Synthesis and helical twisting power of chiral dopants derived from optically active 4,4,4-trifluoro-3-(6-methoxy-2-naphthyl)butanoic acid for nematic liquid crystals

Abstract

We synthesized an optically active carboxylic acid, 4,4,4-trifluoro-3-(6-methoxy-2-naphthyl)butanoic acid (TFMNBA)[1]. New chiral dopants having two chiral centers were derived from 1*, and their helical twisting power (HTP) values were evaluated. The chiral parts and the core part were linked with ester bonds or ether bonds, and the ether type chiral dopants showed larger HTP values than the ester type chiral dopants. The chiral dopant, an optically active 4,4'-bis(4,4,4-trifluoro-3-(6-methoxy-2-naphthyl)butyloxy)biphenyl,showed the largest HTP value (32.1 um-1) in the series .