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Shainyan B.A.,Favorsky Irkutsk Institute of Chemistry | Kleinpeter E.,University of Potsdam
Tetrahedron | Year: 2013

Stereochemical studies on silaheterocyclohexanes is a 'hot topic' as evidenced by the growing number of publications. During last 10 years a substantial number of substituted silacyclohexanes and heterocyclohexanes containing sulfur, oxygen or nitrogen as the second (or third) heteroatom have been synthesized and studied by variable temperature dynamic NMR spectroscopy, gas-phase electron diffraction, variable temperature IR, Raman, microwave spectroscopy with respect to thermodynamic (frozen conformational equilibria) and kinetic (barrier to ring inversion) information. As the stereochemistry of cyclohexane and its N-, O-, P-, S-hetero analogues is one of keystones of modern theoretical and synthetic organic and heterocyclic chemistry, the stereochemistry of silacyclohexane and its hetero analogs is an important element of theoretical and synthetic organosilicon chemistry. The various classes of saturated six-membered rings were critically compared and studied in detail with respect to differences in their stereochemistry and dynamic behavior. © 2013 Elsevier Ltd. All rights reserved.


Rusakov Yu.Yu.,Favorsky Irkutsk Institute of Chemistry | Krivdin L.B.,Favorsky Irkutsk Institute of Chemistry
Russian Chemical Reviews | Year: 2013

The modern quantum chemical methods for calculating spin-spin coupling constants in NMR spectra are reviewed. The theoretical basis of these methods and author's vision of the prospects of their development and practical applications in structural and stereochemical studies are presented. The bibliography includes 288 references. © 2013 Russian Academy of Sciences and Turpion Ltd.


Shainyan B.A.,Favorsky Irkutsk Institute of Chemistry | Kleinpeter E.,University of Potsdam
Tetrahedron | Year: 2012

The conformational equilibria of 1-phenyl-1-silacyclohexane 1, 3-phenyl-1,3-thiasilacyclohexane 2, 1-methyl-1-phenyl-1-silacyclohexane 3, and 3-methyl-3-phenyl-1,3-thiasilacyclohexane 4 have been studied for the first time by low temperature 13C NMR spectroscopy at 103 K. Predominance of the equatorial conformer of compound 1 (Ph eq/Ph ax=78%:22%) is much less than in its carbon analog, phenylcyclohexane (nearly 100% of Ph eq). And in contrast to 1-methyl-1-phenylcyclohexane, the conformers with the equatorial Ph group are predominant for compounds 3 and 4: at 103 K, Ph eq/Ph ax ratios are 63%:37% (3) and 68%:32% (4). As the Si-C bonds are elongated with respect to C-C bonds, the barriers to ring inversion are only between 5.2-6.0 (ax→eq) and 5.4-6.0 (eq→ax) kcal mol -1. Parallel calculations at the DFT and MP2 level of theory (as well as the G2 calculations for compound 1) show qualitative agreement with the experiment. The additivity/nonadditivity of conformational energies of substituents on cyclohexane and silacyclohexane derivatives is analyzed. The geminally disubstituted cyclohexanes containing a phenyl group show large deviations from additivity, whereas in 1-methyl-1-phenyl-1-silacyclohexane and 3-methyl-3-phenyl-1,3-thiasilacyclohexane the effects of the methyl and phenyl groups are almost additive. The reasons for the different conformational preferences in carbocyclic and heterocyclic compounds are analyzed using the homodesmotic reactions approach. © 2011 Elsevier B.V. All rights reserved.


Gusarova N.K.,Favorsky Irkutsk Institute of Chemistry | Arbuzova S.N.,Favorsky Irkutsk Institute of Chemistry | Trofimov B.A.,Favorsky Irkutsk Institute of Chemistry
Pure and Applied Chemistry | Year: 2012

The use of novel general halogen-free methodology for the synthesis of phosphines, phosphine chalcogenides, and phosphinic acids from elemental phosphorus and alkenes and alkynes in the superbase suspensions is described. © 2012 IUPAC.


Rulev A.Y.,Favorsky Irkutsk Institute of Chemistry
Russian Chemical Reviews | Year: 2011

Data published in the last 10 years on the use of the aza-Michael reaction in organic synthesis are described systematically. The attention is focused on environmentally friendly processes following green chemistry principles and on methods for the synthesis of compounds that are difficult to access by other routes. The bibliography includes 269 references. © 2010 Russian Academy of Sciences and Turpion Ltd.


