排序方式: 共有112条查询结果,搜索用时 15 毫秒
1.
Romanenko G. V. Fokin S. V. Bogomyakov A. S. Zueva E. M. Ovcharenko V. I. 《Journal of Structural Chemistry》2022,63(3):441-450
Journal of Structural Chemistry - The structures of Ni(II), Cu(II), and Zn(II) complexes with anions of 2,5-pyrrolyl-disubstituted nitronyl nitroxide (L1) and iminonitroxide (L2) diradicals (HL1 is... 相似文献
2.
Romanenko G. V. Letyagin G. A. Maryunina K. Yu. Bogomyakov A. S. Nishihara S. Inoue K. Ovcharenko V. I. 《Russian Chemical Bulletin》2020,69(8):1530-1536
Russian Chemical Bulletin - The study is concerned with structural rearrangements in the crystals of heterospin complexes Cu(hfac)2 with nitroxide radicals LR (hfac is hexafluoroacetylacetonate, LR... 相似文献
3.
E. V. Tretyakov A. S. Bogomyakov E. Yu. Fursova G. V. Romanenko V. N. Ikorskii V. I. Ovcharenkoa 《Russian Chemical Bulletin》2006,55(3):457-463
The molecular and crystal structures of porphyrexides, viz., 4-amino-2-imino-(1) and (Z)-2-amino-4-bromoimino-5,5-dimethyl-4,5-dihydro-1H-imidazole 1-oxyls (7), and their diamagnetic precursors were determined. Compound 1 is kinetically unstable because it is oxidized with atmospheric oxygen to form (E)-1,2-bis[1-amino-1-(cyanoimino)-2-methyl-propan-2-yl]diazene 1,2-dioxide.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 441–447, March, 2006. 相似文献
4.
S. V. Fokin G. A. Letyagin G. V. Romanenko A. S. Bogomyakov M. V. Petrova V. A. Morozov V. I. Ovcharenko 《Russian Chemical Bulletin》2018,67(1):61-70
Alkali metals form mutinuclear compounds with redox-active singly and doubly reduced derivatives of sterically of hindered о-benzoquinones. Complexes [Na6(Cat)3(THF)7]?4THF, [Na5(Cat)2(SQ)(THF)5], [Na4(SQ)4(THF)4]?THF?C6H14, [Na4(3,5-SQ)4(THF)4], [K4(SQ)4(THF)4]?4THF and [Li3(SQ)3(THF)3]?THF (Cat is catecholate, SQ is semiquinonate) possessing high sensitivity to atmospheric oxygen were synthesized and their structures were determined. Magnetochemical measurements and quantum chemical calculations revealed that variation of the alkali metal and/or change in the structure of the polymetallic core significantly affect the energy of exchange interaction between the unpaired electrons of the paramagnetic ligands framing the polynuclear metal core formed by s-elements. 相似文献
5.
E. V. Tret’yakov V. G. Vasil’ev A. S. Bogomyakov G. V. Romanenko M. V. Fedin I. S. Antipin S. E. Solov’eva A. I. Konovalov R. Z. Sagdeev V. I. Ovcharenko 《Russian Chemical Bulletin》2013,62(2):543-547
A reaction of calix[4]arene tetraaldehyde with 2,3-bis(hydroxyamino)-2,3-dimethylbutane in DMF resulted in the corresponding 1,3-dihydroxyimidazolidine tetraadduct, whose oxidation gave a calix[4]arene (1,3-alternate) bearing four nitronyl nitroxyl-containing substituents at the upper rim. 相似文献
6.
S. V. Fokin E. T. Kostina E. V. Tret’yakov G. V. Romanenko A. S. Bogomyakov R. Z. Sagdeev V. I. Ovcharenko 《Russian Chemical Bulletin》2013,62(3):661-671
The synthesis, structure, and magnetic properties of the products of the reaction for Cu(hfac)2 (hfac is hexafluoroacetylacetonate) with spin-labeled nitronyl nitroxides 4,4,5,5-tetramethyl-2-(1-R-1H-pyrazol-5-yl)-3-imidazoline-1-oxyl 3-oxides L5/R (R = Me, Et, Pr, Bu), viz., binuclear complex [Cu(hfac)2L5/Me]2 and chain polymer complexes [Cu(hfac)2L5/R]n, are described. The polymer heterospin chains are built according to “head-to-head” (R = Me, Et, Pr, Bu) and “head-to-tail” (R = Pr, Bu) motifs. Compound [Cu(hfac)2L5/Me]2 is characterized by the ability to reveal the reversible effect of thermally induced spin transition at a temperature about 75 K (without hysteresis). In the set of heterospin CuII compounds with spin-labeled pyrazoles, this is the earlier unknown example of a molecular complex exhibiting a similar magnetic anomaly. 相似文献
7.
