化学
对映体药物
发色团
位阻效应
螺旋烯
对映体
圆二色性
手性(物理)
光化学
结晶学
立体化学
分子
对映选择合成
有机化学
手征对称性
Nambu–Jona Lasinio模型
物理
量子力学
夸克
催化作用
作者
Bernhard Mahlmeister,Magnus Mahl,Helmut Reichelt,Kazutaka Shoyama,Matthias Stolte,Frank Würthner
摘要
Graphene nanoribbons (GNRs) have the potential for next-generation functional devices. So far, GNRs with defined stereochemistry are rarely reported in literature and their optical response is usually bound to the ultraviolet or visible spectral region, while covering the near-infrared (NIR) regime is still challenging. Herein, we report two novel quaterrylene bisimides with either one- or twofold-twisted π-backbones enabled by the steric congestion of a fourfold bay arylation leading to an end-to-end twist of up to 76°. The strong interlocking effect of the π-stacked aryl substituents introduces a rigidification of the chromophore unambiguously proven by single-crystal X-ray analysis. This leads to unexpectedly strong NIR emissions at 862 and 903 nm with quantum yields of 1.5 and 0.9%, respectively, further ensuring high solubility as well as resolvable and highly stable atropo-enantiomers. Circular dichroism spectroscopy of these enantiopure chiral compounds reveals a strong Cotton effect Δε of up to 67 M-1 cm-1 centered far in the NIR region at 849 nm.
科研通智能强力驱动
Strongly Powered by AbleSci AI