Synthesis of New Alkynyl-Bridged 2,5-Disubstituted 1,3,4-Oxadiazoles

Abstract

A synthesis of new alkynyl-derived 2,5-disubstituted 1,3,4-oxadiazoles through palladium/copper-catalyzed Sonogashira cross-coupling between oxadiazole-substituted phenyl bromides and various arylacetylenes is described. Investigation of the absorption and emission spectra of the target compounds indicates emission profiles in the near-blue and blue region and high luminescence intensities. The presented approach is very convenient for the synthesis of luminescent small-molecules or precursors of other complex derivatives that are useful in the preparation of OLEDs as electron-transporting components.

Key words

2,5-disubstituted 1,3,4-oxadiazoles - palladium-catalyzed Sonogashira reaction - cross-coupling - ethynyl-bridged compounds - electron-deficient heterocycles

• References

• 1 These authors contributed equally to this work.
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