Synthesis and Phase Behavior of Ferroelectric Chiral Imines from (S)-(-)-Ethyllactate

We have synthesized new series of the Ferroelectric Chiral Imines: (R)-(-)-4′-[2-methylhexyl-(4-n-alkoxybenzilidene)], (R)-(-)-4′-[2-methylhexyl-(4-n-alkoxybenzoyloxy)benzilidene] and (R)-(-)-4′-[2-methylhexyl-(4-n-alkoxycinnamoyloxy)benzilidene]anilines, or series 1, 2 and 3, respectively, derived from (S)-(-)-ethyllactate. Series 1 did not show liquid crystal phase behavior and series 2 and 3 show chiral smectic C and smectic A phase over a wide range of temperatures, and a cholesteric phase as well. The phase transition behavior is described and for the series 1, AM1 semiempirical calculations are presented.