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Title: Asymmetric flavone-based liquid crystals: synthesis and properties

Abstract

A series of flavones (n-F) substituted at the 4', and 6 positions was prepared, characterised by NMR (1H,13C), HRMS, and studied for liquid crystal properties. The 4'-alkoxy,6-methoxyflavones (4-F–16-F) exhibit varying ranges of nematic and smectic A phases as evidenced by polarised optical microscopy and differential scanning calorimetry (DSC). As the tail length is increased, the smectic phase becomes more prevalent. Smectic phases for (8-F–16-F) were further analysed by powder X-ray diffraction (XRD), and the rate of structural transformations was explored by combined DSC/XRD studies. Flavonol 6-F–OH was also prepared but no mesogenic behaviour was observed. The molecular structures of 6-F and 6-F–OH were determined by single-crystal XRD and help to explain the differences in material properties. Additionally, fluorescence and electrochemical studies were conducted on solutions of n-F.

Authors:
 [1];  [1];  [1];  [2];  [3];  [1];  [4]
  1. Department of Chemistry, Virginia Military Institute, Lexington, VA, USA
  2. New Jersey Center for Biomaterials, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
  3. Department of Applied Mathematics, Virginia Military Institute, Lexington, VA, USA
  4. Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
USDOE
OSTI Identifier:
1375356
Resource Type:
Journal Article
Resource Relation:
Journal Name: Liquid Crystals; Journal Volume: 44; Journal Issue: 9
Country of Publication:
United States
Language:
ENGLISH
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Timmons, Daren J., Jordan, Abraham J., Kirchon, Angelo A., Murthy, N. Sanjeeva, Siemers, Troy J., Harrison, Daniel P., and Slebodnick, Carla. Asymmetric flavone-based liquid crystals: synthesis and properties. United States: N. p., 2017. Web. doi:10.1080/02678292.2017.1281450.
Timmons, Daren J., Jordan, Abraham J., Kirchon, Angelo A., Murthy, N. Sanjeeva, Siemers, Troy J., Harrison, Daniel P., & Slebodnick, Carla. Asymmetric flavone-based liquid crystals: synthesis and properties. United States. doi:10.1080/02678292.2017.1281450.
Timmons, Daren J., Jordan, Abraham J., Kirchon, Angelo A., Murthy, N. Sanjeeva, Siemers, Troy J., Harrison, Daniel P., and Slebodnick, Carla. Wed . "Asymmetric flavone-based liquid crystals: synthesis and properties". United States. doi:10.1080/02678292.2017.1281450.
@article{osti_1375356,
title = {Asymmetric flavone-based liquid crystals: synthesis and properties},
author = {Timmons, Daren J. and Jordan, Abraham J. and Kirchon, Angelo A. and Murthy, N. Sanjeeva and Siemers, Troy J. and Harrison, Daniel P. and Slebodnick, Carla},
abstractNote = {A series of flavones (n-F) substituted at the 4', and 6 positions was prepared, characterised by NMR (1H,13C), HRMS, and studied for liquid crystal properties. The 4'-alkoxy,6-methoxyflavones (4-F–16-F) exhibit varying ranges of nematic and smectic A phases as evidenced by polarised optical microscopy and differential scanning calorimetry (DSC). As the tail length is increased, the smectic phase becomes more prevalent. Smectic phases for (8-F–16-F) were further analysed by powder X-ray diffraction (XRD), and the rate of structural transformations was explored by combined DSC/XRD studies. Flavonol 6-F–OH was also prepared but no mesogenic behaviour was observed. The molecular structures of 6-F and 6-F–OH were determined by single-crystal XRD and help to explain the differences in material properties. Additionally, fluorescence and electrochemical studies were conducted on solutions of n-F.},
doi = {10.1080/02678292.2017.1281450},
journal = {Liquid Crystals},
number = 9,
volume = 44,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2017},
month = {Wed Feb 01 00:00:00 EST 2017}
}
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