Electrical properties and synthesis of tetracene and rubrene derivatives

Chapter 1. Presented herein is the synthetic approach for the assembling of the tetracene core via a Friedel-Crafs reaction. Development of this method allowed us to synthesize different halogenated tetracene derivatives. New coupling conditions have been developed for the Kumada-Corriu cross-coupling reaction. Cross-coupling could often be achieved at room temperature for chlorinated acenes with low catalyst loadings. These conditions were successful even with sterically crowded substrates and can be used to prepare "twisted acenes" such as octamethylnaphthalene. Several synthesized tetracene derivatives have been employed into device fabrication. Organic field effect transistor (OFET) measurements for single crystal of tetracene tetrachloride showed semiconductor behavior of examined material. Studies of the physical and chemical properties of this compound resulted in important conclusions about behavior of this tetracene-based materials in OFETs applications.;Chapter 2. In this chapter discovery of unexpected indene formation during cross-coupling reaction is reported. Mechanism of the formation of this material has been studied using forward synthesis of intermediates. Several different indene derivatives have been synthesized using developed conditions. Indene based materials appeared to be an interesting compound for solar cell applications, and their electrical properties as donors in solar cells has been studied. Measurements for the solar cells are reported and dependence between thickness of the donor and power conversion efficiency is discussed.;Chapter 3. Presented herein are studies toward finding new approaches for synthesis of the rubrene derivatives. Our approach involves two different pathways for the introduction of the rubrene functionality starting from the same simple and easily prepared substrate. This allows choosing the reaction conditions depending on the functionality of the molecule and the reactivity of the substituents. Rubrene itself have been synthesized as a proof of concept as well as several other rubrene derivatives.