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Cover Picture: Coordination Chemistry of N‐Heterocyclic Nitrenium‐Based Ligands (Chem. Eur. J. 19/2015)
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3.
A recent conjecture of Myerson and Sander concerns divisibility properties of certain multinomial coefficients. We obtain results in this direction by further pursuing a line of attack developed earlier by the first author. 相似文献
4.
E. V. Sennikova A. S. Antsyshkina G. G. Sadikov A. V. Bicherov O. Yu. Korshunov G. S. Borodkin M. S. Korobov V. S. Sergienko N. N. Kharabaev A. D. Garnovskii 《Russian Journal of Coordination Chemistry》2008,34(5):315-321
The chelate and molecular complexes of 2-(2-benzazolyl, perimidyl)-indandiones-1,3 were synthesized for the first time. The structures of the ligands (tautomeric forms) and complex compounds were determined from the X-ray diffraction, 1H, 13C NMR, and IR data and the quantum-chemical calculations (RHF SCF in 6-31 G** basis). 相似文献
5.
Borodkin G. I. Popov S. A. Pokrovskii L. M. Shubin V. G. 《Russian Journal of Organic Chemistry》2003,39(5):747-749
Russian Journal of Organic Chemistry - 相似文献
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Arie L. Gutman Marina Etinger Gennady Nisnevich Felix Polyak 《Tetrahedron: Asymmetry》1998,9(24):1022
The enantiomerically pure chiral benzocyclic amines 6–8 were obtained by asymmetric transamination of the corresponding prochiral ketones 9a–c. The method involves: (a) formation of chiral imines 10a–c from the prochiral ketones 9a–c and the inexpensive chiral auxiliary (R)- or (S)-phenylethylamine (PEA); (b) asymmetrically induced reduction of these imines to the diastereomeric amines 11a–c and 12a–c; (c) catalytic hydrogenation to remove the benzylic fragment of the chiral PEA auxiliary. The stereoselectivity of the imine reduction, as well as the regioselectivity of the catalytic hydrogenation, are strongly dependent on the size of the saturated ring condensed with the benzene ring. This approach was used to develop a convenient, high yielding, and stereoselective route to several practically important optically active α-amino substituted benzocyclic compounds. 相似文献
8.
G. I. Borodkin I. R. Elanov R. V. Andreev M. M. Shakirov V. G. Shubin 《Russian Journal of Organic Chemistry》2006,42(3):406-411
The reaction of [2.2]paracyclophane with nitrosonium tetrachloroaluminate was studied by NMR (1H, 13C) spectroscopy using deuterium isotopic perturbation technique. The resulting cationic complexes containing one and two nitrosonium ions are involved in fast (on the NMR time scale) interconversion. Quantum-chemical calculations performed on the DFT level (using triple zeta basis set) indicate the higher stability of 2η single-charged π-complexes relative to σ complexes corresponding to the addition of NO+ ion at the ipso and ortho positions. The formation of the single-charged π-complex is energetically more favorable, compared to the double-charged π-complex. The affinity of NO+ for [2.2]paracyclophane is much greater than for p-xylene, presumably due to stacking interaction between the aromatic rings in the π-complex. 相似文献
9.
I. S. Vasil’chenko T. E. Shestakova V. N. Ikorskii T. A. Kuz’menko V. G. Vlasenko L. N. Divaeva A. S. Burlov A. I. Uraev I. V. Pirog G. S. Borodkin P. B. Chepurnoi I. G. Borodkina O. A. Beletskii O. A. Karpov I. E. Uflyand A. D. Garnovskii 《Russian Journal of Coordination Chemistry》2007,33(3):176-183
Azomethine derivatives of 1-amino-2-thiobenzimidazole (H2L) were synthesized and studied by IR and 1H NMR spectroscopy. Thiobenzimidazoline tautomeric form of these compounds was found to predominate in a solid state and DMSO solution. Novel mono-and binuclear metal chelates M(HL)2 and M2L2 (M = Ni(II), Cu(II), Co(II), Zn(II), Cd(II)) were synthesized on the basis of H2L derivatives and their composition and structures were established from IR, 1H NMR, EXAFS, and magnetochemical data. The composition of coordination sphere was shown to produce no effect on ferromagnetic exchange in binuclear Cu(II) complexes. 相似文献
10.
Leonid B. Krivdin Gennady A. Kalabin Raisa N. Nesterenko Boris A. Trofimov 《Tetrahedron letters》1984,25(42):4817-4820
A positive contribution of more than 7 Hz to the direct 13C-13C spin-spin coupling constants induced by the proximity of the nitrogen lone pair in syn-orientation to the coupled nuclei allows an unambiguous configuration assignment of diverse oximes. 相似文献