Physical Sciences and Mathematics Commons^™

The Synthesis Of Symmetric Polycyclic Aromatic Hydrocarbons And The Mesomorphic Properties Of Their Brominated Derivatives, Vanessa Bellemore

Theses and Dissertations (Comprehensive)

In this thesis, the synthesis of a series of brominated alkoxy-substituted trinaphthylenes was developed using a nickel-mediated Yamamoto coupling as the main step. Characterization of these compounds led to the discovery of a new set of broad range liquid crystals. They were found to undergo higher order transitions (i.e. glass phases/soft crystals/liquid crystal) via DSC, and also to decompose before reaching an isotropic liquid, as verified via thermogravimetric analysis. Polarized optical microscopy showed a texture characteristic of a columnar hexagonal mesophase. In addition, the aggregation in solution was studied using concentration dependent NMR studies, and the brominated-derivatives were determined to …