Mesomorphic and ferroelectric properties of novel optically active compounds derived from (R)-3-hydroxynonanoic acid

Abstract

Novel optically active compounds derived from (R)-3-hydroxynonanoic acid as shown in a general formula (I)

have been synthesized and their mesomorphic and ferroelectric properties have been investigated. The kind of mesophases and the transition temperatures depend strongly on the linkage groups and the substituents in the core. The compounds with an unsubstituted core show non-titled smectic mesophases (smectic A or B). The chiral smectic C phase appears in the compounds having a central ester linkage and a chloro-substituent as the A ₁ or B ₁ position and in the compound having a central -OCH₂- linkage and a chloro-substituent at the A ₁ position. The maximum spontaneous polarization (500 μC/m²) was observed in 4-dodecyloxy-3-chlorobenzoyl-oxyphenyl (R)-3-hydroxynonanoate. The thermal stability of each mesophase and the ferroelectric properties have been discussed from the structural point of view.