Helical Twisting Power of Optically Active Spiro Compounds Having 3,3'-(4H,4'H)-Spiro(2H-naphtho[1,2-b]pirane) Skeleton

Abstract

The chiral dopants having a spiro structure were synthesized from optically active 3,3'-(4H,4'H)-spirobi(2H-naphtho[1,2-b]pyran)-6,6'-dicarboxylic acid for nematic liquid crystals, and their helical twisting power (HTP) values were determined. It was found that the novel ester-linked spiro chiral dopants showed large HTP values. On the other hand, the ether-linked chiral dopants showed relatively small HTP values.