Some New Mesogenic Esters Incorporating the 1,4-Disubstituted Bicyclo(2.2.2)octane Ring System

Abstract

Abstract A variety of one-ring, two-ring, and three-ring esters incorporating one or two 1.4-disubstituted bicyclo(2.2.2)octane rings has been synthesised. In some cases the esters are fully alicyclic, e.g., terminally alkyl substituted alkyl bicyclo-octanoates, bicyclo-octyl bicyclo-octanoates and bicyclo-octyl cyclohexanoates. In others, the acidic moiety consists of one or two benzene rings or a benzene ring linked to a cyclohexane ring. The range of esters also includes some alkyl and bicyclo-octyl esters in which the acidic moiety contains a bicyclo-octane linked to a benzene ring system. The transition temperatures for the different types of ester are reported and compared with one another and with literature values for related esters. Results obtained from measurements of viscosity, birefringence, and electro-optical characteristics on some of the fully alicyclic esters are also reported.