This Thesis deals with the design, synthesis and study of properties of novel 4,5-diazafluorene based material for application in electronic devices. Organic conjugated polymers with semiconducting properties offer many exciting prospects in material science and nanoelectronics and attract tremendous interest from both academia and hi-tech industry. Over the last decade, polyfluorenes (PF) have emerged as leading electroluminescent materials with bright blue emission, good thermal and electrochemical stability, high charge mobility and easily tunable properties through chemical modifications and co-polymerisations. 4,5-diazafluorene is topologically similar to fluorene, however, due to presence of electron deficient nitrogen atoms it possess much lower LUMO energy level.
Moreover, the two nitrogen atoms of 4,5-diazafluorene provides the binding site to form metal complexes similar to well-known ligands 1,10-phenanthroline and 2,2'-bipyridine. These advantages makes 4,5-diazafluorene an attractive object for design of novel electron deficient conjugated oligomers, polymers and metal complexes for optoelectronics applications such as organic light-emitting diodes (OLED), light-emitting electrochemical cells (LEC), photovoltaics (OPV), field-effect transistors (FET) and sensors. The Thesis is presented in the form of five chapters. In the first chapter, a brief introduction about organic electronic is described. Chapter 2 deals with the development of synthetic method for key starting material 2,7-dibromo-4,5-diazafluorene. Chapter 3 exclusively discussed 4,5-diazafluorene based iridium complexes for light emitting electrochemical cells. In chapters 4 and 5, 4,5-diazafluorene based oligomers and polymers are discussed, respectively.