Synthesis and Characterization of Cholesterol-Based Tetramers

Abstract

Novel symmetrical liquid-crystal tetramers were designed and synthesized. The length of the central spacer and the outer spacers has been varied. The molecular structures of the target compounds were confirmed by Fourier transform infrared and proton nuclear magnetic resonance spectroscopy. The thermal phase behavior of the tetramers was investigated by polarizing optical microscopy and differential scanning calorimetry. All of the liquid-crystal tetramers showed either a chiral nematic mesophase or chiral nematic and smectic mesophases.

Keywords:

• Chiral nematic phase
• cholesterol-based tetramer
• DSC
• POM
• smectic phase

Acknowledgment

Two of us (S.P. & S.C.) thank the Department of Science and Technology (New Delhi) for financial assistance. We are grateful to the Council of Scientific & Industrial Research (CSIR) (New Delhi) for their fellowships. We are also thankful to Dr. Raghunathan of Raman Research Institute, Bangalore, for providing the HRXRD data.