Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, IL, USA.
Department of Chemical & Biological Engineering, Northwestern University, Evanston, IL, USA.
Angew Chem Int Ed Engl. 2018 Apr 3;57(15):3985-3989. doi: 10.1002/anie.201800230. Epub 2018 Mar 7.
DNA G-quadruplex structures were recently discovered to provide reliable scaffolding for two-dimensional organic frameworks due to the strong hydrogen-bonding ability of guanine. Herein, 2,7-diaryl pyrene building blocks with high HOMO energies and large optical gaps are incorporated into G-quadruplex organic frameworks. The adjustable substitution on the aryl groups provides an opportunity to elucidate the framework formation mechanism; molecular non-planarity is found to be beneficial for restricting interlayer slippage, and the framework crystallinity is highest when intermolecular interaction and non-planarity strike a fine balance. When guanine-functionalized pyrenes are co-crystallized with naphthalene diimide, charge-transfer (CT) complexes are obtained. The photophysical properties of the pyrene-only and CT frameworks are characterized by UV/Vis and steady-state and time-resolved photoluminescence spectroscopies, and by EPR spectroscopy for the CT complex frameworks.
DNA 四链体结构由于鸟嘌呤具有很强的氢键结合能力，最近被发现可为二维有机框架提供可靠的支架。在此，将具有高 HOMO 能量和大光学带隙的 2,7-二芳基芘砌块纳入 G-四链体有机框架中。芳基上的可调节取代基为阐明框架形成机制提供了机会；分子的非平面性有利于限制层间滑移，当分子间相互作用和非平面性达到精细平衡时，框架结晶度最高。当鸟嘌呤功能化的芘与萘二酰亚胺共结晶时，会得到电荷转移（CT）配合物。通过紫外可见光谱、稳态和时间分辨荧光光谱以及 CT 配合物框架的 EPR 光谱对仅含芘和 CT 框架的光物理性质进行了表征。
