Synthesis and properties of novel columnar liquid crystals based on symmetrical and non-symmetrical 1,3,5-trisubstituted benzene derivatives

Abstract

In this structure–property correlation study we have investigated a number of novel disc-shaped compounds incorporating a 1,3,5-trisubstituted benzene at the central core. All the materials with peripheral arms attached through an ester linkage exhibited a columnar phase (Col_r or Col_h). The sole use of core–OOC–arm ester linkages resulted in a Col_r phase, whereas any inclusion of a core–COO–arm linkage caused a Col_h phase. We suggest that columnar mesophases are being generated due to space being occupied in the peripheral regions by the gradual offset stacking of individual molecules in the self-organised phase structure.

Keywords:

• synthesis
• columnar
• liquid crystals
• discotic

Acknowledgements

The authors wish to thank the EPSRC for the funding of PJS, and the Department of Chemistry, University of Hull, for their financial support of AW. They are also grateful to Mrs Julie Haley for her valuable contribution to this study.