Synthesis and Structure of a New Ruthenium(II) Clathrochelate and the Use of a Highly Porous Ceramic Material with an Immobilized Complex in the Oxidative Conversion of Methane

Kinetics and Catalysis - A new ruthenium(II) cage complex with polar terminal groups in the apical substituents has been synthesized; the molecular design of the complex contributes to the...     

Synthesis,methylation, and acylation of 1,2-dihydrodeoxyvasicinones and their homologs

2,3-Trimethylene- and 2,3-pentamethylene-1,2,3,4-tetrahydro-4-quinazolones and their 6-methyl and 6-bromo derivatives have been obtained by the reduction of deoxyvasicinone and its 6-methyl and 6-bromo derivatives and also their seven-membered homologs at the cycloalkane ring with sodium tetrahydroborate in ethanol. The alkylation and acylation reactions of the above-mentioned reducing compounds have been studied. Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 659–663, September–October, 1990.     

Reaction of Chloro(chlorodimethyl)dimethylsilane with O-Silylurethanes and Nicotinic Hydrazide in the Presence of Hexamethyldisilazane

The reaction of chloro(chlorodimethyl)dimethylsilane and hexamethyldisilazane with O-silylurethanes and nicotinic hydrazide gives rise to products whose structure is determined by the composition, structure, and basicity of intermediate compounds. The reaction allowed synthesis of previously unknown linear and heterocyclic compounds.     

Electron diffraction study of the structure of the NbOF3 molecule

Simultaneous electron diffraction and mass spectrometric study of vapor over hydrolyzed NbF₅ was carried out. Conditions providing the presence of niobium oxytrifluoride in the gas phase have been revealed, and structural parameters of the NbOF₃ molecule, corresponding to the r_α configuration of C_3v symmetry, have been determined: r_α(Nb=O) 1.688(7), Å; r_α(Nb-F) 1.861(4) Å; r_α(O-F) 2.857(23) Å; r_α(F-F) 3.079(22) Å; ∠_α(O-Nb-F) 107.1(1.5)^o; ∠_α(F-Nb-F) 111.6(1.4)^o. Ivanovo State Chemical Technological Academy. Ivanovo State University. Translated fromZhumal Struktumoi Khimii, Vol. 37, No. 4, pp. 708–715, July–August, 1996. Translated by L. Smolina     

Application of IR spectroscopy in the analysis of the woody-fibrous mass in the process of hydrolysis

The possibility has been shown of using IR spectroscopy in the investigation of the changes in the polysaccharide component of wood in the process of acid hydrolysis. The method of determining the relative optical density (ROD) was used for the quantitative evaluation of the changes in the functional groups of the lignocellulose.Deceased.Siberian Scientific Research Institute of Cellulose and Board, Bratsk. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 683–687, September–October, 1990.     

Study of the nucleophilic substitution reactions of 2,4,10-trichloropyrimido[5,4-b]quinoline

A number of pyrimido[5,4-b]quinoline derivatives were synthesized. It is shown that in the reaction of 2,4,10-trichloropyrimido[5,4-b]quinoline (II) with strong nucleophilic reagents (OCH₃ and SH) both of the halogens of the pyrimidine ring are replaced, while with amines substitution of the halogens of the pyrimidine ring proceeds successively; under more severe conditions, all three halogen atoms of II are replaced by amine residues.     

Kinetics and mechanism of nitration of cellulose with the HNO3-CH2Cl2 mixture

Complexing in the HNO₃-CH₂Cl₂ system was confirmed tensimetrically. The kinetics of nitration of wood cellulose by the HNO₃-CH₂Cl₂ mixture were investigated. A large part of the cellulose is nitrated in a first fast reaction in comparison to the HNO₃-H₂SO₄ mixture with the same concentration of HNO₃. The rate of the process is determined by the rate of diffusion of the HNO₃, the rate of the process decreases more rapidly in the case of HNO₃-CH₂Cl₂ than in the HNO₃-H₂SO₄ mixture, which is probably due to the effect of CH₂Cl₂ on the diffusion coefficient of HNO₃.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2445–2450, November, 1989.     

Investigation of the structure and energetics of β-diketonates. II. Structure of the bis-dipivaloylmethanatocopper(II) molecule by gas phase electron diffraction

Ivanovsk State University. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 6, pp. 76–83, November–December, 1992.     

5-Aminoorotic acid derivatives

The 2,4,8-trioxo derivative of pyrimido[5,4-d][1,3]oxazine was synthesized, and esters and amides of 5-acetamidoorotic acid were obtained from it. The acetyl group in 5-acetamido-orotic acid esters is readily hydrolyzed in acidic media to give esters of 5-aminoorotic acid, while the acetyl group in amides of 5-acetamidoorotic acid do not undergo hydrolysis.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 270–272, February, 1973.Deceased.     

Gas electron diffraction study of the molecular structure of NbCl4

The structure of the NbCl₄ molecule is studied experimentally by the synchronous electron diffraction and mass spectrometry methods. The model molecular geometries of C_2v, C_3v, D_2d, and T_d symmetries are verified. The advantages of the tetrahedral model over the other models are established. The thermally averaged parameters of the effective configuration of the NbCl₄ molecule are as follows: r_g(Nb?Cl)=2.279(5) Å, l(Nb?Cl)=0.073(2) Å, r_g(Cl?Cl)=3.692(17) Å, l(Cl?Cl)=0.275(11) Å, ∠_g(Cl-Nb-Cl)=108.2(5)°, and δ(Cl?Cl)=0.030(19) Å.