Synthesis and mesomorphic behaviour of the series of 2-(4-alkoxyphenyl)-6-methoxyquinolines and 2-(4-alkoxybiphenyl-4′-yl)-6-methoxyquinolines

Abstract

Two homologous series of quinoline-containing liquid crystalline compounds were synthesised. Synthesis of these compounds was completed using a short two-step reaction. Fair to good overall two-step yields of 72–79% and 36–50% were obtained for the liquid crystalline compounds of 2-(4-alkoxyphenyl)-6-methoxyquinolines (mO-PQOMe, m = 3–8) and 2-(4-alkoxybiphenyl-4′-yl)-6-methoxyquinolines (nO-PPQOMe, n = 3–8), respectively. The spectral analysis results were in agreement with the expected structures. Polarised optical microscopy showed that both series of compounds exhibit only a nematic phase. The thermotropic behaviours of these compounds were further confirmed using differential scanning calorimetry.

Keywords:

• chemical synthesis
• quinoline-containing compounds
• liquid crystals
• thermotropic behaviour

Acknowledgements

Financial support of our work by the office of research and development of Fu Jen Catholic University is gratefully acknowledged.