Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
Effects of Difluorophenyl Substituents on Structural, Redox, and Magnetic Properties of Blatter Radicals. / Gulyaev, Dmitry; Serykh, Andrey; Tretyakov, Evgeny и др.
в: Catalysts, Том 13, № 8, 1206, 08.2023.Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
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TY - JOUR
T1 - Effects of Difluorophenyl Substituents on Structural, Redox, and Magnetic Properties of Blatter Radicals
AU - Gulyaev, Dmitry
AU - Serykh, Andrey
AU - Tretyakov, Evgeny
AU - Akyeva, Anna
AU - Syroeshkin, Mikhail
AU - Gorbunov, Dmitry E.
AU - Maltseva, Svetlana V.
AU - Gritsan, Nina P.
AU - Romanenko, Galina
AU - Bogomyakov, Artem
N1 - D.G. (Dmitry Gorbunov), S.M. and N.G. acknowledge the core funding from the Russian Federal Ministry of Science and Higher Education (FWGF-2021-0002) and the Research Resource Center “Irkutsk Supercomputer Center SB RAS” for the computational resources. The authors wish to thank A. Korlyukov (INEOS RAS) for single crystal analyses of 3a at 100 K. Публикация для корректировки.
PY - 2023/8
Y1 - 2023/8
N2 - Blatter radicals 1-(3,4-difluorophenyl)-(1a) and 1-(2,4-difluorophenyl)-3-phenyl-1,4-dihydrobenzo[e][1,2,4]triazin-4-yl (1b) were prepared in good yields through oxidation of the corresponding amidrazones using MnO2 in dry CH2Cl2. Cyclic voltammetry showed that both radicals are oxidized and reduced chemically and electrochemically reversibly in accordance with −1/0 and 0/+1 processes. EPR spectroscopy indicated that spin density is mainly delocalized on the triazinyl moiety of the heterocycle. The structure of all paramagnets was unambiguously confirmed by single-crystal X-ray diffraction, and two different 1D chains of alternating radicals were identified. 3,4-difluorophenyl-derivatives 1a are packed into columns composed of two kinds of alternating centrosymmetric dimers, having comparatively short intermolecular distances. In crystals of 2,4-difluorophenyl-derivative 1b, the parallel arrangement of bicyclic moieties and phenyl rings favors the formation of 1D regular chains wherein the radicals are related by translation parallel to the crystallographic stacking axis. Magnetic susceptibility measurements in the 2–300 K region showed that in crystals of the radicals, strong antiferromagnetic interactions are dominant. Subsequent fitting of the dependence of χT on T with 12-membered looped stacks gave the following best-fit parameters: for 1a, g = 2.01 ± 0.05, J1/kB = −292 ± 10 K (according to BS-DFT calculations J2 = 0.12 × J1 and J3 = 0.61 × J1); for 1b, g = 2.04 ± 0.01 J1/kB = −222 ± 17 K. For comparison, in a nonfluorinated related radical, there are only very weak intermolecular interactions along the columns (J/kB = −2.2 ± 0.2 K). These results illustrate the magnitude of the influence of the difluorophenyl substituents introduced into Blatter radicals on their structure and magnetic properties.
AB - Blatter radicals 1-(3,4-difluorophenyl)-(1a) and 1-(2,4-difluorophenyl)-3-phenyl-1,4-dihydrobenzo[e][1,2,4]triazin-4-yl (1b) were prepared in good yields through oxidation of the corresponding amidrazones using MnO2 in dry CH2Cl2. Cyclic voltammetry showed that both radicals are oxidized and reduced chemically and electrochemically reversibly in accordance with −1/0 and 0/+1 processes. EPR spectroscopy indicated that spin density is mainly delocalized on the triazinyl moiety of the heterocycle. The structure of all paramagnets was unambiguously confirmed by single-crystal X-ray diffraction, and two different 1D chains of alternating radicals were identified. 3,4-difluorophenyl-derivatives 1a are packed into columns composed of two kinds of alternating centrosymmetric dimers, having comparatively short intermolecular distances. In crystals of 2,4-difluorophenyl-derivative 1b, the parallel arrangement of bicyclic moieties and phenyl rings favors the formation of 1D regular chains wherein the radicals are related by translation parallel to the crystallographic stacking axis. Magnetic susceptibility measurements in the 2–300 K region showed that in crystals of the radicals, strong antiferromagnetic interactions are dominant. Subsequent fitting of the dependence of χT on T with 12-membered looped stacks gave the following best-fit parameters: for 1a, g = 2.01 ± 0.05, J1/kB = −292 ± 10 K (according to BS-DFT calculations J2 = 0.12 × J1 and J3 = 0.61 × J1); for 1b, g = 2.04 ± 0.01 J1/kB = −222 ± 17 K. For comparison, in a nonfluorinated related radical, there are only very weak intermolecular interactions along the columns (J/kB = −2.2 ± 0.2 K). These results illustrate the magnitude of the influence of the difluorophenyl substituents introduced into Blatter radicals on their structure and magnetic properties.
KW - Blatter radicals
KW - antiferromagnetically coupled chains
KW - electrochemically reversible processes
KW - fluorinated organic compounds
KW - magneto-structural correlations
UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85169076747&origin=inward&txGid=1598f9b80fd3ccc8144aa0cc4cd165cf
UR - https://www.mendeley.com/catalogue/090f432c-f670-31fc-b9a0-52dd8c73f3ca/
U2 - 10.3390/catal13081206
DO - 10.3390/catal13081206
M3 - Article
VL - 13
JO - Catalysts
JF - Catalysts
SN - 2073-4344
IS - 8
M1 - 1206
ER -
ID: 59279373