Synthesis of optically active 4,4,4-trifluoro-3-{4-(4-methoxyphenyl)phenyl}butanoic acid and its application to chiral dopant for nematic liquid crystals

Abstract

We synthesized an optically active 4,4,4-trifluoro-3-{4-(4-methoxyphenyl)phenyl}butanoic acid ( 5 *). New chiral dopants for nematic liquid crystals were derived from ( R)-(−)- 5 *, and their helical twisting power (HTP) values were measured. Their HTP values were largely influenced by the linkage between the asymmetric frame and the core moiety. The chiral dopant, ( R)-(+)-4,4,4-trifluoro-1-(4-hexyloxyphenyl)-3-{4-(4-methoxyphenyl)phenyl}-1-butanone (( R)-(+)- 7 *) showed the largest HTP value (−21.7 μm −1).