Estimating gas temperature in the channel of a high-temperature jet discharge in air

Consideration is made of determining gas temperature in the channel of a high-frequency jet discharge in air over the intensity distribution of lines for the rotational spectrum band for the transition A² X²II (0-0) in the radiation of hydroxyl. It is shown that the branches R₂ and Q₁ of this band are the most useful for temperature measurements at atmospheric pressure. Within error limits, the temperature in the discharge channel as determined from the lines of the R₂-branch is T_gas = (3120 ± 70) and (3380 ± 90) K in the cross sections of the discharge at a distance of 3 and 30 mm, respectively.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 3–7, February, 1987.     

Pyrimidines

2-Diazoacetyl-4, 6-diphenylpyrimidine is prepared from 2-chloro-4, 6-diphenylpyrimidine via the nitrile and the corresponding acid, and it is readily converted to 2-bromoacetyl and 2-chloroacetyl-4, 6-diphenylpyrimidine. It was not possible to bring about the Wolff reaction.For Part IV see [12].     

Effect of intramolecular hydrogen bond on the azide-tetrazole equilibrium of 5-(2′-hydroxyphenyl)tetrazolo[1,5-a]pyrimidine,-tetrazolo[1,5-c]pyrimidme, -tetrazolo[1,5-c]quinazoline,and 7-(2′-hydroxyphenyl)tetrazolo[1,5-c]pyrimidine

The intramolecular hydrogen bond between the phenolic hydroxyl and the pyrimidine nitrogen atom in the title compounds exerts a destabilizing effect on the tetrazole ring and shifts the azide-tetrazole equilibrium toward the azide form, especially in the case of tetrazolo[c]pyrimidine and -[c]quinazoline. It has been found that the introduction of a methoxy group into theortho-position of the phenyl fragment stabilizes the tetrazole tautomer more efficiently than introduction of this group into thepara-position.For preliminary communication, see Ref. l.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1494–1502, August, 1995.This work was carried out with financial support from Russian Foundation for Basic Research (Project No. 94-03-0836 la).     

Supramolecular structure of 6-phenyl-2-chloropyrimidine-4-carboxamide and its complexes with dioxane and ethanol

A stable 2:1 complex of 6-phenyl-2-chloropyrimidine-4-carboxamide with dioxane has been synthesized. The structure of the complex was investigated by molecular spectroscopy (chloroform solution), thermoderivatography, and XRD (crystalline phase). A supramolecular structure is formed in the crystal of the complex, which involves centrosymmetric dimer associates of amide molecules, linked by dioxane molecules and intermolecular hydrogen bonds into infinite stepwise ribbons. These ribbons are stacked via π-stacking pair interactions “amidopyrimidine-amidopyrimidine.” The complex of the same 2:1 carboxamido derivative of pyrimidine with ethanol is unstable and has a different structure. The ethanol molecules lie in the vacant voids of the stacks formed by the “amidopyrimidine-amidopyrimidine” synthon.     

Cu(II) and Cu(I) complexes with 2-(3,5-diphenyl-1H-pyrazole-1-yl)-4,6-diphenylpyrimidine: Synthesis and structure. Catalytic activity of Cu(II) compounds in reaction of ethylene polymerization

The Cu(II) and Cu(I) complexes with 2-(3,5-diphenyl-1H-pyrazole-1-yl)-4,6-diphenylpyrimidine (L) of the composition CuLX₂ (X = Cl, Br) and CuL(MeCN)Br are synthesized. According to X-ray diffraction data, the complexes have molecular structures. The molecules L are coordinated to the copper atom in bidentate-cyclic mode, i.e., through the N² atom of pyrazole and N¹ atom of pyrimidine rings. The coordination polyhedron of the Cu²⁺ ion in CuLX₂ compounds is completed to a distorted tetrahedron with halide ions, that of the Cu⁺ ion in CuL(MeCN)Br compounds, with the bromide ion and the nitrogen atom of acetonitrile molecule. The CuLX₂ complexes (X = Cl, Br) in combination with cocatalysts (methylaluminoxane and triisobutylaluminium) exhibit catalytic activity in ethylene polymerization.