New Chiral Liquid Crystal Compounds: (S)-(+)-4-[4-(Methyl)-1, 3-dioxolan-2-yl]-phenyl-4-n-alkoxybenzoates and 4-n-alkoxycinnamates

Abstract

New liquid crystal compounds, (S)-(+)-[4-(methyI)-1,3-dioxolan-2-yl]phenyl-4-n-alkoxybenzoates, I, and (S)-(+)-[4-(methyl)-1,3-dioxolan-2-yl]phenyl-4-n-alkoxycinnamates, II, have been synthesized and the thermotropic liquid-crystalline behaviour investigated. The compounds did not exhibit a chiral smectic C phase. The mesophases present in these compounds are cholesteric and smectic A phases. The transition temperatures of series II are higher than those for series I.

Key Words:

• Liquid crystals
• 1, 3-dioxolane ring
• smectic A
• cholesteric phase.