New chiral side chains for ferro- and antiferro-electric liquid crystals derived from the preen-gland wax of the domestic goose

Abstract

(2R,4R,6R,8R)-2,4,6,8-Tetramethyldecanoic acid and (2R,4R,6R,8R)-2,4,6,8-tetramethyldecanol, as well as the (2R,4R,6R,8R) and the (2S,4R,6R,8R) diastereomers of 4,6,8-trimethyldecan-2-ol, have been obtained from the preen-gland wax of the domestic goose. Starting from these alkanols and alkanoic acid, novel ferro- and antiferro-electric liquid crystals bearing four methyl branchings in the chiral side chain have been synthesized and their mesomorphic and electro-optical properties have been investigated. The results obtained are compared with the properties of the respective chiral (S)-2-methyldecanoic acid, (S)-decan-2-ol and (S)-2-methyldecanol derivatives. The compounds with four methyl branchings in the chiral side chain are found to exhibit lower melting points, broader SmC* phase ranges, higher values of spontaneous polarization and larger tilt angles in comparison to the respective compound with only one methyl branching.