Monosubstituted ferrocene liquid crystals containing click triazole with a wide nematic phase temperature range

ABSTRACT

New monosubstituted ferrocenomesogens of the 1,4-substituted-1,2,3-triazole series 3a-3d and the 5-halogen-1,4-substituted-1,2,3-triazole series 4a-4d were successfully synthesised through a facile and versatile synthetic route using click reactions with moderate yields, in different atmospheres, and catalysed by different amounts of CuX (X = Br, I). Two series of compounds exhibited a typical nematic liquid crystal texture, and the 5-halogen-1,4-substituted-1,2,3-triazole series 4 had a wider mesomorphic temperature range than the corresponding series 3 due to the effect of the halogen atom substituent on the triazole. These compounds showed similar absorption spectra, but the fluorescence emission spectra of 4 were obviously redshift relative to 3. Cyclic voltammetry investigations revealed that the redox-active ferrocenyl groups of 3 and 4 follow one-electron transfer processes.

GRAPHICAL ABSTRACT

KEYWORDS:

• Liquid crystals
• ferrocenomesogens
• nematic phase
• click chemistry
• triazoles
• halogen atom substituent effect

Acknowledgements

This work was supported by the National Natural Science Foundation of China [number 51073112, 51273133], the Key Foundation of Sichuan Normal University [number 15ZD006] and also the Special Funds for Sharing Large Precision Equipment of Sichuan Normal University [numbers DJ2016-22, DJ2015-32].

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary-Material

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Additional information

Funding

This work was supported by the National Natural Science Foundation of China [number 51073112, 51273133], the Key Foundation of Sichuan Normal University [number 15ZD006] and also the Special Funds for Sharing Large Precision Equipment of Sichuan Normal University [numbers DJ2016-22, DJ2015-32].