Evolution of spiral dynamic magnetic domains in Anger states of iron garnet films

Dynamic domain structures in the Anger state of iron garnet films are analyzed by a video micrographic technique. Data are obtained on the evolution of individual spiral domains over the lifetime of each domain. A new mechanism for the destruction of this state is discovered. Pis’ma Zh. éksp. Teor. Fiz. 63, No. 6, 453–456 (25 March 1996)     

Mass spectrometry of nitrogen heterocycles. 4. Mass spectral behavior of triazolo[1,5-a]pyrido[2,3-d]pyrimidines

The electron impact mass spectra of substituted 9-imino- and 9-oxotriazolo[1,5-a]pyrido[2,3-d]pyrimidines were studied. The mass spectral data obtained permitted us to determine the order of the fusion of the triazole, pyrimidine, and pyridine rings as well as the position of the hydrogen atoms at the heteroatoms. Compounds labelled with ¹⁵N and ¹³C atoms were used to check the assignments made.For Communication 3, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 116–120, January, 1992.     

Condensation of 1-aryl-5-methyltetrazoles with aldehydes

Chemistry of Heterocyclic Compounds -     

Regioselectivity of Nucleophilic Attack on the Reactions of 1,2,4-Triazine 4-Oxides with Certain C-Nucleophiles

The addition of CH-active compounds to 6-aryl-1,2,4-triazine 4-oxide is reversible and occurs under conditions of kinetic control at position 5 of the heterocycle to form cyclic C(5)-^H adducts. Under conditions of thermodynamic control the nucleophilic attack is directed to position 3 of the heterocycle and is accompanied by its opening to form the more stable open chain addition products. Attack of ethylmagnesium bromide is directed exclusively to the 5 position of the 6-aryl-1,2,4-triazine 4-oxides as a result of the irreversibility of the given reaction.     

Nitroazines. 5. Use of the japp-klingemann reaction for the synthesis of nitrotriazines

Condensation of diazoles with -dicarbonyl nitro compounds (nitromalondialdehyde and nitromalondiester) gives derivatives of azolo[5,1-c] [1,2,4]triazine with a nitro group in the triazine ring.For 4, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 662–665, May, 1986.     

Cycloaddition to sym-tetrazines (the carboni-lindsey reaction) (review)

The available data on the reaction of sym-tetrazines with various unsaturated compounds from 1958 to 1980 are systematized. The reaction of sym-tetrazines with alkenes, alkadienes, alkynes, and unsaturated carbocycles and heterocycles are presented.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1462–1478, November, 1981.     

Transformations of 8-substituted tetrazolo[1,5-<Emphasis Type="Italic">a</Emphasis>]pyrazines

The reactions of 8-chlorotetrazolo[1,5-a]pyrazine with N-, O-, and S-nucleophiles involve the ipso substitution of the chlorine atom. Heating of this compound with benzotriazole or phenyltetrazole results in elimination of the nitrogen molecule from one of the tetrazole rings to form new annelated azapentalenes. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 334–338, February, 2007.     

Synthesis and transformations of 3-azido-5-amino-1,2,4-triazines

The reaction of the tetrazolediazonium ion with malonic acid dinitrile and nitroacetonitrile leads to the formation of 3-azido-5-amino-1,2,4-triazine derivatives. According to the mass-spectrometric data and the results of X-ray diffraction analysis, the crystalline compounds exist in the amino form. The facile hydrolysis of the amino and azido groups to azauracils is an argument in favor of the existence of the imino form in solution.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 557–561, April, 1984.     

Effect of electron impact on 9-phenylacridines

The high intensities of the molecular-ion peaks in the mass spectra of 9-phenylacridines, the absence of ions characterizing cleavage of the interannular bond, and the high selectivity of the fragmentation constitute evidence for the presence of conjugation between the aromatic rings of the system. Dehydrogenation processes during electron impact that lead to the formation of condensed systems are peculiar to the investigated compounds. Unique detachment of an amino group from the (M-H)⁺ ion was noted for 9-(4-aminophenyl)acridines.