Generation and properties of episulfonium intermediates communication 5. Stereochemistry of formation and opening of episulfonium complexes obtained from cis- and trans-butenes

Conclusions It was shown that stable intermediates of the type of episulfonium ions can be generated by the reaction of the cis- and trans-butenes with the 2,4-dinitrophenylsulfene and p-chlorophenylsulfene hexafluoroantimonates. The stereochemistry of the formation and opening of these intermediates was established, and also the conditions of their cis-trans interconversions.See [1] for Communication 4.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2743–2749, December, 1976.     

Measurements on arc discharges. In nitrogen at 1 atm and higher pressure

Summary After preliminary experiments in different gases the arc between carbon electrodes in nitrogen is investigated more closely. The axial electric field strength between homogeneous carbon electrodes (mainly at 3–6 A and 1–4 atm) and also in arcs with KCl in the anode (at 4 A and 1–5 atm) proves to be a linear function of the pressure. The field strength is higher than in air and is reduced by the KCl. The sum of cathode- and anode-fall is found to be independent of the pressure. The central temperature in the arc without KCl was hard to measure, because self-absorption influenced the intensity ratios of the molecular bands in the spectrum. With KCl this difficulty did not appear, and temperatures were measured of about 7000°K, slightly increasing with the nitrogen pressure. Because the carbon electrodes evaporate much more slowly than in air, the arc in nitrogen is less stationary than in air; this hindered the measurements.     

Coexistence of superconductivity and magnetism

A model consisting of the B.C.S.-Hamiltonian and Zener's s-d exchange interaction is solved rigorously in the thermodynamic limit. Coexistence of superconductivity and magnetism is only possible for an impurity spin concentration smaller than a half at T ≠ 0.     

Investigation of the luminescence spectrum of UO2MoO4

By time-resolved spectroscopy the intrinsic emission spectrum of UO₂MoO₄ at 4.2 K is obtained. The main progressions in the vibronic structure are identified as couplings with the A_g correlation field components of the symmetric and asymmetric UO₂ stretching modes. The intrinsic zero-phonon line in the emission and excitation spectrum is shown to be split both by the crystal field and correlation field. The steady-state emission spectrum at 4.2 K is dominated by emission from traps. The vibronic structure of the trap emission reveals that all traps are distorted uranyl groups.     

Acylation of stereoisometric 2-butenes with cationoid complexes

Conclusions Acylation of the 2-butene isomers with acyl salts can lead either to the formation of , -unsaturated ketones or of conjugate addition products.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1803–1806, August, 1976.     

New possibilities for the use of methoxyallene in carbon-carbon bond-forming reactions

Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 198–199, January, 1988.