To the Jubilee of Vsevolod Alekseevich Solonnikov

Bibliography: 42 titles.__________Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 306, 2003, pp. 7–15.     

Weighted estimates of a solution to the linear problem connected with the one-phase Stefan problem in the case where the specific heat tends to zero

We prove estimates in weighted Hölder norms for a solution to the model linear problem related with the one-phase Stefan problem with a small multiplier ε at time derivative in the heat equation. These estimates are uniform with respect to parameter ε and are significant in justification of passage to the limit in the one-phase Stefan problem as the specific heat tends to zero. Bibliography: 8 titles.     

Polarity,polarizability, and structure of esters. 6. Conformations of para-substituted phenyl chloroformates in solutions

The ellipsoid of polarizability of the chloroformate fragment ClC(O)O has principle semiaxes b₁=3.64, b₂=5.34, b₃=3.81 Å₃; the angle between b₁ and the C=0 bond is 24.5°. Aromatic chloroformates in solutions exist in conformations with cisoid position of the C=O and O-R bonds and the phenoxyl fragment in aromatic chloroformates deviates from the plane of the molecule.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2704–2708, December, 1989.The authors wish to thank S. G. Vul'fson for assistance in measuring the depolarization of Rayleigh light scattering.     

Synthesis of 1,11,11-trimethyl-3,6-diazotricyclo [6.2.1.0<Superscript>2,7</Superscript>]undeca-2,6-diene and 1,15,15-trimethyl-3,10-diazotetracyclo[10.2.1.0<Superscript>2,11</Superscript>.0<Superscript>4,9</Superscript>]pentadeca-2,4(9),5,7,10-pentaene from camphoroquinone enantiomers

Optically active camphordihydro-2,3-pyrazine and camphorquinoxaline were prepared from camphoroquinone enantiomers. It was shown that (1S,4R)-(+)-camphoroquinone was formed by oxidation of (1S,3R, 4R)-(−)-3-bromocamphor and (1R,4S)-(−)-camphoroquinone from (1R,3S, 4S)-(+)-3-bromocamphor, respectively. Camphor anhydride was a side product (6–10%) of the reaction. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 50–52, January–February, 2007.     

Novel synthesis of Planococcus citri pheromone

An effective method was proposed for synthesizing (+)-cis-1R-acetoxymethyl-3-isopropenyl-2,2-dimethylcyclobutane, a pheromone of the citrus mealybug, based on ozonolysis of verbenone that led in one step to the key synthon 1R,3S-3-acetyl-2,2-dimethylcyclobutanecarboxylic acid. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 179–180, March–April, 2006.     

Properties of Ce–Zr–La–O nano-system with ruthenium modified surface

Structural peculiarities of Ce–Zr–La–O and Ce–Zr–La–O/Ru samples in mean of catalytic properties are compared. The samples (Ce:Zr = 1:1, La = 10÷30 mol.%, Ru = 1.5 wt.%) were obtained by sol–gel method (X-samples) and co-precipitation (P-samples). It is shown that Ce_0.45Zr_0.45La_0.1O_2−δ/Ru X-samples are characterized by high thermal stability and the highest catalytic activity in partial methane oxidation reaction. According to XRD, BET, FTIR, EPR and XPS data it is concluded that the difference in the samples catalytic activity is caused by various disposition of Ru-containing phase on the support surface. The distinction in the dimension of Ru-containing particles (3D or 2D) is conditioned by structural peculiarities of Ce_0.45Zr_0.45La_0.1O_2−δ and Ce_0.35Zr_0.35La_0.3O_2−δ P- and X-samples.     

Investigation of a problem for the Laplace equation with a boundary condition of a special form in a plane angle

The explicit solution of the equation u=f in a plane infinite angle, satisfying on one side of the angle a Neumann condition and on the other one the condition u/n + hu/r + u= (/r is the tangential derivative, C, 0), is constructed and estimated in weighted Sobolev spaces. The obtained estimates are sharp with respect to the differential order and are uniform with respect to . The construction of the solution reduces to the investigation of a finite difference equation in the complex plane, arising after a Mellin transform.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova Akademii Nauk SSSR, Vol. 182, pp. 149–167, 1990.     

β-Ketoaldehydes in the synthesis of 6-alkyl-3-cyano-2(1H)-pyridinethiones

An efficient synthesis of 6-alkyl-3-cyano-2(1H)-pyridinethiones by the reactions of the sodium salts of -ketoaldehydes with cyanothioacetamide was developed. Pyridinethiones undergo selectiveS-alkylation with haloacetonitriles and haloacetophenones followed by cyclization to the corresponding thieno[2,3-b]pyridines.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 727–731, April, 1995.This study was financially supported by the Russian Foundation for Basic Research (Project No. 94-03-08-823).     

Synthesis of 4,5,6-trisubstituted 3-cyanopyridine-2(1H)-thiones based on α-substituted β-diketones

5-Substituted 3-cyano-4,6-dimethylpyridine-2(lH)-thiones were synthesized by the re action of a-substituted -diketones with cyanothioacetamide in the presence of triethyl amine. The compounds synthesized were converted into thieno[2,3-blpyridines by treatment with organic halides and KOH.Translated fromlzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2719–2721, November, 1996.