Shainyan B.A.,Favorsky Irkutsk Institute of Chemistry | Tolstikova L.L.,Favorsky Irkutsk Institute of Chemistry
Chemical Reviews | Year: 2013

Trifluoromethanesulfonamide and its various N-substituted derivatives may strongly affect the reactivity as compared to the alkyl- or arylsulfonamides. This is clearly exemplified by the reactions of condensation, the inertness of triflamide to strong electrophiles that easily react with other sulfonamides, the different courses of the reactions with alkenes in the same oxidative system (t-BuOCl + NaI), and other specific patterns of reactivity demonstrated by triflamide and its analogues. Two principal synthetic approaches to triflamides and other perfluoroalkylsulfonamides are the reaction of the corresponding fluoroalkylsulfonyl fluorides RFSO2F with ammonia or amines. Structurally, considering the planarity of the amino group, triflamides are intermediate between carboxamides and nonfluorinated sulfonamides. N,N-Dichlorotriflamide, the sodium salt of N-chlorotriflamide, and their higher perfluorinated analogues act as imination reagents with respect to sulfides, sulfoxides, phosphines.


Rusakova I.L.,Favorsky Irkutsk Institute of Chemistry | Krivdin L.B.,Favorsky Irkutsk Institute of Chemistry
Physical Chemistry Chemical Physics | Year: 2013

A double perturbation theory (DPT) at the second order level of approximation formalism has been applied to examine the dihedral angle dependence of the Fermi-contact (FC) contribution to nuclear spin-spin coupling constants. The unperturbed wave function of the ground state in DPT was approximated by the Hartree-Fock Slater determinant, while the excited states were treated as the single excited determinants. An analytical expression relating the FC term of vicinal proton-proton spin-spin coupling constants across the aliphatic single carbon-carbon bond to the dihedral angle describing inner rotation around the C-C bond in the ten-electron ten-orbital moiety H-C-C-H has been derived and analyzed. In particular, it has been shown that extrema of 3J(H,H) are observed at φ = πn, n = 0, ±1, ±2,..., which provides a theoretical background of a well-known semiempirical Karplus equation. © 2013 the Owner Societies.


Lazareva N.F.,Favorsky Irkutsk Institute of Chemistry
Russian Chemical Bulletin | Year: 2011

The data on biological activity of the compounds with the geminal fragment N-C-Si are systematized. The examples of using N-(silylmethyl)amines and related compounds in syntheses of biologically active substances, including natural compounds, are considered. © 2011 Springer-Verlag.


Kirpichenko S.V.,Favorsky Irkutsk Institute of Chemistry | Shainyan B.A.,Favorsky Irkutsk Institute of Chemistry
Tetrahedron | Year: 2015

A new facile and efficient one-pot procedure for the synthesis of 3-phenyl-3-silatetrahydropyrans with an easily functionalized Si-Ph bond was developed. The method is based on the intramolecular cyclization of chloromethyl(3-hydroxypropyl)phenylsilanes using the n-Bu4NBr/i-Pr2NEt combination. As an example of functionalization, the synthesis of the first 3-silatetrahydropyran with an exocyclic RO-Si bond is reported. © 2014 Elsevier Ltd.


Grant
Agency: European Commission | Branch: FP7 | Program: CP | Phase: ENERGY.2008.10.1.2;NMP-2008-2.6-1 | Award Amount: 3.47M | Year: 2009

Current battery technologies for hybrid (HEVs) and small electric vehicles (EVs) have technological, cost or environmental limitations. Despite this, the global market for HEVs and EVs is growing rapidly and is expected to top $2billion by 2015. The PolyZion project will create a new class of fast rechargeable zinc-polymer battery for hybrid and small electric vehicle applications. The research programme combines fundamental material and process advances in ionic liquids, rechargeable zinc electrodes, ultra-fast pulse charge injection techniques and conducting polymers, as well as constructing prototypes battery units for industry standard testing. The resulting battery device will be low cost, have low environmental impact and have the energy and power density necessary to compete will alternative battery technologies inthe HEV and EV markets. PolyZion is a European-led consortium combining world-class research organisations in ionic liquids, conducting polymers, zinc deposition, pulse charging and batteries, as well as SME partners with expertise in technology development and specialised materials, and large industrial partners with industrial experience of battery manufacture and state-of-the-art testing facilities. The consortium also includes 2 organisations with world-class research expertise from an Emerging Economy (Russia) and a High Income (Canada) countries outside the EU.

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