Synthesis of a Terpene-Based New Chiral Inducer and Preparation of an Asymmetric Polymer

A new chiral compound was synthesized based on L-borneol. A cholesteric liquid crystal (LC) electrolyte solution was prepared by adding it as a chiral inducer to a nematic LC. A chiral poly(3,4-ethylenedioxythiophene) (PEDOT*, * = asymmetry) film was prepared by electrochemical polymerization in the induced cholesteric LC. The PEDOT* film showed a maximum absorption band due to a π–π* transition in the UV-Vis absorption and bisignate Cotton effect in the reduced state in circular dichroism (CD). The CD spectrum indicates that PEDOT* backbones form right-handed helical aggregation. However, the maximum optical absorption band due to π–π* transition of the PEDOT* decreases and a new absorption band appears at long wavelengths upon oxidation due to generation of polarons as charge carriers. Bisignate Cotton effect disappears and broadly negative CD signal appears at long wavelengths in the oxidized state.