The Tetracyanoquinodimethane Motif in Overcrowded Bistricyclic Aromatic Enes: Avoiding Thermochromism
作者:Sergey Pogodin、Michal Rachel Suissa、Amalia Levy、Shmuel Cohen、Israel Agranat
DOI:10.1002/ejoc.200701125
日期:2008.6
[10-[10-oxo-9(10H)-anthracenylidene]-9(10H)-anthracenylidene)]propanedinitrile(8) were synthesized by a condensation of bianthrone (2) with malononitrile in the presence of TiCl4 and pyridine. The crystal and molecular structure of 7 were determined. It crystallizes in two polymorphic forms, belonging to the space groups P21/c and P21/n. DFT calculations of 7 and 8 show that the overcrowding due to introducing
过度拥挤的双三环芳族烯 (BAE) [10-[10-(二氰基亚甲基)-9(10H)-蒽基]-9(10H)-蒽基]丙二腈 (7) 和 [10-[10-oxo-9(10H) -蒽基]-9(10H)-蒽基)]丙二腈(8)是通过联蒽酮(2)与丙二腈在TiCl4和吡啶存在下的缩合合成的。确定了7的晶体和分子结构。它以两种多晶型形式结晶,属于空间群 P21/c 和 P21/n。7 和 8 的 DFT 计算表明,由于在 10 和 10' 位置引入二氰基亚甲基取代基导致的过度拥挤在扭曲构象中更为明显,从而降低了它们的稳定性。BAE 7 和 8 中反折叠和最低扭曲构象之间的焓差分别为 61.3 和 42.3 kJ/mol。根据理论,BAE 7 和 8 不表现出热致变色行为。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)