Synthesis and properties of hydroxy tail-terminated cyanobiphenyl liquid crystals

ABSTRACT

Two series of new hydroxy tail-terminated cyanobiphenyl compounds are described. The 4′-ω-hydroxyalkynyl-4-cyanobiphenyl compounds (1a–1g) were synthesised as the key intermediates to the 4′-?ω-hydroxyalkyl-4-cyanobiphenyl compounds (2a–2g) obtained upon reduction of the acetylenes. Many of these ω-hydroxyalkynyl and ω-hydroxyalkyl cyanobiphenyl compounds exhibit nematic mesophases and they also serve as precursors for the synthesis of other interesting materials. Using density functional theory, we calculate the dipole moment of all relevant ω-hydroxyalkynyl and ω-hydroxyalkyl cyanobiphenyl compounds and find a correlation between the calculated dipole moments and measured crystalline to nematic or isotropic liquid transition temperatures.

GRAPHICAL ABSTRACT

KEYWORDS:

• Hydroxy terminated
• cyanobiphenyl
• nematic phases
• dipole moment

Acknowledgements

Research was supported by the NSF. Award Number: 1435195 Project Title: Chemoresponsive Liquid Crystals Based on Metal Ion-Ligand Coordination.

T. S. and M.M.’s computational work was performed at supercomputing centres located at the Environmental Molecular Sciences Laboratory (EMSL), which is sponsored by the Department of Energy (DOE) Office of Biological and Environmental Research at Pacific Northwest National Laboratory (PNNL); the Center for Nanoscale Materials (CNM) at Argonne National Laboratory (ANL), supported by DOE Contract DE-AC02-06CH11357; and the National Energy Research Scientific Computing Center (NERSC), supported by DOE Contract DE-AC02-05CH11231.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary material

Supplemental data can be accessed here.

Additional information

Funding

This work was supported by the National Science Foundation: [1435195].