, regardless of the significant molecular deformations in the trimer. The symmetric 1H NMR signal pattern means that the rotation of gear moieties takes place rapidly even at a low temperature. We analyzed the rotational mechanisms of the dynamic behavior by DFT calculations, where the rotation was partly or fully correlated. The estimated rotational barriers were very low at 22.5 and 3.9 kJ mol-1 for the trimer and the tetramer, respectively.