Design-Structure-Property Relationships of Purine-Based Copolymers and Chromophores

Understanding the relationship between monomer design and polymer properties is imperative for developing polymeric systems that can find applicability in targeted technologies. Purines have been extensively studied across many scientific disciplines and are useful due to the diverse properties they possess, which is due in part to the broad scope of precise synthetic transformations that are used to tailor their properties. The overarching goal of my dissertation involves developing the synthesis of “poly(purine)s” and investigating the effect of purine monomer design on polymer properties. In this vein, poly(purine)s and purine-based donor-acceptor small-molecules are synthesized via Stille cross-coupling reactions with a key variation being the nature of the π-conjugated comonomers and substitution pattern of the purine monomer. Investigations of thermal and photophysical properties reveal a dependence on purinyl monomer design and comonomer type on properties such as glass transition temperature (thermal behavior) and charge-transfer character (photophysical properties). The work described herein presents the first example of poly(purine)s in which a purine is directly incorporated into a polymer backbone, systematic design of donor-acceptor purine-based chromophores with tunable thermal and photophysical properties, and the first example of the synthesis of fully conjugated donor-acceptor poly(purine)s. My findings demonstrate the viability of purines in metal-catalyzed reactions and the potential to tailor optoelectronic properties of purine-based polymers and small molecules. This work lays the foundation for further development of purine-based π-conjugated systems, including poly(purine)s suitable for high performance organic electronic devices.