Murphy Veronica L, Farfan Camille, Kahr Bart
Department of Chemistry and Molecular Design Institute, New York University, New York City, New York, USA.
Department of Advanced Science and Engineering, Waseda University, Tokyo, Japan.
Chirality. 2018 Apr;30(4):325-331. doi: 10.1002/chir.22817. Epub 2018 Jan 9.
The anisotropy of the optical activity of cyclo[18]carbon (C ), fully hydrogenated C (C H ), and 26 hydrogenated compounds of intermediate composition, C H , n = 1,2…17, were computed. These compounds were selected because they resemble loops of wire. The maximum gyration for acetylenic and cumulenic subgroups of compounds was linearly proportional to the product of the geometric area over which the charge can circulate, multiplied by the largest separation between carbon atoms on opposing sides of the loops. These geometric quantities can be likened to transition magnetic dipole moments and transition electric dipole moments, respectively, that can be generated in electronic excitations and which contribute in the main to nonresonant optical activity. The correlation between a computed geometric product of distance and area, and a quantum chemical property, establishes that chiroptical structure-activity relationships can be well established for judiciously chosen series of comparatively large compounds.
计算了环[18]碳（C₁₈）、全氢化的C₁₈（C₁₈H₁₈）以及26种中间组成的氢化化合物C₁₈Hₙ（n = 1,2…17）的旋光性各向异性。选择这些化合物是因为它们类似于金属丝环。化合物中炔属和累积烯属亚基团的最大回转与电荷能够循环的几何面积的乘积成正比，该乘积再乘以环相对两侧碳原子之间的最大间距。这些几何量可分别类比为在电子激发中产生的跃迁磁偶极矩和跃迁电偶极矩，它们主要对非共振旋光性有贡献。计算得到的距离与面积的几何乘积与量子化学性质之间的相关性表明，对于经过审慎选择的一系列相对较大的化合物，可以很好地建立手性光学结构 - 活性关系。
