Preparation and thermal properties of new liquid crystals with a 2-benzoyloxy-2,4,6-cycloheptatrien-1-one core

Abstract

New liquid crystals with 2-benzoyloxy-2,4,6-cycloheptatrien-1-one (2-benzoyloxytropone) core were prepared. The [1,9] sigmatropic dynamic property in a 5-alkoxy-2-(4-alkoxybenzoyloxy)tropone structure was shown to play a decisive role in revealing mesophases by comparison with 5-alkoxy-2-(4-alkoxybenzyloxy)tropones and 7-bromo-5-dodecyloxy-2-(4-dodecyloxybenzoyloxy)tropone, which had no such molecular dynamic property. These liquid crystals showed varios phases, depending on the length of the alkyl chains.