Planarization of a bowl-shaped molecule by triple-decker stacking
Planarization of a bowl-shaped molecule by triple-decker stacking
复制标题
通过三层堆叠平坦化碗形分子
DOI：
10.1016/j.xcrp.2022.101045
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发表时间：
2022
影响因子：
8.9
通讯作者：
Shinokubo Hiroshi
中科院分区：
文献类型：
--
作者：
Kawashima Hiroyuki;Fukui Norihito;Phung Quan Manh;Yanai Takeshi;Shinokubo Hiroshi
碗状π共轭分子通常通过平面化过渡态（TS）进行碗状反转运动，平面化过渡态是两个最小碗状结构之间的反应坐标上的最高能态。孤立这种扁平化的国家是一项挑战。在这里，我们报道了一种反芳香卟啉的铂（II）配合物，诺克罗，在溶液中呈碗状构象，但在固体中可以变成平面。在结晶状态下，去光咯铂（II）配合物形成三层堆叠结构，其中平面化的去光咯被稳定地夹在两个碗状的去光咯之间。该平面构象对应于碗状分子动态碗到碗反转运动中的TS结构。详细的理论研究表明，取代基之间的色散力和反芳香大环配体产生的增强的Pt-Pt相互作用稳定了本不稳定的平面构象。
A bowl-shaped π-conjugated molecule typically undergoes bowl-inversion motion via a planarized transition state (TS), the highest-energy state along the reaction coordinate between two minimum bowl structures. Isolation of such planarized state has been challenging. Here, we report that a platinum(II) complex of antiaromatic porphyrin, norcorrole, adopts bowl-shaped conformation in solution but can become planar in solid. In the crystalline state, the norcorrole Pt(II) complex forms triple-decker stacking structures, in which the planarized norcorrole is stabilized and sandwiched between two bowl-shaped norcorroles. The planar conformation corresponds to the TS structure in the dynamic bowl-to-bowl inversion motion of the bowl-shaped molecule. Detailed theoretical studies have revealed that the intrinsically unstable planar conformation is stabilized by the dispersion force among the substituents and enhanced Pt–Pt interactions created by the antiaromatic macrocyclic ligand.