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A new synthetic approach for fluorinated alkoxytriphenylene discotic liquid crystals is presented. This methodology exploits the previously described photocyclodehydrofluorination (PCDHF) reaction for the preparation of fluorinated triphenylene derivatives coupled with a variety of nucleophilic aromatic substitution (S N Ar) reactions. This particular combination of reactions provides a versatile route to discotic materials with carefully controlled core fluorine and alkoxy tail content. In the course of these studies, new discotic materials with minimal tail content have been revealed. The mesogenic properties of these materials are reported, and their charge transport properties are measured using the time of flight technique.
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Investigation of the mesogenic behavior of alkoxy and fluorine tail terminated alkoxy nitrobiphenyls for chemoresponsive liquid crystals
Liquid crystal properties of compounds with a variety of polar terminal groups including cyano, fluoro, isothiocyanato, etc., were studied well, however, not enough attention was given to nitro terminal compounds. In this work, a series of fluorine tail terminated alkoxy nitrobiphenyl compounds were synthesised and their mesogenic properties were analysed. In addition, the simple alkoxy nitrobiphenyl compounds were synthesised and analysed in order to compare them with fluoro-alkoxy nitrobiphenyl compounds and for binary mixture analysis. Fluorine tail termination to the alkoxy chain does suppress the smectic phase that was observed for the simple alkoxy nitrobiphenyl compounds with longer chains. Fluorine tail terminated alkoxy nitrobiphenyl compounds with longer chains (C7-C10) show monotropic nematic phase around ambient temperature and supercooling properties and these compounds are useful for a binary mixture analysis. Moreover, computation and experimental analyses of the alkoxy nitrobiphenyl compounds were performed to investigate the potential use of these nitro terminal compounds as chemoresponsive liquid crystal materials.
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- PAR ID:
- 10358720
- Date Published:
- Journal Name:
- Liquid Crystals
- ISSN:
- 0267-8292
- Page Range / eLocation ID:
- 1 to 13
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1080/02678292.2022.2103193
