Abstract
The inclusion of secondary and tertiary benzanilide-based mesogenic groups into liquid crystal dimers is reported as a means to develop new materials. Furthermore, substitution at the nitrogen atom is shown to introduce an additional synthetic ‘handle’ to modify the molecular structure of the tertiary materials. The design of these materials has proved challenging due to the strong preferences of 3° benzanilides for the E amide conformation. In this work, lateral substitution is used to modify the conformational preferences of the amide linkage and promote liquid crystallinity for a series of N-methyl benzanilide dimers. As the proportion of the E conformer decreases, the nematic-isotropic transition temperatures increase, and enantiotropic nematic behaviour is observed. We also report the synthesis and characterisation of the analogous 2° benzanilide-based materials, which show nematic and twist-bend nematic behaviour. This approach highlights the effects that seemingly small structural modifications, such as the inclusion and position of a methyl group, can have on molecular shape and hence, liquid crystalline behaviour.
Original language | English |
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Article number | e202200758 |
Number of pages | 9 |
Journal | ChemPhysChem |
Volume | 24 |
Issue number | 7 |
Early online date | 30 Dec 2022 |
DOIs | |
Publication status | Published - 3 Apr 2023 |
Bibliographical note
Open access via the Wiley AgreementFunder: National Science Centre. Grant Number: 2021/43/B/ST5/00240
Acknowledgments
D.P. gratefully acknowledges financial support from the National Science Centre (Poland) under the grant no. 2021/43/B/ST5/00240.
Keywords
- Benzanilide
- conformational analysis
- liquid crystals
- nematic phase
- NMR spectroscopy