Defying strain in the synthesis of an electroactive bilayer helicene
作者:Margarita Milton、Nathaniel J. Schuster、Daniel W. Paley、Raúl Hernández Sánchez、Fay Ng、Michael L. Steigerwald、Colin Nuckolls
DOI:10.1039/c8sc04216k
日期:——
We report the synthesis of a bilayer chiral nanographene incorporating a [7]helicene scaffold and two perylene-diimide (PDI) subunits. Twofold visible-light-induced oxidative cyclization of a phenanthrene framework selects for the desired PDI-helicene, despite the immense strain that distinguishes this helicene from two other accessible isomers. This strain arises from the extensive intramolecular
BN-Embedded Cycloarenes: One-Pot Borylation Synthesis, Photoelectric Properties, and Application in Perovskite Solar Cells
作者:Junting Wang、Aibin Zheng、Yuren Xiang、Junzhi Liu
DOI:10.1021/jacs.3c04190
日期:2023.7.12
Incorporating heteroatoms, such as nitrogen, oxygen, and/or sulfur atoms, into cycloarenes can effectively regulate their molecular geometries and (opto)electronic properties. However, the rarity of cycloarenes and heterocycloarenes limits the further exploitation of their applications. Herein, we designed and synthesized the first examples of boron and nitrogen (BN)-doped cycloarenes (BN-C1 and BN-C2)
将氮、氧和/或硫原子等杂原子掺入环芳烃中可以有效调节其分子几何形状和(光)电子性质。然而,环芳烃和杂环芳烃的稀有性限制了其应用的进一步开发。在此,我们通过亚胺基大环化合物的一锅分子内亲电硼基化设计并合成了硼和氮(BN)掺杂的环芳烃(BN-C1和BN-C2 )的第一个例子。BN-C2采用碗形构象,而BN-C1具有平面几何形状。因此,通过替换BN-C1中的两个六边形,BN-C2的溶解度得到显着提高由于产生远离平面的扭曲,具有两个 N 形五边形。对杂环芳烃BN-C1和BN-C2进行了各种实验和理论计算,证明引入的 BN 键减少了 1,2-氮杂硼烷单元及其相邻苯环的芳香性,但保留了原始凯库烯的主要芳香特性。重要的是,当引入两个额外的富电子氮原子时,与BN-C1相比, BN-C2的最高占据分子轨道能级被精心提升。因此,BN-C2的能级排列阳极和钙钛矿层的功函数是合适的。因此,首次探索杂环芳烃(BN-
Iridium-catalyzed borylation of phenacenes with bis(pinacolato)diboron proceeds either in an edge-selective manner for diborylation or an edge/side-selective manner for tetraborylation. Multiply borylated [n]phenacenes (n = 3-5) were synthesized in reasonable yields. (C) 2011 Elsevier Ltd. All rights reserved.
Fluorescence Enhancement of Aromatic Macrocycles by Lowering Excited Singlet State Energies
processes. A high energy barrier along the S0/S1 internal conversion path to reach the minimum energy conical intersection was necessary to hamper a nonradiative process, and with the transition state energy level of the excited singlet state being insensitive to macrocyclic structures, a low energy level of excited singlet states (S1MIN) was required to facilitate efficient fluorescence.