Abstract: Dimeric 1,3,4-oxadiazoles derivatives with flexible linkers and end-alkoxy groups, namely 1,3-bis[2-(4-alkyoxyphenyl)-1,3,4-oxidiazole-5-yl]-5-[3 or 6-(4-methoxyphenoxy) alkoxy]-benzene(OXDs) were synthesized, and the chemical structures of the OXDs were confirmed by ¹H NMR, elemental analysis and FTIR. The optical, electrochemical and thermal properties of the OXDs were investigated by using UV-Vis, PL, CV and DSC. It is indicated that intramolecular exciplex can be formed between the 4-methoxyphenoxy and bis[2-(4-alkyoxyphenyl)-1,3,4-oxidiazol] and the end-alkoxy groups could restrain the formation of the intramolecular exciplex. The electrochemical properties of the OXDs show that OXDs were favorable for the electron injecting, transporting and hole blocking. DSC results prove that when the OXDs were substituted with shorter alkoxy groups(or without substituents), the crystal contents in OXDs were less in solid state and the stable non-crystalline morphology can be formed after heat-treating.

Key words: 1,3,4-Oxadiazoles, Intramolecular exciplex, Electron transport