Synthesis of hydrothioxanthenes

Alkylidenedicyclohexanones I–III react with phosphorus pentasulfide in an inert solvent to form sym-octahydrothioxanthenes, which, under the influence of the acid products of the decomposition of phosphorus pentasulfide, are converted to perhydrothioxanthenes and sym-octahydrothioxanthylium salts.See [1] for communication VII.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1196–1199, September, 1972.     

Specific reactions of 5-oxotetrahydro-4H-thiochromenes with Grignard reagents

The reaction of 5-oxotetrahydro-4H-thiochromenes with Grignard reagents has been studied and it has been shown that the reagent adds to the 1,2-position of the conjugated system in the cyclic ketones, The structure of the products depends on that of the starting cyclic ketone.N. G. Chernyshevskii State University, Saratov 410026. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 613–615, May, 1994. Original article submitted April 22, 1994.     

Study of oxidation reactions of 4H-selenopyrans

The oxidation of 4H-4R-2,6-diphenylselenopyrans was studied. This reaction was found to depend on the presence of substituents at C₍₄₎ of the heterocycle and the reaction conditions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 24–26, January, 1995.     

Electromagnetic wave generation in a cylindrical resonator by electrons orbiting in a radial electrostatic field

The mechanisms leading to the generation of microwaves by electrons orbiting in a radial electrostatic field produced by a positively charged filament on the axis of a cylindrical resonator are investigated theoretically. The dispersion relations describing the interaction of the waves with the electrons are obtained. It is shown that the generation of electromagnetic fields is possible on account of both Cherenkov and plasma resonances. The frequencies and growth rates of waves under Cherenkov resonance conditions and also plasma resonance conditions in uniform and nonuniform electron layers are found. The advantages and disadvantages of different generation mechanisms are determined. Zh. Tekh. Fiz. 68, 91–94 (August 1998)     

Pseudo-Jahn-Teller effect in tetragonal local centers

The shape of the light absorption band by a local tetragonal center at the transition _{1 5}(x, y) is investigated in a semiclassical approximation. In addition to interaction with fully-symmetric (₁), Jahn-Teller (₃, ₄) vibrations, inter-action is also taken into account with vibrations ₅, which admix an electron level ₄(z) to the electronic state ₅, which is separated from ₅ by the energetic gap . An analytic computation of the band shape is performed in the first order of the expansion of the form function in ^–1. An asymmetric two-hump band is obtained, where the long-wave maximum always has higher intensity than the shortwave maximum.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 62–67, December, 1987.