Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, USA.
J Am Chem Soc. 2011 Aug 24;133(33):12918-21. doi: 10.1021/ja203509s. Epub 2011 Jul 27.
Comparisons are made of the calculated optical rotation tensors of C(2v)-symmetric, polyaromatic hydrocarbons and their [5]helicene, [6]helicene, and [7]helicene isomers. Seven ∩-shaped, planar compounds had, in each case, larger computed tensor elements than the chiral helicenes. Merely obviating the condition of solution averaging wholly changes expectations of the magnitudes and etiologies of optical activity. Symmetries of achiral compounds facilitate semiquantitative correlations between structure and optical rotation.
对具有 C(2v)对称的多环芳烃及其[5]螺烯、[6]螺烯和[7]螺烯异构体的计算旋光张量进行了比较。在每种情况下，七个∩形、平面化合物的计算张量元素都大于手性螺烯。仅仅避免溶液平均化的条件就完全改变了对旋光活性的大小和起源的预期。非手性化合物的对称性有助于结构与旋光之间的半定量相关性。
