Rashvand Avei Mehdi, Etezadi Sedigheh, Captain Burjor, Kaifer Angel E
Department of Chemistry, University of Miami, Coral Gables, FL, 33124, USA.
Commun Chem. 2020 Aug 13;3(1):117. doi: 10.1038/s42004-020-00363-4.
While oxidized pillar[5]arenes with 1-5 benzoquinone units are known, very few examples of oxidized pillar[6]arenes have been reported. We describe here the synthesis, characterization and electrochemical behavior of a series of macrocyclic hosts prepared by the stepwise oxidation of 1,4-diethoxypillar[6]arene, resulting in high-yield and high-purity isolation of two constitutional isomers for each macrocycle, in which two, three or four 1,4-diethoxybenzene units are replaced by benzoquinone residues. A careful structural comparison with their counterparts in the pillar[5]arene framework indicates that the geometries of the macrocycles are better described as non-Euclidean hyperbolic hexagons and elliptic pentagons, respectively. A comprehensive computational study to determine anisotropic induced current density (ACID) allows us to visualize and quantify through-space and through-bond communication pathways along the macrocyclic belt. Experimental and simulated voltammetric data, as well as UV-vis spectra, of the new macrocycles afford insights into the various electronic communication pathways in these compounds.
虽然含有1 - 5个对苯醌单元的氧化柱[5]芳烃是已知的，但氧化柱[6]芳烃的实例报道却很少。我们在此描述了一系列大环主体的合成、表征及电化学行为，这些大环主体是通过1,4 - 二乙氧基柱[6]芳烃的逐步氧化制备的，每个大环都能高产率、高纯度地分离出两种构造异构体，其中两个、三个或四个1,4 - 二乙氧基苯单元被对苯醌残基取代。与柱[5]芳烃骨架中的对应物进行仔细的结构比较表明，大环的几何形状分别更好地描述为非欧几里得双曲线六边形和椭圆五边形。通过确定各向异性感应电流密度（ACID）的全面计算研究，使我们能够沿着大环带可视化并量化空间和键间的通信途径。新大环的实验和模拟伏安数据以及紫外可见光谱，为了解这些化合物中的各种电子通信途径提供了深入见解。
