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V. I. Minkin I. E. Mikhailov G. A. Dushenko O. E. Kompan A. Zschunke 《Russian Chemical Bulletin》1998,47(5):884-894
The kinetics and mechanism of circumambulatory rearrangements of N-centered (NCS) and S-centered (SPh, SC3Ph3, SC(OEt)=S) groups in corresponding derivatives of 1,2,3-triphenylcyclopropene and cycloheptatriene were studied by dynamic1H and13C NMR spectroscopy. Migrations of the isothiocyanate group occur by the dissociation-recombination mechanism with intermediate formation of a tight ionic pair. Migrations of the phenylthio group around the perimeter of cyclopropene and cycloheptatriene rings occur by the 1,2-shift mechanism. It was found that rearrangements of theO-ethyl dithiocarbonate group inS-(1,2,3-triphenylcyclopropen-3-yl)-O-ethyl dithiocarbonate occur by the 3,3-sigmatropic shift mechanism. The molecular and crystal structure ofO-ethylS-(1,2,3-triphenylcyclopropen-3-yl) dithiocarbonate was studied by X-ray analysis. 相似文献
3.
Quantum chemical study of intramolecular rearrangements in 3-allyl-3-methyl-1,2-diphenylcyclopropene
Dushenko G. A. Mikhailov I. E. Mikhailova O. I. Minyaev R. M. Minkin V. I. 《Russian Chemical Bulletin》2021,70(4):699-705
Russian Chemical Bulletin - 3-Allyl-3-methyl-1,2-diphenylcyclopropene (1) and 3-allyl-2-methyl-1,3-diphenylcyclopropene (2) were shown by the DFT B3LYP/6-311++G(d,p) method to interconvert with the... 相似文献
4.
Doklady Physics - The mechanical properties of NWA 12370 chondrite, petrological type H5, depending on the external hydrostatic pressure were studied using ultrasonic waves. This meteorite is a... 相似文献
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Rearrangements of cyclopentadienyl cyanates,isocyanates and their thio-,seleno-, and telluro-analogs
Dushenko G. A. Mikhailova O. I. Mikhailov I. E. Minyaev R. M. Minkin V. I. 《Russian Chemical Bulletin》2009,58(8):1713-1723
Dynamic NMR spectroscopy revealed that pentaphenylcyclopentadienyl isoselenocyanate undergoes reversible hetero-Cope rearrangement
(ΔG
≠
408 K ∼ 22 kcal mol−1, C6D5CD3) giving isomeric selenocyanate in which 1,5-sigmatropic shifts of the SeCN group along the perimeter of the cyclopentadiene
ring occur (ΔG
≠
298 K = 16.7 kcal mol−1, C6D5CD3). On the contrary, pentaphenylcyclopentadienyl iso(thio)cyanates Ph5C5NCO and Ph5C5NCS are structurally rigid compounds on the NMR time scale. The energy barrier to the 3,3-shift of the isoselenocyanate group
in pentaphenylcyclopentadienyl derivative Ph5C5NCSe (ΔG
298 K
≠ = 17.9 kcal mol−1) caclulated using the B3LYP/6-31G** method is 7.6 kcal mol−1 lower than for the unsubstituted analog H5C5NCSe. 相似文献
6.
G. A. Dushenko I. E. Mikhailov O. I. Mikhailova R. M. Minyaev V. I. Minkin 《Russian Chemical Bulletin》2012,61(9):1681-1688
In terms of the density functional theory using the B3LYP functional, 1,2,3,4,5,6,7-heptaphenylcycloheptatriene was shown to be the most stable in the boat conformation of the cycloheptatriene ring with the H atom in the equatorial position. 1,5-Sigmatropic shifts of the H atom along the seven-membered ring perimeter take place when it is in the axial position through the asymmetric transition state with the barrier ΔE ≠ ZPE = 28.7 kcal mol?1. The H atom can attain the axial position upon inversion of the seven-membered ring, which is accompanied by the orthogonal turn of the phenyl group at the sp3-hybridized C atom (ΔE ≠ ZPE = 22.6 kcal mol?1). The energy barrier to the circular rearrangement of the H atom (ΔE ≠ ZPE = 32.2 kcal mol?1) explains formation of isomers during the high-temperature synthesis of di(p-tolyl)pentaphenylcycloheptatriene. The barrier to the 1,5-sigmatropic shifts of the phenyl group is 19.7 kcal mol?1 higher than that for the competing shifts of the H atom. 相似文献
7.
Mikhailov I. E. Artyushkina Yu. M. Dushenko G. A. Minkin V. I. 《Russian Journal of General Chemistry》2020,90(11):2059-2063
Russian Journal of General Chemistry - 2-Aryl-5-butyl-1,3,4-oxadiazoles have been obtained in 59–85% yield via refluxing of equimolar amounts of a benzoic acid hydrazide with trimethyl... 相似文献
8.
Mikhailov I. E. Vikrishchuk N. I. Popov L. D. Beldovskaya A. D. Dushenko G. A. Revinskii Yu. V. Kurbatov S. V. 《Russian Journal of General Chemistry》2017,87(3):575-578
The interaction of 2,3-dimethyl-4-oxo-1,3-benzoxazinium and 2-[β-(4-bromophenylvinyl)]-3-methyl-4-oxo-1,3-benzoxazinium perchlorates with hydrazine hydrate has afforded the corresponding triazoles that have been used as ligands for the synthesis of zinc complexes L2Zn. Luminescent properties of the prepared complexes have been studied.
相似文献9.
10.
I. A. Profatilova A. A. Bumber I. E. Mikhailov G. A. Dushenko M. P. Bubnov V. K. Cherkasov 《Russian Journal of Electrochemistry》2008,44(7):812-817
Redox reactions of a series of substituted cycloheptatrienes are studied on a platinum electrode in acetonitrile using the cyclic voltammetry method. It was found that heptaphenyl-substituted cycloheptatrienes are irreversibly oxidized in two stages in the range of high anodic potentials to form unstable radical cations and dications. As opposed to the unsubstituted and monosubstituted cycloheptatrienes, they are not reduced at the potentials higher than ?2 V (SCE). A new stable radical anion was found in the reduction of N-cycloheptatrienylphthalimide. Its spin density distribution is studied by ESR spectroscopy. 相似文献