Comparison of Linear and Cross-Conjugation from Rates of Vinylheptafulvene Ring-Closure
作者:Kasper Fjelbye、Trine Nørgaard Christensen、Martyn Jevric、Søren Lindbaek Broman、Anne Ugleholdt Petersen、Anders Kadziola、Mogens Brøndsted Nielsen
DOI:10.1002/ejoc.201403117
日期:2014.12
The concept of cross-conjugation has in recent years attracted increasing interest in materials science as well as in the field of molecular electronics as a means to tune the optical properties and molecular conductance of nanoscale devices. In this paper we show how the rate of an electrocyclic reaction, the conversion of vinylheptafulvene (VHF) into dihydroazulene (DHA), is influenced by an electron-withdrawing
近年来,交叉共轭的概念在材料科学以及分子电子学领域引起了越来越多的兴趣,作为调节纳米级器件的光学特性和分子电导的手段。在本文中,我们展示了电环反应的速率,即乙烯基七富烯 (VHF) 转化为二氢芴烯 (DHA) 的速率如何受到通过交叉共轭或线性 π- 与 VHF 分离的吸电子对硝基苯基基团的影响共轭桥接单元。通过金属催化偶联反应制备了一系列具有乙炔、1,1-和 1,2-二乙炔乙烯和 1,3-丁二炔桥的 DHA/VHF 分子。不同共轭间隔物对 VHF 向 DHA 转化动力学的影响通过 UV/Vis 吸收光谱法通过监测 VHF 吸收的衰减来检查。发现交叉共轭二乙炔间隔物相对于线性共轭间隔物增加了 VHF 的半衰期。