Highly branched mesomorphic iron(III) complexes with a long alkyl fragments on periphery

• Published in: Journal of molecular liquids 2020-12, Vol.320, p.114505, Article 114505
• Main Authors: Gruzdev, M.S., Chervonova, U.V., Vorobeva, V.E., Kolker, A.M.
• Format: Article
• Language: English
• Subjects: Dendrimers; EPR; Liquid crystals; Schiff base
• ISSN: 0167-7322; 1873-3166
• DOI: 10.1016/j.molliq.2020.114505

The Fe(III) complexes of the new series of highly branched Schiff base dendrimers were synthesized by a one-step reaction without isolation the ligand from the solution. The coordination compounds obtained were characterized by mass, elemental and chromatographic analysis, infrared spectra and 1H NMR spectral measurement. The phase transitions were investigated by differential scanning calorimetry and the presence of the liquid crystalline properties was established by polarizing optical microscopy. The results showed that all the members in this series exhibit enantiotropic mesomorphic properties in the same temperature range 310–320 K. Two-dimensional nature of magnetism has found for complexes. Electron paramagnetic resonance spectra in the temperature range from 260 K to 340 K were recorded in the heating-cooling cycle to study liquid-crystalline properties. [Display omitted] •The Fe(III) complexes, [FeL2]X, of highly branched Schiff base dendrimers have been synthesized.•The structure of the obtained metal complexes was confirmed by different methods.•The phase transitions were investigated and the presence of the liquid crystalline properties was established.•Two-dimensional nature of magnetism has been found for complexes.