Department of Chemistry, Graduate School of Science, Nagoya University, Furo, Chikusa, Nagoya 464-8602, Japan.
Angew Chem Int Ed Engl. 2012 Jul 27;51(31):7762-6. doi: 10.1002/anie.201204050. Epub 2012 Jun 22.
Give and take: The introduction of NHC-borane moieties to thiophene-based π skeletons endows a zwitterionic character, which makes the π system electron-donating, while the NHC ring acts as an electron-accepting moiety. The NHC-borane-substituted thiophene underwent a clean photoisomerization with a drastic color change, however, the expanded bithiophene derivatives were inert to this photoreaction, showed low oxidation potentials, and formed a slipped π-stacked array in the crystal.
将 NHC-硼烷部分引入噻吩基 π 骨架赋予了两性离子特征，使 π 体系具有供电子性，而 NHC 环则作为受电子部分。NHC-硼烷取代的噻吩发生了干净的光异构化，伴随着剧烈的颜色变化，然而，扩展的联噻吩衍生物对此光反应惰性，表现出低氧化电位，并在晶体中形成了滑动的π堆积排列。
