Straightforward and regiospecific synthesis of 1,3,5,7-tetra-arylated acene bearing different aryl groups

Multiple arylated acene derivatives play an important role in organic electronic materials. In this study, we developed a protocol for the synthesis of 1,3,5,7-tetra-arylated acenes by combining conventional cross-coupling and unique regio-selective cross-dehydrogenative coupling (CDC) reactions. 1,3,5,7-Tetra-arylated acene derivatives with different aryl groups were synthesised by first introducing aryl groups at the 1,5-positions via conventional cross-coupling reactions and then selectively introducing pentafluorophenyl groups at the sterically favourable 3,7-positions via CDC reactions. The CDC reactions proceeded smoothly on the substrates with moderately electron-donating substituents at the 1,5-positions. The crystal structure and basic physical properties of the products were elucidated, and one of 1,3,5,7-tetra-arylated anthracenes was found to function as a light-emitting material in organic light-emitting diodes.