Some Three-Ring Esters Containing aFive-Membered Heteroaromatic Ring. A Comparison of Liquid Crystal Properties

Abstract

Ninety compounds, over seventy of which are members of a number of homologous series of three-ring esters containing a 5-membered heteroaromatic ring, have been synthesized in order to establishhow a change in the position of the heterocyclic ring influences liquid crystal behavior when comparedwith corresponding all-benzenoid esters. The liquid crystal properties of these esters, which showconsiderable variation, are discussed. One group of compounds shows unusual phase behavior, involvingan unidentified (smectic?) phase and photomicrographs of optical textures of this phase are included.