7,7,8,8-Tetraaryl-<i>o</i>-quinodimethane Stabilized by Dibenzo Annulation: A Helical π-Electron System That Exhibits Electrochromic and Unique Chiroptical Properties
作者:Takanori Suzuki、Yuto Sakano、Tomohiro Iwai、Shinichi Iwashita、Youhei Miura、Ryo Katoono、Hidetoshi Kawai、Kenshu Fujiwara、Yasushi Tsuji、Takanori Fukushima
DOI:10.1002/chem.201203092
日期:2013.1.2
When two benzene rings are fused to a tetraaryl‐o‐quinodimethane skeleton, sterically hindered helical molecules 1 acquire a high thermodynamic stability. Because the tetraarylbutadiene subunit contains electron‐donating alkoxy groups, 1 undergo reversible two‐electron oxidation to 22+, which can be isolated as deeply colored stable salts. Intramolecular transfer of the point chirality (e.g., sec‐butyl)
当两个苯环稠合到四芳基-邻-喹二甲烷骨架上时,位阻螺旋分子1具有很高的热力学稳定性。由于四芳基丁二烯亚基包含供电子的烷氧基,因此1经历可逆的双电子氧化为2 2+,可以将其分离为深色的稳定盐。分子内芳基上的手性点(例如仲丁基)分子向分子螺旋的转移引起非对映异构体在2 b 2+和2 c 2+的优先选择,它是增强圆二色性信号的有效方法。因此,这些氧化还原对可以用作新的电按摩响应系统。X射线对2 2+离子的分析表明,二芳基甲基鎓部分存在π-π堆积相互作用,该相互作用也存在于溶液中。堆叠几何形状是手性溶胶变色反应的关键因素。