Prof. Dr. Evgeny V. Tretyakov Dr. Svetlana I. Zhivetyeva Dr. Pavel V. Petunin Dmitry E. Gorbunov Prof. Dr. Nina P. Gritsan Prof. Dr. Irina Yu. Bagryanskaya Dr. Artem S. Bogomyakov Dr. Pavel S. Postnikov Dr. Maxim S. Kazantsev Prof. Dr. Marina E. Trusova Dr. Inna K. Shundrina Dr. Elena V. Zaytseva Dr. Dmitriy A. Parkhomenko Prof. Dr. Elena G. Bagryanskaya Prof. Dr. Victor I. Ovcharenko 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(46):20885-20891
Thermally stable organic diradicals with a triplet ground state along with large singlet-triplet energy gap have significant potential for advanced technological applications. A series of phenylene-bridged diradicals with oxoverdazyl and nitronyl nitroxide units were synthesized via a palladium-catalyzed cross-coupling reaction of iodoverdazyls with a nitronyl nitroxide-2-ide gold(I) complex with high yields. The diradicals exhibit high stability and do not decompose in an inert atmosphere up to 180 °C. For the diradicals, both substantial AF (ΔEST≈−64 cm−1) and FM (ΔEST≥25 and 100 cm−1) intramolecular exchange interactions were observed. The sign of the exchange interaction is determined both by the bridging moiety (para- or meta-phenylene) and by the type of oxoverdazyl block (C-linked or N-linked). Upon crystallization, diradicals with the triplet ground state form unique one-dimensional exchange-coupled chains with strong intra- and weak inter-diradical ferromagnetic coupling. 相似文献
8.
O.?G.?Shakirova L.?G.?LavrenovaEmail author N.?V.?Kuratieva A.?S.?Bogomyakov L.?A.?Sheludyakova A.?P.?Mosalkova Yu.?V.?Grigoriev 《Journal of Structural Chemistry》2017,58(5):919-925
Iron(II) dicyanamide and isothiocyanate compounds with 2-(2-tert-butyltetrazol-5-yl)pyridine (L) of the composition [FeL2(C2N3)2]?2H2O (I) and [FeL2(NCS)2]H2O (II) are synthesized and studied. The compounds are examined using powder and single crystal XRD (for I), electron (diffuse reflectance spectra) and IR spectroscopy, static magnetic susceptibility. The analysis of the dependence μeff(Т) indicates that the exchange interactions of antiferromagnetic nature appear between the iron(II) ions at temperatures below 50 K. 相似文献
9.
E. Yu. Fursova O. V. Kuznetsova G. V. Romanenko A. S. Bogomyakov V. I. Ovcharenko 《Russian Chemical Bulletin》2010,59(2):337-341
The heterospin mixed-ligand complex [Ni6(OH)4Piv4(hfac)4(NIT-Ph)2] (1) (NIT-Ph is 4,4,5,5-tetramethyl-2-phenyl-4,5-dihydro-1H-imidazol-1-oxyl 3-oxide, hfac is hexafluoroacetylacetonate, and Piv is pivalate) was synthesized. The method for the synthesis
of complex 1 is based on the replacement of acetone molecules in the hexanuclear complex containing the hexafluoroacetylacetonate and
pivalate ligands [Ni6(OH)4Piv4(hfac)4(Me2CO)4] by NIT-Ph molecules. Two monodentate NIT-Ph molecules replace four acetone molecules, because the coordination of the O
atom of the nitroxide group results in the blocking of one of the positions in the coordination environment of NiII the access to which is hindered by the phenyl ring of NIT-Ph. As a result, these ions are in a square-pyramidal environment
unusual of NiII. In the low-temperature range, the dependence of the magnetization of 1 on the magnetic field is described by the Brillouin function. The reaction of [Ni6Piv4(hfac)4(OH)4(Me2CO)4] with the nitronyl nitroxide radicals 4,4,5,5-tetramethyl-2-(4-pyridyl)-4,5-dihydro-1H-imidazol-1-oxyl 3-oxide (NIT-p-Py) or 4,4,5,5-tetramethyl-2-(1-methyl-1H-imidazol-5-yl)-4,5-dihydro-1H-imidazol-1-oxyl 3-oxide (NIT-Iz) containing the pyridine or 1-methylimidazol-5-yl substituent, respectively, in the side
chain is accompanied by the decomposition of the polynuclear fragment and affords the mononuclear complexes Ni(hfac)2(NIT-p-Py)2 and Ni(hfac)2(NIT-Iz)2, respectively. The reaction of 4,4,5,5-tetramethyl-2-(1-methyl-1H-imidazol-5-yl)-4,5-dihyd-ro-1H-imidazol-1-oxyl (Im-Iz), which is the imine analog of NIT-Iz, with [Ni6Piv4(hfac)4(OH)4(Me2CO)4] afforded the decanuclear complex [Ni10(OH)8Piv4(hfac)8(Im-Iz)2(H2O)6]. The molecular and crystal structures of all heterospin compounds were determined, and the magnetic properties of all compounds
were investigated in the 2–300 K temperature range. 相似文献
10.
A. V. Arapova M. P. Bubnov N. N. Smirnova A. V. Markin I. A. Letyanina N. A. Skorodumova A. S. Bogomyakov G. A. Abakumov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2014,88(1):1-6
The heat capacity of di-(2-pyridyl)amine-bis-(4-methoxy-3,6-di-tert-butyl-o-benzosemiquinone)cobalt in the temperature range from 7 to 370 K was investigated by means of precise adiabatic vacuum calorimetry. It was established that the phase transition associated with the redox-isomeric transformation of the semiquinone-catecholate form of the complex into the bis-semiquinone form is observed above 260 K; this transition is not completed due to thermal destruction that begins at 367 K. The magnetic moment values in the temperature range from 5 to 350 K and the EPR spectra in the temperature range from 130 to 290 K, which confirm the nature of the phase transition, were obtained for the investigated complex. The standard thermodynamic functions C p pO (T), H○(T)-H○(0), S○(T), and G○(T)-H○(0), were calculated from the data on heat capacity in the temperature range from T → 0 to 260 K. Analysis of the low temperature heat capacity on the basis of Debye’s theory of the heat capacity of solids and the multifractional model testifies to the chain-layered structural topology of the investigated complex. 相似文献