Synthesis, Crystal Structure, and Mesomorphic Properties of Liquid Crystals with a Bis(tropon-2-yl)-4,4’-azobisbenzoate Core

Abstract

New troponoid liquid crystals with bis(tropon-2-yl)-4,4’-azobisbenzoate core were prepared. Compound (1) had enantiotropic nematic and/or smectic C phase. The crystals of 1a had intermolecular π-π interactions between azobenzene planes and between tropone rings. The nematic liquid crystal (1a) did not form any layer structure in crystal state. X-ray diffraction studies revealed that 1c and 1d formed the tilted layers in the smectic C phase.