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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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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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Diazomethane reacts with N-(p-nitrophenoxy-carbonyl)-aniline giving on the one hand p-nitroanisole and phenylisocyanate, the latter being transformed into N-phenyl-β-propiolactam, and on the other hand N-(p-nitrophenoxy)-acetanilide by insertion. N-(phenoxy-carbonyl)-aniline does not react. The insertion reaction seems to depend on the heterolysis of the bond between the oxygen of the p-nitrophenoxy group and the carbamic carbonyl function, which is strongly polarized (existence of a mesomeric nitro-phenoxonium). The insertion is equally influenced y the nature of the radical R attached to the carbamic nitrogen: with R = ? CH2COOC2H5 the reaction yields only isocyanate, with R = ? C6H5 it yields at the same time the isocyanate and the insertion product. 相似文献
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The carbonyl-containing compounds react with the amides of phenyl-1-thioglyoxalic acids ( 3 ), and if methyl iodide is present, cause cyclisation into 4-methylthio-5-phenyl-2,5-dihydrooxazol-5-ols ( 4 ). The ketal hydroxyl group of the latter can be methylated. When a hydrogen atom exists in the 2-position (cyclisation with an aldehyde), its elimination provides an oxazole 7 . 相似文献
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Reactions of 5-phenylthieno[3,2-b]pyran-7-one, 2-phenylbenzo[b]-thieno[3,2-b]pyran-4-one and the corresponding thiones with sodium ethylate, guanidines, hydrazines and amines are described and compared to those observed with benzopyranones. 相似文献
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The conformations of N-(1-phenylcyclohexyl)piperidinium chloride and some 4-substituted derivatives in H2O and CDCl3 were studied by means of 13C NMR. The results confirm the greater stability of compounds with equatorial piperidinium. Certain characteristics in the observed chemical shifts may be attributed to deformations of the cyclohexyl system, probably caused by the phenomenon of solvation. 相似文献
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R. Locqueneux 《International journal of quantum chemistry》1972,6(1):1-21
A general formalism is set up to apply the variation-perturbation method to the quantum theory of non-linear optical effects, in particular to the electric and magnetic birefringence (Kerr and Cotton-Mouton effects). The quantities describing these effects are obtained from the wave function Ψ of the ground state of the unperturbed molecule and the different vectors and tensors which are determined by a variation method. With this method an approximate computation of the Kerr and Cotton-Mouton constants of some simple molecules has been made. 相似文献