Syntheses, Characterizations, and Applications of Heli-viologens and Heli-twisted-acenes

本课题由化学系化学结构与动力学机制B项目资助，由爱德华·L.怀俄明州大学化学系的Clennan和Caleb Hill正在开发由芳香环的螺旋和线性结构域组成的混合多环芳烃。 这些化合物具有不可重叠的镜像，并且预期发射圆偏振光。 我们的目标是利用这些分子的这些和其他新颖的光电特性来构建圆偏振光发光二极管和其他光电器件。 这些器件在液晶显示器、立体三维显示器和信息存储方面具有巨大的潜力。 该项目还为所有教育水平的科学家提供有机合成、电子物理表征、计算化学和光电器件构造方面的培训。 调查结果将广泛传播，并将成为怀俄明州所有社区学院外联工作的一个重要特点。 更技术性地说，这些分子的螺旋烯主链提供了一个扭矩，同时扭转并苯并锁成右旋或左旋扭转。合成修饰正在进行，以将并苯结构域从一个芳环扩展到五个芳环，并且苯基和氰基取代基被附加到并苯结构域，以将扭曲传播到并苯的全长。 此外，氮原子被嵌入并苯和螺旋结构域中以产生二氮杂并苯和heli-viologen类似物。 外消旋化障碍和解决的对映异构体的物理和电化学研究的测量被用来确定如何的结构和手性性质作为并苯长度和螺旋和并苯域的组合物的函数的变化。 圆偏振光发光二极管器件正在构建与合适的螺旋扭曲并苯基板，以确定其电流密度-电压-发光特性和圆偏振电致发光spectral.This奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

In this project, funded by the Chemical Structure, Dynamic & Mechanism B Program of the Chemistry Division, Professors Edward L. Clennan and Caleb Hill of the Department of Chemistry at the University of Wyoming are developing hybrid polyaromatic hydrocarbons consisting of helical and linear domains of aromatic rings. These compounds have non-superimposable mirror images and are anticipated to emit circularly polarized light. The goal is to take advantage of these and other novel optoelectronic features of these molecules to construct circularly polarized light emitting diodes and other optoelectronic devices. These devices have significant potential in liquid-crystal display, stereoscopic three-dimensional displays, and information storage. This project also provides training to scientists at all educational levels in organic synthesis, photophysical characterization, computational chemistry, and optoelectronic device construction. The results will be widely disseminated and will be a critical feature of outreach efforts to all the community colleges in the State of Wyoming. More technically, the helicene backbone of these molecules provides a torque that simultaneously twists and locks the acene into either a right- or left-handed twist. Synthetic modifications are being made to extend the acene domain from one to five aromatic rings and phenyl- and cyano-substituents are being appended to the acene domain to propagate the twist down the full length of the acene. In addition, nitrogen atoms are being embedded in both the acene and helical domains to generate diaza-acene and heli-viologen analogues. Measurements of racemization barriers and photophysical and electrochemical studies of the resolved enantiomers are being used to determine how the structures and chiroptical properties change as a function of acene length and the composition of the helical and acene domains. Circularly polarized light emitting diode devices are being constructed with suitable heli-twisted-acene substrates to determine their current density-voltage-luminescence characteristics and their circularly polarized electroluminescence spectra.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.