Competing processes in the condensation of diethyl ethoxymethylidenemalonate and malononitrile derivatives with CH acids containing a thiocarbamoyl group

Diethyl ethoxymethylidenemalonate and ethoxymethylidenemalononitrile react with CH acids containing a thiocarbamoyl group along several concurrent pathways to give both acyclic structures and pyridine and pyrimidine derivatives.     

Reaction of polyfluorocarbonyl compounds with 8-hydroxyquinolines

It was shown that polyfluorocarbonyl compounds at 25°C in aprotic solvents readily C-alkylate 8-hydroxy- and 5-methyl-8-hydroxyquinolines. Selectivity was observed toward substitution at position 7 by nitropentafluoro- and hexafluoroacetones and at position 5 of 8-hydroxyquinoline by the methyl ester of trifluoropyruvic acid.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2786–2789 December, 1989.     

Particle size,morphology, and properties of transition metal ferrospinels of the MFe<Subscript>2</Subscript>O<Subscript>4</Subscript> (M = Co,Ni, Zn) type,produced by glycine-nitrate combustion

Ferrites-spinels of the MFe₂O₄ type (M = Co, Ni, Zn), produced by glycine-nitrate combustion were studied. A physicochemical study of ferrite samples was performed by X-ray fluorescence analysis, scanning electron microscopy, X-ray phase analysis, and X-ray spectroscopy. The average size of the coherent scanning region was found to be (nm): 28 ± 2 for CoFe₂O₄, 32 ± 2 for NiFe₂O₄, and 26 ± 2 for ZnFe₂O₄. Magnetic characteristics were determined by the NMR method. The specific residual magnetization, specific saturation magnetization, and coercive force were, respectively, 14.1 A m² kg^?1, 20.1 A m² kg^?1, 31800 A m^?1 for CoFe₂O₄; 4.4 A m² kg^?1, 23.1 A m² kg^?1, 6550 A m^?1 for NiFe₂O₄; and 5.1 A m² kg^?1, 18.3 A m² kg^?1, 3200 A m^?1 for ZnFe₂O₄. Their magnetic properties show that the resulting ferrospinel powders can be used in the following fields of technology: CoFe₂O₄ in those areas where heat transfer is necessary (hyperthermia) and in development of data storage media; NiFe₂O₄ and ZnFe₂O₄ in those areas where low heat exchange is necessary, ZnFe₂O₄ for fast remagnetization and NiFe₂O₄ as a core or shell for transportation of other substances. The ferrospinel samples compare well in magnetic properties with their foreign commercial analogs, which makes these compounds commercially viable.     

Unexpected synthesis and crystal structure of ethyl 3-benzoyl-2,6-bis(2-chlorophenyl)-1-cyano-4-hydroxy-4-phenylcyclohexane-1-carboxylate

Three-component condensation of dibenzoylmethane with o-chlorobenzaldehyde and cyanoacetamide in the presence of piperidine gave ethyl 3-benzoyl-2,6-bis(2-chlorophenyl)-1-cyano-4-hydroxy-4-phenylcyclohexane-1-carboxylate. The molecular and crystal structures of the product were studied by X-ray analysis.     

New synthetic method for functionally substituted morpholinium 1,4-dihydropyridine-2-thiolates and their derivatives

By condensation of aromatic aldehydes with cyanothioacetamide and enamines of 1,3-dicarbonyl compounds functionally substituted morpholinium 1,4-dihydropyridine-2-thiolates were obtained applied to the synthesis of 2-alkylsulfanyl-1,4-dihydropyridines, 1,4-dihydrothieno[2,3-b]-pyridines, and 2,3,4,7-tetrahydrothiazolo[3,2-a]pyridine.     

Aliphatic aldehydes in the synthesis of condensed 4-alkyl(cycloalkyl)-2-amino-3-cyano-4H-pyrans

Substituted 4-alkyl(cycloalkyl)-2-amino-3-cyano-4H-pyrans have been obtained from the reaction of aliphatic aldehydes with malononitrile and some other CH acids in the presence of N-methylmorpholine. T. G. Shevchenko Lugansk State Pedagogical University, Lugansk 348011, Ukraine. N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow 117813, Russia; Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, 1363–1366, October, 1999.     

Spin-peierls transition in dimerized stacks of anion-radical salt (N-Me-2,5-di-Me-Pz)(TCNQ)2, (Pz is pyrazine)

An anion-radical salt (ARS) (N-Me-2,5-di-Me-Pz)(TCNQ)₂, where Pz is pyrazine, was synthesized and its crystal structure was resolved. X-ray diffraction experiments on single crystals were performed. Heat capacity was measured in the temperature range from 2 to 300 K. Magnetisation and magnetic susceptibility were measured in the temperature range from 2 to 300 K and the low-temperature part was measured in magnetic fields from 5 mT to 5 T. The experimental results were explained in terms of dimerized Heisenberg spin chain model. Numerical calculations were performed and compared with experimental data.     

Reaction of polyhaloalkyl-substituted chromones, pyrones, and furanones with salicylaldehydes as a direct route to fused 2H-chromenes

Polyhaloalkyl-substituted chromones, gamma-pyrones, and beta-furanones react with salicylaldehydes in the presence of piperidine to give a wide variety of fused 2H-chromenes in good yields. This novel annulation reaction presumably proceeds by a tandem intermolecular oxa-Michael addition and subsequent intramolecular Mannich condensation.