Condensed imidazo-1,2,4-azines. 14. Synthesis and reactivity of 3-chlorine-substituted imidazo[1,2-b]-1,2,4-triazines

When boiled with phosphorus pentachloride in phosphorus oxychloride, 2-methyl-6-phenyl-imidazo[1,2-b]1,2,4-triazin-4H-3-one gives a mixture of mono- and dichloro derivatives, whereas the action of thionyl chloride in chloroform with a catalytic amount of DMFA gives only the monosubstituted product 2-methyl-3-chloro-6-phenylimidazo[1,2-b]-1,2,4-triazine. The reactivity of the 3-chloro derivatives of imidazo[1,2-b]-1,2,4-triazine in reactions with diethylamine, piperidine, morpholine, aniline, hydrazine hydrate and thiourea was investigated.For Communication 13, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 981–985, July, 1986.     

Effects of acids on orientation in the reaction of 5-formyl-4-(1-pyridino)azole 2-oxides with aromatic amines

Azole betaines containing vicinal formyl and pyridinium groups react with aromatic amines to give, when protonated by weak or strong acids, azolidine-2,4-dione-5-aldehyde azomethines (I) or 4-aryliminoazolidin-2-ones (II), respectively. Compound (I) is formed by the intramolecular migration of the oxygen in the 4-position of the azole, and (II) by decarbonylation of the original betaine. The orientation in the reaction of dicentric nucleophiles (hydrazines and o-phenylenediamine) is independent of the extent of protonation, giving betaine hydrazones and azolo[4,5-b]benzodiazepines, respectively. The PMR mass spectra of the products are discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 233–238, February, 1986.     

Electrophilic and nucleophilic substitution in oxazolo[3,2-f]xanthines

Bromination of 2-aryloxazolo[3,2-flxanthines gives the 3-bromoderivatives whereas 8-methyl-2-phenyloxazolo[3,2-f]xanthine is nitrated in the para-position of the phenyl substituent. Alkylation of oxazolo[3,2-f]xanthines by ethylmonoiodoacetate gives the ethyl esters of oxazolo[3,2-f]xanthinyl-6-acetic acids. Reaction of oxazolo[3,2-f]xanthines with sodium sulfide gives thiazolo[3,2-f]xanthines whereas the reaction with secondary amines opens the oxazole ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1396–1399, October, 1990.     

Cyclization of n-alkylazinium cations with bisnucleophiles. 5. Cyclic adducts and recyclization products in the reactions of benzodiazinium cations with imido esters

The reaction of imido esters that contain an active methylene group with four isomeric benzodiazinium cations, viz., the 1-methylquinoxalinium, 2-methylcinnolinium, 3-methylquinazolinium, and 2-methylphthalazinium cations, was investigated. The 1-methylquinoxalinium cation reacts with imido esters via a scheme involving anionic [3^– +2]-cycloaddition to form tetrahydropyrrolo[2,3-b]quinoxalines. The 2-methylcinnolinium cation forms an adduct with an annelated pyrrole ring. Under the influence of imido esters, the 3-methylquinazolinium cation undergoes recyclization to a 2,3-disubstituted quinoline. The 2-methylphthalazinium cation is inert in this reaction.See [1] for Communication 4.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1549–1553, November, 1981.     

Transformations of the sulfur analogs of Β-carbolins under the influence of nucleophiles

The reaction of the quaternary salts of some thienopyridines (the sulfur analogs of -carbolins) with nucleophilic reagents was investigated. It was shown that either the methylene anhydro bases are formed or one or both heterocyclic rings are transformed, depending on the structure of the thienopyridine and on the reaction conditions.For the previous communication, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 398–403, March, 1987.     

Microwave and ultrasonic extraction of chlorophenoxy acids from soil and their determination by fluorescence polarization immunoassay

Procedures were developed for the ultrasonic and microwave extraction of pesticides, 2,4-dichlorophenoxyacetic (2,4-D) and 2,4,5-trichlophenoxyacetic (2,4,5-T) acids from soils for the subsequent determination by fluorescence polarization immunoassay (FPIA). The effect of the matrix composition of soils on the FPIA results was studied, and the optimum extractants and extraction conditions were selected. It was found that 40% ethanol is optimum for both extraction and FPIA determination, because it does not cause antibody denaturation. The recovery of pesticides in soil was 80–132% for 2,4-D and 101–138% for 2,4,5-T. Microwave extraction is more efficient than ultrasonic extraction for the determination of 2,4-D and 2,4,5-T in soil. The detection limit in soil and the analytical range are 2 and 4–200 μg/g, respectively, for 2,4-D and 20 and 80–5000 μg/g, respectively, for 2,4,5-T. Results of the determination of 2,4-D in soil by FPIA are in good agreement with the results of the determination by high-performance liquid chromatography. The procedures can be used for the rapid determination of chlorophenoxy acids in soils.     

Effect of solvent nature on the catalytic activity of iron-containing pyrocatecholsulfonic cationite in the reactions of H<Subscript>2</Subscript>O<Subscript>2</Subscript> decomposition and benzene hydroxylation

Kinetics of hydrogen peroxide decomposition under the conditions of heterogenous catalysis with iron-containing pyrocatecholsulfonic cationite at 50°C in dimethyl sulfoxide, tetrahydrofuran, dioxane, acetonitrile, and nitromethane was studied. The value of rate constant of hydrogen peroxide decomposition in these solvents was found to diminish with increase of solvent nucleophilicity. At the hydroxylation of benzene in the aqueous acetonitrile medium the formation of phenol was observed. The phenol yield was found to depend on the composition of the binary solvent acetonitrile-water.     

Modifications in structure of palladium(II) porphinate as a method of regulating the catalysis of hydrogen peroxide decomposition

Results of kinetic, volumetric, and spectral study of the reaction of alkaline H₂O₂ decomposition in a water-dimethyl formamide medium catalyzed by Pd^IIP_f (P_f is octaethylporphyrin and its monophenyl-, 5,15-diphenyl-, 5,10-diphenyl-, triphenyl-, and tetraphenyl-substituted in meso-positions derivatives) under polythermal conditions are presented. It was found that the catalysis is of the heterogeneous nature; intermediates and complete kinetic characteristics (rates, activation parameters, and the orders with respect to all reagents) were determined depending on the macrocycle structure. The sequence of the catalytic activity of palladium(II) porphyrinates was estimated.     

Reductive amination of carbonyl compounds in the presence of cobalt and rhodium complexes

Summary The reductive amination of carbonyl compounds in the presence of some cobalt and rhodium complexes has been studied, The selectivity and efficiency of the process is discussed using the interaction of cyclohexanone with ammonia as an example. The possible mechanism for the reaction is considered.Abbreviation DMG dimethylglyoxime - IDSA indigodisulphoacid - Fl flourescein - DBG dibenzylglyoxime     

Condensed imidazo-1,2,4-azines. 11. The reaction of 2,6-diphenylimidazo[1,2-b]-1,2,4-triazine with formaldehyde

The structure of four main products contained in the reaction mixture obtained in the oxymethylation of 2,6-diphenylimidazo[1,2-b]-1,2,4-triazine was established by the method of chromato-mass spectrometry, with the enlistment of PMR spectroscopy.Translated from Khimiya Geterostiklicheskikh Soedinenii, No. 11, pp. 1565–1568, November, 1984.