Anisotropic Contraction of a Polyaromatic Capsule and Its Cavity-Induced Compression Effect
Anisotropic Contraction of a Polyaromatic Capsule and Its Cavity-Induced Compression Effect
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DOI：
10.1021/jacs.0c02932
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发表时间：
2020-05-27
影响因子：
15
通讯作者：
Yoshizawa, Michito
中科院分区：
文献类型：
--
作者：
Kishida, Natsuki;Matsumoto, Kyosuke;Yoshizawa, Michito
通过对弯曲的多芳基配体进行简单的间位到邻位修饰，展示了球形多芳基胶囊的各向异性收缩。由此产生的胶囊由两个金属离子和四个邻位取代的配体组成，具有一个由多芳基框架完全环绕的椭球形空腔（1.1纳米×1.5纳米×1.5纳米）。一个大的平面或碗状分子（例如，卟吩或蒄）被胶囊定量结合，其中空腔诱导的压缩效应导致蒄的碗 - 碗翻转加速。温度依赖性的¹H NMR分析表明，在包封时翻转的活化能大幅降低（在318 K时，ΔG‡ = -2.8千卡/摩尔），而在先前的多芳基胶囊的球形空腔中观察到了相反的效果。
Anisotropic contraction of a spherical polyaromatic capsule was demonstrated through simple meta-to-ortho modification of the bent polyaromatic ligands. The resultant capsule, composed of two metal ions and four ortho-substituted ligands, possesses a spheroidal cavity (1.1 nm x 1.5 nm x 1.5 nm) fully encircled by a polyaromatic framework. One large planar or bowl-shaped molecule (e.g., porphine or sumanene) is quantitatively bound by the capsule, in which the cavity-induced compression effect causes the acceleration of the bowl-to-bowl inversion of sumanene. Temperature-dependent H-1 NMR analysis revealed that the activation energy of the inversion decreases greatly (Delta G(double dagger) = -2.8 kcal mol(-1) at 318 K) upon encapsulation, whereas the opposite effect was observed in the spherical cavity of the previous polyaromatic capsule.