Baryshnikov G V, Valiev R R, Karaush N N, Minaev B F
Bohdan Khmelnytsky National University, Cherkassy, 18031, Ukraine.
Phys Chem Chem Phys. 2014 Aug 7;16(29):15367-74. doi: 10.1039/c4cp00860j.
A series of planar hetero[8]circulenes and their doubly charged ions are studied by the NICS and GIMIC methods to interpret the aromatic properties of these high symmetry species. In accordance with the performed calculations all studied hetero[8]circulenes are found to be nonaromatic compounds because paratropic and diatropic ring-currents are completely canceled yielding almost zero net current. In great contrast, the dicationic and dianionic hetero[8]circulenes demonstrate the predominant contribution of diatropic ring currents resulting in the total aromatic character of the studied doubly charged ions. This fact allows us to predict the high stability of dianionic hetero[8]circulenes and explains the extremely high stability of dicationic species observed in the mass-spectra.
通过NICS和GIMIC方法研究了一系列平面杂[8]环烯及其双电荷离子，以解释这些高对称物种的芳香性。根据所进行的计算，发现所有研究的杂[8]环烯都是非芳香族化合物，因为同芳香性和反芳香性环电流完全抵消，产生几乎为零的净电流。形成鲜明对比的是，双阳离子和双阴离子杂[8]环烯显示出反芳香性环电流的主要贡献，导致所研究的双电荷离子具有完全的芳香性。这一事实使我们能够预测双阴离子杂[8]环烯的高稳定性，并解释了在质谱中观察到的双阳离子物种的极高稳定性。
