Two origins for twisting power of a binaphthyl derivative in a host nematic liquid crystal

Abstract

We prepare a series of homologues of novel binaphthyl derivatives, (R)‐2, 2′‐bis{ω‐[4‐(4‐(octyloxycarbonyl)phenyl)phenyloxycabonyl]alkyloxy}‐1, 1′‐binaphthyl [(R)‐Bi‐n], and investigate their induced helical senses and pitches in different host nematic liquid‐crystalline compounds. Pronounced odd–even effects were observed for the induced helical structure in each mixture with 5‐heptyl‐2‐(4‐hexyloxyphenyl)pyrimidine. Temperature‐dependent helical twist inversion was observed for the mixture doped with the odd members, whereas a right‐handed helix was observed for the mixture doped with the even members. On the other hand, a left‐handed helix was induced in each mixture with 4‐methyloxyphenyl 4‐pentylcyclohexane. We discuss the change in sign of the induced pitch in terms of chirality transfer from the binaphthyl derivative to a host nematic liquid crystal.

Acknowledgements

This work was partially supported by a Grant for Priority Research Designated by the President of Hirosaki University and a Grant‐in‐Aid for Scientific Research from the Japan society for the promotion of science (No. 19550175).