Hole-transporting materials based on thiophene-fused arenes from sulfur-mediated thienannulations

Dithienonaphthalene and dithienochrysene derivatives that bear diarylaminophenyl groups were prepared in two steps from commercially available compounds via a Sonogashira coupling, followed by a simple sulfur-mediated thienannulation. Owing to their relatively narrow HOMO–LUMO gaps, the thus obtained compounds showed bathochromically shifted UV-Vis absorption and fluorescence spectra with higher quantum yields compared to the molecules without the diarylaminophenyl groups. Moreover, the suitable energy levels of their HOMOs and reversible redox properties permit applications for these compounds in hole-transporting layers in perovskite solar cells.