Перегляд за Автор "Markovskii, Leonid"

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Electronic and steric structure “Quasi-verdazyls.” I. Phosphaverdazyl and its leuco base
(1984) Nesterenko, A.; Polumbryk, Oleg; Markovskii, Leonid
By the PNDO method in an spd basis, with complete optimization of geometry, the electronic and steric structure has been calculated for different conformers of a model phosphaverdazyl and its leuco base. The results are consistent with the interpretation given previously for the ESR spectra of phosphaverdazyls. Features of electronic structure are judged in terms of their influence on the physicochemical properties and reactivity of phosphatetrazines.
Quantum-chemical investigation of spatial and electronic structure of verdazyl and its derivatives
(1979) Markovskii, Leonid; Polumbryk, Oleg; Nesterenko, A.
The unrestricted HF method in the INDO approximation with optimized geometry was used to describe the electronic structure of the hetero-ring of verdazyl and the derivatives of the latter. The results obtained are in good agreement with the experimental EPR spectra of triphenylverdazyl radical and its dipole moment. These data may be a basis for understanding and predicting the chemical properties and reactivity and its derivatives.
Synthesis of 5-nitro-N,N-diphenylhydrazinopyrimidines and investigation of their free radicals
(1980) Boldyrev, I. V.; Polumbryk, Oleg; Markovskii, Leonid; Cherkasov, V. M.
A number of 5-nitro-N,N-diphenylhydrazinopyrimidines were synthesized. Free radicals were obtaines by oxidation of these compounds with PbO2. The stabilities of 5-nitro-4-pyrimidinylhydrazyl radicals are close to the stability of the α,α-diphenyl--2,4-dinitrophenylhydrazyl radical. The structures of the compounds obtained were confirmed by the UV, IR, PMR and EPR spectra.
Verdazyl radicals with perfluorphenyl rings
(1978) Polumbryk, Oleg; Ryabokon, Ivan; Markovskii, Leonid
New formazans, tetrazines, and verdazyl radicals containing pentafluorphenyl residues were synthesizedon the basis of the reaction of perfluorphenylhydrazones with benzenediazonium salts. The stabilities of the free radicals obtained considerably exceed stability of the diphenylpicrylhydrazyl radical.