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131.
132.
G. L. Rusinov R. I. Ishmetova N. I. Latosh I. N. Ganebnych O. N. Chupakhin V. A. Potemkin 《Russian Chemical Bulletin》2000,49(2):355-362
A number of 1,4-dihydropyridazines and pyridazines were prepared by the Diels-Alder reaction with an inverse electron demand
from cyclic heterodiene systems, 3,6-bis(3,5-dimethyl-4-R-pyrazol-1-yl)-1,2,4,5-tetrazines, and some enamines as well as from
4-vinylpyridine, butyl vinyl ether, phenylacetylene, and acrylamide. The reaction of 3,6-bis(3,5-dimethylpyrazol-1-yl)-1,2,4,5-tetrazine
with styrene afforded 4,5-dihydropyridazine, which was readily oxidized by atmospheric oxygen to form the corresponding pyridazine.
Electron-withdrawing substituents (Br or Cl) in the pyrazole rings accelerate [4+2]-cycloaddition. When heated, 1,4-dihydropyridazines,
which were synthesized from tetrazines and enamines, eliminated amine to give pyridazines. The reactivities of tetrazines
were evaluated by quantum-chemical methods.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 354–360, February, 2000. 相似文献
133.
E. V. Bartashevich P. V. Plekhanov G. L. Rusinov V. A. Potemkin A. V. Belik O. N. Chupakhin 《Russian Chemical Bulletin》1999,48(8):1553-1557
A method was proposed for estimating the possibility of cyclization of adducts of resorcinol with pyrimidines to form oxadiazocines
based on the conformational criterion and analysis of charges on the C(5) atom of the pyrimidine ring and on the H atom of
the hydroxy group of the resulting adducts. A series of new derivatives of 4,5-dihydro-11H-5,11-methanobenzo[g]azolo[1,3,5]oxadiazocines were synthesized.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1573–1577, August, 1999. 相似文献
134.
V. N. Kozhevnikov D. N. Kozhevnikov V. L. Rusinov O. N. Chupakhin 《Chemistry of Heterocyclic Compounds》1999,35(4):470-473
Reaction of 6-aryl-3-dimethylamino-1,2,4-triazine 4-oxides with KCN results in constriction of the heterocycle and formation
of 3-amino-5-aryl-4-nitrosopyrazoles. Several methods including labelled K13C15N are used to demonstrate that the reaction proceeds through the ANRORC mechanism.
Dedicated to Professor Henk van der Plas on his 70th birthday.
For No. 2, see [1].
Urals State Technical University, Ekaterinburg 620002, Russia; e-mail: mike@htf.ustu.ru. Translated from Khimiya Geterotsiklicheskikh
Soedinenii, No. 4, pp. 532–535, April, 1999. 相似文献
135.
136.
Roman A. Irgashev Arseny A. KarmatskyGennady L. Rusinov Valery N. Charushin 《Tetrahedron letters》2014
3-Benzoyl-4-(thien-2-yl)coumarins have been obtained in good yields according to the SNH addition–oxidation protocol, involving the diastereoselective addition of thiophenes at C-4 of 3-benzoylcoumarins under BBr3 catalysis, followed by oxidation of the intermediate 3,4-trans-3-benzoyl-4-(thien-2-yl)-3,4-dihydrocoumarins with DDQ. This two-step procedure can be regarded as nucleophilic substitution of hydrogen (SNH) on the heterocyclic ring of coumarins. 相似文献
137.
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