Executive Summary : | The performance of optoelectronic devices such as solar cells, light emitting diodes, photo sensing devices etc. relies highly on the hole transporting materials (HTMs) employed in them. Over last two decades, several small organic molecules have been designed and investigated for their hole transporting ability in various devices, due to their structural simplicity and ease of synthesis. Construction of a highly conjugated central core, combined with highly electron rich substituents at the peripherals, is one of the most applied strategies to obtain an efficient organic HTM. Fused ring heterocycles has recently been found in use as the central cores for HTMs, owing to their planar structure, enhanced conjugation and increased intermolecular – stacking. Recently, the Mentor’s group have developed and reported simple, direct and efficient protocols for synthesizing indolo[3,2-b]indoles, benzothieono[3,2-b]indoles and benzothieno[3,2-b]benzofuran derivatives and their [2,3-b] based positional isomers. HTMs having fused indole, benzothiophene and benzofuran moieties as central core have not yet been studied which might be due to the lack of facile synthetic methods for these heteroacene motifs. Based on these methodologies developed, we herein propose the design and synthesis of small organic molecule based HTMs having the above mentioned heteroacenes as the central core. |