Synthesis and mesomorphic properties on the series of 2-(4-alkylphenyl)-6-methylquinolines and 2-(4-alkoxyphenyl)-6-methylquinolines

Abstract

Two homologous series of quinoline-containing liquid crystalline compounds were synthesised. Preparation of these compounds was completed in a short two-step reaction. Fair to good two-step overall yields of 63%–68% and 50%–60% were obtained respectively for the liquid crystalline compounds of 2-(4-alkylphenyl)-6-methylquinolines (nPQMe, n = 4–8) and 2-(4-alkoxyphenyl)-6-methylquinolines (mOPQMe, m = 3–7). Spectral analyses were in accordance with the expected structures. Polarising optical microscopy showed both series of compounds only display a nematic phase. Their thermotropic behaviours were further confirmed by differential scanning calorimetry.

Keywords:

• synthesis
• quinoline-containing compounds
• liquid crystals
• thermal analysis

Acknowledgement

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