Synthesis, single crystal structure and liquid crystalline properties of bent-shaped 2,5-diaryl 1,3,4-oxadiazoles

Abstract

Two bent-shaped 1,3,4-oxadiazole-based compounds, namely 2-[4-(2-(4-methylphenyl)-(E)-1-ethenyl)]phenyl-5-(4-pentyloxyphenyl)-1,3,4-oxadiazole 5a and 2-[4-(2-(4-fluorophenyl)-(E)- ethenyl-5-(4-pentyloxyphenyl)-1,3,4-oxadiazole 5b, were synthesised and their liquid crystalline properties were studied in this paper. Compound 5a exhibited an enantiotropic nematic mesophase, while 5b displayed an enantiotropic smectic A phase. No banana-shaped mesophases were found in these mesogens, although they adopt a bent-shaped molecular structure as confirmed by the single X-ray diffraction crystallography.

Keywords:

• heterocyclic liquid crystals
• stilbene
• single X-ray crystallography
• synthesis

Acknowledgement

We are grateful for financial support from the National Natural Science Foundation of China (No. 20772064).