Wurster’s Blue-type Cation Radicals Framed in a 5,10-Dihydrobenzo[<i>a</i>]indolo[2,3-<i>c</i>]carbazole (BIC) Skeleton: Dual Electrochromism with Drastic Changes in UV/Vis/NIR and Fluorescence
作者:Takanori Suzuki、Yuto Sakano、Yusuke Tokimizu、Youhei Miura、Ryo Katoono、Kenshu Fujiwara、Naoki Yoshioka、Nobutaka Fujii、Hiroaki Ohno
DOI:10.1002/asia.201402394
日期:2014.7
one‐electron oxidation to the corresponding Wurster’s Blue (WB)‐type species that exhibits NIR absorptions up to λ=1200 nm. In the case of the N,N′‐dimethyl derivative, cation radical 1 c+. is stable enough to be isolated as a salt and X‐ray analysis indicated paraquinoid‐type bond alternation in the WB core unit, whereas the bond lengths in the peripheral benzene rings are identical to those in the neutral
通过金(I)催化环化制备了采用平面圆盘形几何形状的供电子二氢苯并吲哚并咔唑(BIC)1 a – c作为关键步骤。由于框架中存在1,4-苯二胺(PD)部分,它们经历了可逆的单电子氧化,变成了相应的Wurster's Blue(WB)型物质,在λ = 1200 nm处显示出NIR吸收。对于N,N'-二甲基衍生物,阳离子自由基为1 c +。X射线分析表明WB核心单元中的对醌型键交替,因此其稳定性足以分离成盐,而X射线分析表明其外围苯环中的键长与中性供体中的键长相同。在电化学互变中,氧化还原对为1 a – c和1 a – c +。表现出在紫外/可见/近红外区域的电致变色反应,这是伴随着在荧光光谱的急剧变化,因为只有中性供体1 - ç是高发射(Φ ˚F:0.7-0.8)。