Conjugated polymers are a class of materials receiving significant interest due to their unique combination of optical and electronic properties found in inorganics with the flexibility and processability of traditional organic plastics. These materials have become popular in application to electronic devices such as organic photovoltaics (OPVs), organic light-emitting diodes (OLEDs), sensors, electrochromics and field effect transistors (FETs). As the energetic gap between frontier orbitals, the band gap (Eg) is largely responsible for the energetic transitions of these materials and thus tuning of this parameter is of great interest. A popular method to reducing Eg is through the use of fused ring systems such as thieno[3,4-b]pyrazines (TPs). These TP-based materials have been previously applied to solar cells. However, all exhibited limited efficiency (<5% PCE). In an effort to improve the efficacy of TPs in electronic devices, the scope of available TP materials was expanded in an effort to study the effect of changing both side chain and comonomer has on the material properties. In an effort to study the effect of side chains Rasmussen and coworkers introduced a new method in 2008 toward synthesis of 2nd generation TPs with expanded electronic tuning. To further develop this work, preparation of new electron-withdrawing TPs were generated. Application of 1st and 2nd generation TPs in the production of homopolymeric and copolymeric materials was performed, along with characterization of their optical and electronic properties. Select materials with altering side chain and comonomeric unit were then applied to OPV devices and efficiencies were evaluated based on the changed parameter.