Reactions of aroylpyruvic acids withS-methylisothiosemicarbazide hydroiodide and studies of the crystal structures of the reaction products

The reactions ofp-chlorobenzoyl- and benzoylpyruvic acids withS-methylisothiosemicarbazide hydroiodide gave 3-methylthio-6-(p-chlorophenacyl)-2,5-dihydro-1,2,4-triazin-5-one and 6-phenacyl-2,3,4,5-tetrahydro-1,2,4-triazine-3,5,-dione, respectively. The molecular and crystal structures of the compounds synthesized were studied by X-ray diffraction analysis. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 704–708, April, 1998.     

Interaction of 3-Chloro-2-halopropenyl Ketones with β-Aminocrotonic Acid Ethyl Ester

The reaction of 3-chloro-2-halo-1-propenyl ketones with β-aminocrotonic acid ethyl ester leads to the formation of ethyl esters of 6-alkyl(aryl, benzyl, cyclohexyl)-4-chloromethyl-2-methylnicotinic acids. It was established that at increased temperatures the compounds obtained are partially converted into the corresponding dihydrofuro[3,4-c]pyridines. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1184–1188, August, 2005.     

Mass-spectrometric an EPR studies of methane interaction with Re?Al?O oxide catalysts

The effect of oxidative-reductive pretreatment of Re–Al–O catalysts on their activity in methane aromatization has been established. Paramagnetic centers have been identified and their contribution to the conversion of methane into benzene over these catalyst is discussed.

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- Re–Al–O . .

     

Complex formation of copper(II) and nickel(II) with N-arylthiopicolinamides

The reactions of N-arylthiopicolinamides (HL) with copper(II) and nickel(II) ions in organic and aqueous-organic solutions were studied. On addition of HCl, the transformation of ML₂ complexes into M(HL)Cl₂ occurs, while the reverse reaction takes place under the action of amphoteric protic solvents. The structures of the isolated complexes were established by IR and UV spectroscopy.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1546–1550, September, 1993.     

Determination of the orientation of the phenyl substituent in isomeric 1-ethyl-2,5-dimethyl-4-phenyl-4-piperidinols by two-dimensional nuclear overhauser effect (NOESY) spectroscopy. Conformation of the β isomer of 1,2,5-trimethyl-4-phenyl-4-piperidinol

In the case of three isomers (, , and ) of 1-ethyl-2,5-dimethyl-4-phenyl-4-piperidinol it is shown that NOESY spectroscopy can be successfully used in the determination of the orientation of the phenyl substituent. It was observed that the chemical shifts of the protons and the carbon atoms in the ortho position and of the quaternary C atom of the phenyl substituent and the , direct spin-spin coupling constant (SSCC) satisfactory reflect the change in the orientation of the phenyl substituent on passing from the a isomer to the and isomers. A chair 2a5e) twist-boat (2e, 5e) conformational equilibrium in which the twist-boat conformation is stabilized by an intramolecular hydrogen bond is proposed for the isomer of 1,2,5-trimethyl-4-phenyl-4-piperidinol on the basis of the NMR data.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1069–1072, August, 1990.     

Synthesis and Crystal and Molecular Structure of 3,5-Dihydroxy-1-diphenylmethyleneamino-5-methoxycarbonyl-4-p-toluoyl-2,5-dihydro-2-pyrrolone

The reaction between methyl 2-diphenylmethylenehydrazino-4-oxo-4-p-tolyl-2-butenic ether and oxalyl chloride gave 1-diphenylmethyleneamino-5-methoxycarbonyl-4-p-toluoyl-2,3-dihydro-2,3-pyrroledione, which adds water to yield substituted 3,5-dihydroxy-2,5-dihydro-2-pyrrolone. The crystal and molecular structure of pyrrolone and the inter- and intramolecular hydrogen bonds in its crystals and solutions were investigated by IR spectroscopy and XRD analysis. The crystals of C₂₇H₂₂N₂O₆ are triclinic with cell dimensions a = 9.8540(10), b = 10.0880(10), c = 13.982(2) , = 69.820(10), = 110.57(10), = 91.350(10)°, V = 1213.8(2) ³, M = 470.47, d _calc = 1.287 g/cm³, Z = 2, space group P1. The data were collected on a KM-4 (KUMA DIFFRACTION) diffractometer, 3781 reflections with I> 2 (I). Direct methods, hydrogen atoms localized, least-squares refinement (in an anisotropic approximation for non-hydrogen atoms), R = 0.0454. The crystal is built from the centrosymmetric dimer associates of molecules bonded by strong (2.64 ) intermolecular hydrogen bonds (IMHB) of O–H...O type. The dimer associates are linked by weaker (2.82 ) centrosymmetric IMHB, forming an infinite chain of hydrogen-bonded molecules.     

HSAB principle and desulphuration reaction during ionic coordination polymerization of thiiranes [1]

Desulphuration of trimethylthiirane (TMT), catalyzed by anionic and cationic catalysts for thiirane polymerization, has been studied. The possibility of obtaining polymers having mono-, di- and trisulphide bonds during TMT polymerization by typical cationic catalysts has been shown. Some peculiarities of the desulphuration reaction during the polymerization of thiiranes by ionic catalysts have been found. Differences in their catalytic action, shown by the formation of different quantities of both disulphide SSbonds in polymer chain and alkene, are discussed from the point of view of HSAB principle and symbiotic effect of ligands at the counterion. It is shown that desulphuration reactions during the cationic and anionic polymerization of thiiranes have a similar electronic nature, consisting of increase of coordinative state and the activation of the acceptor orbital of the thiirane sulphur atom. The nucleophilic attack by thiirane (during cationic polymerization) or growing thiolate-ion (during anionic polymerization) on the electrophilic sulphur atom of thiiranium intermediates

respectively, is accompanied by concerted fragmentation of these intermediates, giving the alkene and disulphide fragment. Possible mechanisms have been suggested for thiirane desulphuration and SSbond formation in products of the ionic polymerization of thiiranes. HSAB principle proved to be very useful for discussion of experimental results and other aspects of thiirane polymerization.     

Crystal and molecular structure of 2,2′-bis[2-(p-dimethylaminophenyl)indane-1,3-dione] displaying mechanochromic properties

Institute of Chemical Physics, Academy of Sciences of the SSSR. Institute of Physiologically Active Compounds, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 31, No. 5, pp. 103–107, September–October, 1990.     

Diazocarbonyl derivatives of heterocycles. 7. Synthesis,properties, and structure of 2,4-diazido-6-diazoacetylpyrimidine

The reaction of 2,4-dichloro-6-diazoacetylpyrimidine with sodium azide to give 2,4-diazido-6-diazoacetylpyrimidine has been examined, and the crystal structure of the latter, and its 1,3-dipolar cycloadditions at the carbonyl group, studied.For Communication 6, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 515–519, April, 1990.