Physical Sciences and Mathematics Commons^™

From Persistent Radicals To Conductivity: A Structure Property Investigation In A Series Of Urea-Tethered Halogenated Triphenylamines, Muhammad Saddam Hossain

Theses and Dissertations

Triphenylamines (TPAs) are known to form persistent organic radicals either by chemical, electrochemical or photoinduced oxidation. Typically, fully para-substituted TPAs form stable radical cations while the radical cations in partially substituted systems quickly degrade. Herein, we study the effects of solid-state organization on a series of urea tethered halogenated TPAs 1 (X = H, Cl, Br, I) and compare their radical cation formation and persistence after UV-irradiation. These halogenated urea tethered TPAs were examined by single-crystal X-ray diffraction where their assembly was guided by threecentered urea hydrogen bonding interaction. As expected, all compounds form photogenerated radical cations in solution, but …

Single Crystal To Single Crystal Polymerization Of A Columnar Assembled Diacetylene Macrocycle, Weiwei Xu

Theses and Dissertations

Organic tubular materials have attracted lots of attentions for their potential applications as nanoscale fluidic transport systems, specific ion sensors, molecular sieves and confined molecular reaction containers. While conjugated polymers, due to delocalized Pi electrons, exhibit interesting solar cells and sensors applications. In this thesis, we developed a conjugated polymer which combines the attributes of conjugated polymers with tubular materials, which should have great potential to work as a sensing material.

We reproduced and scaled-up the synthesis of a polymerizable macrocycle 1 that contains two rigidly separated diacetylene units. We found that, through hydrogen bonding, 1 can assemble into columnar …