NMR spectra of arylaziridines

The ¹³C and ¹H NMR spectra of 1-arylaziridines, 2-phenyl-1-arylaziridines, and 2-aryl-1-phenylaziridines were studied. The additive contributions of aziridinyl, 1-phenyl-2-aziridinyl, and 2-phenyl-1-aziridinyl substituents to the shielding of the aromatic protons were calculated. It is shown that with respect to its donor capacity the aziridine ring occupies an intermediate position between amines and amides. The temperature dependences of the PMR spectra of 1-aryl-substituted aziridines were investigated, and the barriers to inversion of the latter were calculated. The dependence of G on the ^– constants was correlated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 338–341, March, 1978.     

Calculation of boltzmann equation collision integral and accurate solution of relaxation problem

A method of solving the Boltzmann equation on the basis of expansion in Maxwell distributions (Maxwellians) is developed. The calculation of the collision integral consists of two stages: calculation of a two-Maxwellian collision integral and its subsequent expansion in Maxwellians. A special numerical procedure is proposed for approximating functions of one and two variables by a finite number of exponentials; the mean-square deviation of the accurate and approximate functions is minimized and certain moments of these functions are brought into agreement. For a solid-sphere model, the two-Maxwellian collision integral comprises a set of 24 functions over the whole range of the parameters investigated. The Euler method is used to examine the equalization of velocities and temperatures in the gas (quasishock) and resonance recharging of ions on atoms. The accuracy of the solutions obtained is estimated.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 132–141, September–October, 1977.     

Reactions of 2,2-dimethyl-3-phenylazirine with hydrazine and its derivatives

The corresponding -amino ketone hydrazones were obtained by reaction of 2,2-dimethyl-3-phenylazirine with hydrazine, N,N-dimethylhydrazine, methylhydrazine, and semicarbazide. It was established that unsymmetrical azines are formed in the reaction of 2-amino-2-methyl-1-phenyl-1-propanone hydrazone with aliphatic and cyclic ketones. The corresponding tetrahydro-1,2,4-triazines were obtained in the case of the analogous reaction with aliphatic and aromatic aldehydes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 342–346, March, 1978.     

Heterocyclic analogs of xanthone

A comparative investigation of the acid-base properties, the polarographic behavior, and the spectral characteristics of oxochromeno- and oxothiochromenopyrazoles, oxodipyrazolopyrans, and their electronic analogs xanthone and thioxanthone, has been performed. The difference in properties is due to the electron-accepting nature of the condensed pyrazole ring.For communication III, see [8].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 990–992, July, 1973.