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61.
62.
V. A. Roznyatovskii V. V. Roznyatovskii Yu. A. Ustynyuk 《Russian Chemical Bulletin》2004,53(10):2196-2199
The 13C-{1H} and 119Sn-{1H} NMR spectra of hexaethyldistannane were measured and analyzed using an iteration program for the calculation of the complete line shape with correction of a residual inhomogeneity of the magnetic field and phase distortions. Signals of 22 isotopomers containing magnetic isotopes of tin and carbon in different pairwise and triple combinations were identified, and their spectral parameters were determined. The content of isotopes 119Sn, 117Sn, and 115Sn in the molecule was determined with a high accuracy sufficient for the study of isotope effects in chemical reactions.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2102–2104, October, 2004. 相似文献
63.
64.
N. V. Roznyatovskaya G. A. Tsirlina V. V. Roznyatovskii M. D. Reshetova Yu. A. Ustynyuk 《Russian Journal of Electrochemistry》2004,40(9):955-962
The electroreduction of a binuclear complex of copper(II) with a macrocyclic Schiff base of the Robson type on the basis of 4-tert-butyl-2,6-diformylphenol and 1,3-diaminopropane on the dropping-mercury, gold, amalgamated-gold, and glassy-carbon electrodes is studied in an aqueous environment. The data of experiments on preparative electrolysis and the results of measurements by a method of cyclic voltammetry and classic polarography suggest that the complex under study undergoes reduction in an aqueous environment with the transfer of four electrons with formation of copper(0) and a free Schiff base, which in conditions under investigation experiences hydrolytic decomposition. 相似文献
65.
66.
I. V. Borisova N. N. Zemlyanskii A. K. Shestakova V. N. Khrustalev Yu. A. Ustynyuk E. A. Chernyshev 《Russian Chemical Bulletin》2000,49(5):933-941
The [Ph3P+−CMe2−SiMe2−SEt]Br− salt was prepared by the reaction of betaine Ph3P+−CMe2SiMeR−S− (1a: R=Me) with EtBr. Acetylation of betaine1a or Et3P+−CHMeSiMe2−S− (2a) afforded 2,2,6-trimethyl-1,3-dioxa-2-silacyclohex-5-ene-4-thione 相似文献
67.
I. V. Borisova N. N. Zemlyanskii A. K. Shestakova V. N. Khrustalev Yu. A. Ustynyuk e. A. Chernyshev 《Russian Chemical Bulletin》2000,49(9):1583-1592
Photolysis and thermal decomposition of betaines R3P−CR1R2−SiR3R4−S− (1) follows two main pathways: (a) a Corey—Chaykovsky type reaction with elimination of Ph3P and generation of silathiirane
(2) and (b) a retro-Wittig type reaction accompanied by elimination of R3P=CR1R2 and generation of silanethione R3R4Si=S (3). Highly reactive compounds2 and3 undergo subsequent transformations to give derivatives of tetrahydro-1,4-dithia-2,5-disilin, 1,3-dithia-2,4-disilolane, and
phosphonium salts ofsymm-tetraorganodisilthiane dithiolates [Ph3P+CHR1R2]2[(R3R4SiS−)2S]. The structures of the compounds obtained were established by X-ray diffraction analysis and multinuclear NMR spectroscopy.
For part 3, see Ref. 1.
The betaines Et3P+CHMeSiMe2S− and Et3P+CHMeSiPh2S− with alkyl groups at the phosphorus atom are distinguished by high thermal stability; their spectral characteristics do not
change during storage of solutions of these compounds in pyridine-d5 or metastable solutions in benzene-d6 for 1–2 years at −20°C in sealed evacuated tubes or on heating (150°C) for 15 h.
Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1594–1603, September, 2000. 相似文献
68.
N. N. Zemlyansky I. V. Borisova A. K. Shestakova Yu. A. Ustynyuk E. A. Chernyshev 《Russian Chemical Bulletin》1994,43(12):2126-2127
A new method for the generation of organosilanones by the reaction of betaines, R3P+-CR1R2-SiR3R4-S–, with (Et3Sn)2O was suggested.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2246–2247, December, 1994.This study was financially supported by the Russian Foundation for Basic Research, Project No. 94-03-09710. 相似文献
69.
S. V. Kukharenko L. N. Novikova V. V. Strelets N. A. Ustynyuk 《Russian Chemical Bulletin》1994,43(1):41-46
It has been shown by cyclic voltammetry in a THF medium in the temperature range from –70 °C to +20 °C that one-electron electrochemical reduction of (6-C13H10)Cr(CO)3 (1) to the corresponding 19-electron anion radical (1
–) is accompanied by splitting off of a H atom to form the 18-electron carbon-centered anion (6-C13H9)Cr(CO)3 (–2
), which at room temperature undergoes intramolecular haptotropic isomerization to the metal-centered (5-C13H9)Cr(CO)3
– (–
3) anion. The reversible one-electron reduction of3
– to the corresponding 19-electron radical dianion3
2.– induces 5 6 interannular isomerization. In contrast to the equilibrium shift to the 5-isomer in 18-electron complexes 2 and 3, in their 19-electron analogs the equilibrium is shifted to the 6-isomer.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 48–53, January, 1994.This work was carried out with financial support from the Russian Foundation for Basic Research (no. 93-03-5209) 相似文献
70.
A. N. Nesmeyanov E. G. Perevalova L. I. Leont'eva Yu. A. Ustynyuk 《Russian Chemical Bulletin》1966,15(3):528-529
Conclusions Triferrocenylchloromethane hydrochloride reacts with nucleophilic reagents (organomagnesium and-sodium compounds, aluminum lithium hydride, sodium methylate, sodium cyanide) to yield the corresponding triferrocenylmethane derivatives. 相似文献