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341.
Khrustalev VN Chernov OV Aysin RR Portnyagin IA Nechaev MS Bukalov SS 《Dalton transactions (Cambridge, England : 2003)》2008,(9):1140-1143
A new trioxystannate-transition metal complex, {[Li][(Me(2)NCH(2)CH(2)O)(3)Sn-Fe(CO)(4)]}(2) (3), exhibiting an unusual type of the heteronuclear bonding between heavier Group 14 elements and transition metals, has been synthesised and completely characterised by NMR, Raman and IR spectroscopy in solution as well as by Raman spectroscopy and X-ray diffraction analysis in the solid state. 相似文献
342.
V. I. Maleev Z. T. Gugkaeva A. T. Tsaloev M. A. Moskalenko V. N. Khrustalev 《Russian Chemical Bulletin》2012,61(1):51-58
The amide and sulfamide derivatives of (1R,2R)-N,N-diethylcyclohexane-1,2-diamine can serve as organocatalysts for addition of Me3SiCN and Et2Zn to aldehydes. 相似文献
343.
F.?I.?ZubkovEmail author E.?V.?Nikitina V.?P.?Zaytsev V.?N.?Khrustalev R.?A.?Novikov R.?S.?Borisov A.?V.?Varlamov 《Chemistry of Heterocyclic Compounds》2012,48(5):785-794
On the basis of a transition state conformation analysis, an attempt was made to explain the high chemoselectivity of intramolecular [4 + 2] cycloaddition in 3-alkyl-2,6-difuryl-N-maleylpiperidin-4-ones. It was shown that the thermal Diels–Alder reaction in these piperidine derivatives takes place through the “boat” conformation and leads to the formation of hydrogenated 1-alkyl-4-(2-furyl)-2H-8,10a-epoxy-pyrido[2,1-a]isoindol-2-ones. The alternative regioisomers, 3-alkyl-4-(2-furyl)-2H-8,10a-epoxy-pyrido[2,1-a]isoindol-2-ones, are hardly formed at all. At the same time, the intramolecular Diels–Alder reaction in the isostructural 3-alkyl-N-allyl-2,6-difurylpiperidin-4-ones, takes place non-regioselectively from the “chair” conformation. 相似文献
344.
V. P. Ananikov A. O. Piroyan K. A. Gaiduk I. P. Beletskaya V. N. Khrustalev M. Yu. Antipin 《Russian Journal of Organic Chemistry》2009,45(12):1743-1754
Stable 1,2-disulfanylalkene palladium complexes [(RS-CH=CR′-SR)PdCl2] were synthesized in 85–94% yield by reaction of palladium(II) chloride with sulfur-containing ligands RS-CH=C(R′)-SR (analogs
of dithiolate ligands). The structure of the complexes was studied by NMR spectroscopy and quantum-chemical methods. The binding
energy in palladium complexes with bis(arylsulfanyl)- and bis(alkylsulfanyl)alkenes was estimated (DFT) at 50 and 56 kcal/mol,
respectively. Variation of substituents on the sulfur atoms is a convenient tool for fine tuning of the ligand properties
and controlling the strength of the complex. The bite angle of the ligands does not depend on the substituent nature and is
88–89°, which is typical of square-planar complexes. According to the bite angle, the examined ligands are analogs of well
known bidentate phosphine ligands, but the former are more labile since the corresponding binding energy is lower by 36 kcal/mol. 相似文献
345.