The effects of alkylthio chains on the properties of symmetric liquid crystal dimers. [Dataset]

Abstract

In the design of organic molecules, sulfur can be interchanged with oxygen and during the 1960s and 1970s, in particular, saw use in liquid crystals. There has been a recent resurgence of interest in sulfur containing mesogens and the inclusion of sulfur has been achieved using, for example, terminal alkylthio chains, thiophene moieties,15–18 thiocyanate terminal groups, and thioester linking groups. The motivation for including sulfur in mesogenic materials is the increase in birefringence arising from the high polarisability of the sulfur atom. Highly birefringent mesogenic materials are of significant technological interest in areas such as fast third-order non-linear switching, liquid crystal displays, liquid crystal lenses, laser applications and colour tunable plasmonic devices. The synthetic route used to prepare the mS.OnO.Sm series is shown in Scheme 1 and for the mO.OnO.Om series in Scheme 2. A detailed description of the preparation of these series, including the structural characterisation data for all intermediates and final products, is provided in the ESI. The transitional properties for the mO.O6O.Om series are listed in Table 3. The transition temperatures for m = 2 were found to be in good agreement with those reported elsewhere.

Citation

CRUICKSHANK, E., STRACHAN, G.J., MAJEWSKA, M.M., POCIECHA, D., GORECKA, E., STOREY, J.M.D. and IMRIE, C.T. 2023. The effects of alkylthio chains on the properties of symmetric liquid crystal dimers. [Dataset]. New journal of chemistry [online], 47(15), pages 7356-7368. Available from: https://www.rsc.org/suppdata/d2/nj/d2nj06252f/d2nj06252f1.pdf

• Acceptance Date: Mar 17, 2023
• Online Publication Date: Mar 20, 2023
• Publication Date: Apr 21, 2023
• Deposit Date: Aug 8, 2023
• Publicly Available Date: Aug 8, 2023
• Publisher: Royal Society of Chemistry
• DOI: https://doi.org/10.1039/D2NJ06252F
• Keywords: Alkylthio chains; Symmetric liquid crystal dimers; Molecular modelling; X-ray diffraction
• Public URL: https://rgu-repository.worktribe.com/output/2035113
• Related Public URLs: https://rgu-repository.worktribe.com/output/2010311 (Journal article)
• Type of Data: PDF file.
• Collection Date: Dec 22, 2022
• Collection Method: All reagents and solvents that were available commercially were purchased from Sigma Aldrich, Fisher Scientific or Fluorochem and were used without further purification unless otherwise stated. Reactions were monitored using thin layer chromatography, and the appropriate solvent system, using aluminium-backed plates with a coating of Merck Kieselgel 60 F254 silica which were purchased from Merck KGaA. The spots on the plate were visualised by UV light (254 nm). For normal phase column chromatography, the separations were carried out using silica gel grade 60 Å, 40-63 µm particle size, purchased from Fluorochem and using an appropriate solvent system. All final products and intermediates that were synthesised were characterised using 1H NMR, 13C NMR and infrared spectroscopies. The NMR spectra were recorded on a 400 MHz Bruker Avance III HD NMR spectrometer. The infrared spectra were recorded on a Perkin Elmer Spectrum Two FTIR with an ATR; diamond cell. In order to determine the purity of the final products, elemental analysis or high-resolution mass spectrometry was used. C, H, N, S microanalysis were carried out by the Sheffield Analytical and Scientific Services Elemental Microanalysis Service at the University of Sheffield using an Elementar Vario MICRO Cube or by the Elemental Analysis Service at OEA Laboratories Limited using a CE Instruments EA1110 CHNS-O Elemental Analyser. The instruments were calibrated using series of different masses of sulphanilamide and acetanilide.