A New Mesomorphism of the Alky 4-(2-Perfluoroalkyl)ethoxybenzoate Derivatives
The liquid-crystalline properties of the homologous members of alkyl 4-(2-perfluorooctyl)ethoxy-3-R-benzoates (R = H (<b>1</b>), NO<sub>2</sub> (<b>3</b>), Br (<b>4</b>)) show a new mesomorphic behavior. The lower alkyl (methyl–pentyl) esters of <b>1</b> exhibit a smectic A phase, and the smectic A-isotropic transition temperature tends to decrease with increasing the carbon number of the alkyl group, where the layer spacing of the smectic A phase tends to become short with increasing carbon chain length. The hexyl–decyl esters are non-mesogenic, and the after members again show a smectic A phase. The similar trend has been found for <b>3</b> and <b>4</b>. Homologous members of alkyl 4-(2-perfluorodecyl)ethoxybenzoates (<b>2</b>) also show a similar thermal behavior. The smectic properties are strongly dependent on the relative constitution of the perfluoroalkyl group to the alkyl one within the molecule. The molecular arrangement of the smectic A phase is discussed.
- Bulletin of the Chemical Society of Japan
Bulletin of the Chemical Society of Japan 71(11), 2735-2739, 1998-11-15
The Chemical Society of Japan