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Claudette Bois Michle Philoche-Levisalles Mansour Chihaoui 《Journal of heterocyclic chemistry》1983,20(1):97-99
The crystal structure or 3-methyl-4-phenylamino-5-phenyl-1,2,4-triazole has been determined by X-ray diffraction. It allows one to choose between the two reaction mechanisms which can be taken into account for the reaction of hydrazine upon N-acylated hydrezonates. 相似文献
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An example of stereospecific and stereoselective reactions is described concerning the cycloaddition of benzonitrile oxyde with 1,2-dimethyl-5-diphenyl-3-pyrazoline. The structure of the two epimeric 5,6-dimethyl 3,4-dimethyl[4,3-d]pyrazolidinoisoxazo-lines-2 was proved by the means of chemical and physical methods. The conversion of one epimeric product to another more stable is achieved and discussed. 相似文献
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Colette Deschamps-Vallet Jean-Baptiste Ilots Michle Meyer-Dayan Darius Molho 《Journal of heterocyclic chemistry》1982,19(1):97-101
3-Phenyl-1-benzopyrylium percholorates 1a, 1i react exculusively at C-2 with ethanol and isopropyl alcohol, affording mixed acetals 2a, 3a, 3i . Aqueous ammonia gives symmetrical secondary amines 4a, 4b or bis(3-phenyl-2H-1-benzopyran-2-yl)amines, while with aqueous aliphatic amines (40%) bis-acetals 5a, 5b or 2,2′-oxy-bis(3-phenyl-2H-1-benzopyrans) are characterized. In some other acidic conditions, 5a and 5b are also obtained. 相似文献
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The condensation of 2-thienylmagnesium bromide with (Z)-1,2-dichloroethene 2,4-dichloropyrimidne, 3,6-dichloropyridazine and with a transition metal catalyst is described. The yields of these reactions are very good; 1,2-bis(2-thienyl)ethene and two new heterocyclic compounds 2,4-bis92-thientyl)pyrimidine and 3,6-bis(2-thienyl)pyridazine were obtained in one step from commercial products. 相似文献
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The N-(p-nitrophenoxy-carbonyl) and N-(phenylthio-carbonyl) derivatives of α-amino-acyl-hydrazides cyclize in presence of diazomethane, yielding hexahydro-1, 2, 4-triazines with simultaneous formation of p-nitro-anisole or thio-anisole respectively. The molecules with a phenoxycarbonyl function such as N-(phenoxycarbonyl)-glycyl-(N, N′-diphenylhydrazide) give the corresponding ring products and anisole only in solvents with high dielectric constant (e.g. nitromethane). The phenylthio-carbonyl derivatives give the same ring products in presence of lead acetate by the intervention of HO?. The p-nitrophenoxycarbonyl derivatives give rise to the same cyclisations in the presence of pyridine by the intermediate of carbamyle-pyridinium ion acting as electrophile. These different types of intramolecular reactions are illustrated by the formation of 1, 2-diphenyl-5-alcoyl-3, 6-dioxo-1, 2, 4-hexahydro-triazines. 相似文献
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The structure of cis 4,5-dihydroxy-3,4-diphenyl-5-methyl-2-isoxazoline has been determined from the X ray crystallographic analysis. The results show the non-planarity of the isoxazoline ring and the presence of intra- and intermolecular hydrogen bonding. 相似文献
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