Synthesis and Mesomorphic Properties of 4- Substituted Phenyl and Phenylthio-4′-[(S)-β- Ethoxypropoxy]-Benzoatest

Abstract

A variety of esters and thioesters of the type

were prepared by esterification of the acid with the phenols and thiols using the carbodiimide method. These compounds were of interest as possible ferroelectric liquid crystals. The required acid was prepared by basic hydrolysis of the ester obtained by alkylating methyl-4-hydroxybenzoate with the tosylate of (S)-2-(tetrahydro-2-pyranoxy)-1-propanol synthesized in two steps from (S)-ethyl lactate. Transition temperatures for these esters/thioesters were determined by hot-stage polarizing microscopy but no mesophases were observed in the esters and only a cholesteric phase in the Y = OC₁₂ thioester.

Key Words:

• liquid crystals
• ferroelectrics
• phenylthiobenzoates
• optically active
• NMR