1,3,4-Oxadiazoles as luminescent materials for organic light emitting diodes via cross-coupling reactions

Highly efficient materials for the fabrication of OLEDs have been extensively investigated in terms of properties and convenient synthetic procedures. 2,5-Diaryl-1,3,4-oxadiazoles were found to display suitable structural features in order to act as good electron-transporters, and numerous research groups have focused on the synthesis of various small-molecules and polymers bearing this heterocyclic moiety. Characterisation of their optical and electronic properties indicated the oxadiazole derivatives as good candidates for the fabrication of electroluminescent devices. Chemical synthesis of compounds containing a variety of heterocyclic cores and functional organic groups has witnessed a tremendous evolution concomitant with the development of metal-catalysed cross-coupling reactions. This new approach to create molecular diversity was also observed in the field of oxadiazoles, in an attempt to prepare complex molecules whose structural particularities were able to furnish the properties required for the fabrication of functional materials. Herein, we describe a collection of literature studies that refer to 1,3,4-oxadiazole-based small-molecules and polymers that have found applications as materials for OLEDs, combined with their synthetic accesibility involving, as key step(s), cross-coupling reactions.