Functionalized Tetrathienoanthracene: Enhancing π–π Interactions Through Expansion of the π-Conjugated Framework

The functionalization of tetrathienoanthracene (TTA)
with bromine
and 2-hexylthiophene moieties is described, and their influence at
both the molecular and solid-state level has been investigated. Comparative
optical and electrochemical studies indicate an increase in conjugation
for the thiophene derivative compared to the parent TTA. In the solid
state, these materials form slipped π-stack structures with
a number of close intermolecular contacts. Comparison of the two structures
reveals a more steeply inclined slipped π-stack for the thiophene
derivative resulting in a closer interplanar separation. This, coupled
with the extended molecular framework, leads to an enhanced number
of π–π interactions within the stack. The combination
of increased conjugation at the molecular level, and π-stacked
structures with strong intermolecular communication at the solid-state
level, augurs well for the use of TTA materials in optoelectronic
applications.