Microwave-assisted synthesis of novel mixed tail rufigallol derivatives

Abstract

Microwave-assisted syntheses of five new series of rufigallol-based mesogens are reported with branched alkyl chains at the peripheral positions. The chemical structures of these newly synthesised compounds were determined by ¹H nuclear magnetic resonance (NMR), ¹³C NMR, infrared spectroscopy, ultraviolet spectroscopy and elemental analysis. The thermotropic liquid crystalline properties were investigated by polarising optical microscopy (POM), differential scanning calorimetry and X-ray diffractometry. Most of the derivatives were found to be liquid crystalline over a wide temperature range.

Keywords:

• rufigallol
• liquid crystals
• microwave-assisted synthesis
• branching

Acknowledgements

This work was carried out with the financial support from IISER Mohali and Department of Science and Technology, Key Project DST-12-0035 ‘Liquid Crystal Nanocrystal-A new resource of functional soft materials for nanosciences’. We are grateful to NMR research facility at IISER Mohali for recording NMR spectrum. S. Setia and S. Sidiq acknowledge the receipt of a graduate fellowship from CSIR-NET and UGC-NET, respectively.