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The reaction of tetracyanoethylene with α,β-unsaturated aldehydes under hydrochloric acid catalysis leads to 2,4-dialkyl-7-imino-6-oxabicyclo[3.2.1]oct-3-ene-1,8,8-tricarbonitriles. The structures of these new cyclohexene derivatives were determined by NMR experiments and X-ray crystallography.  相似文献   

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The products of the addition of tetracyanoethylene to ketones react smoothly with aliphatic, aromatic, and heterocyclic aldehydes to give 4,8,8-tricyano-3-imino-2, 6-dioxabicyclo[2.2.2]octanes. The structures of the reaction products were confirmed by 13C, IR, and mass spectral data.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1462–1466, November, 1984.  相似文献   

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New methods have been developed for the synthesis of fused amino-substituted pyrrolidinones and dihydropyrrolones. 4-Oxocyclohexane-1,1,2,2-tetracarbonitriles react with ammonia, hydrazine, and hydroxylamine to give, respectively, 5-amino-, 5-hydrazino-, and 5-hydroxylamino-7-oxo-6-azabicyclo[3.2.1]octane-1,2,2-tricarbonitriles, while with phenylhydrazine, semicarbazide, and thiosemicarbazide, 6-hydrazono-, 6-semicarbazono-, and 6-thiosemicarbazono-3-amino-1-oxo-3a,4,5,6,7,7a-hexahydro-1H-isoindole-3a,7a-dicarbonitriles are formed. The latter can also be obtained under analogous conditions from 5-hydroxy-7-oxo-6-azabicyclo[3.2.1]octane-1,2,2-tricarbonitriles. Reactions of 5-hydroxy-7-oxo-6-azabicyclo[3.2.1]octane-1,2,2-tricarbonitriles with diethylamine or triethylamine give 3-amino-1,6-dioxo-3a,4,5,6,7,7a-hexahydro-1H-isoindole-3a,7a-dicarbonitriles.  相似文献   

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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 692–693, May, 1991.  相似文献   

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The reaction of specifically protected anhydroalditols with (diacetoxyiodo)benzene or iodosylbenzene and iodine is a mild and selective procedure for the synthesis of chiral 6,8-dioxabicyclo[3.2.1]octane and 2,7-dioxabicyclo[2.2.1]heptane ring systems under neutral conditions. This reaction can be considered to be an intramolecular glycosidation that goes through an intramolecular hydrogen abstraction promoted by an alkoxy radical followed by oxidation of the transient C-radical intermediate to an oxycarbenium ion. This methodology is useful not only for the preparation of chiral synthons but also for the selective oxidation of specific carbons of the carbohydrate skeleton, constituting a good procedure for the synthesis of protected uloses.  相似文献   

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Russian Journal of Organic Chemistry - Tetracyanoethylene adducts with ketones, 4-oxoalkane-1,1,2,2-tetracarbonitriles reacted with hydrogen chloride or phosphorus(III) chloride in 1,4-dioxane to...  相似文献   

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The sequential reaction of furfural with cyclic secondary amines and further with benzaldehyde and cyanoacetates affords new 2,4-dicyano-8-(R2N)-6-oxo-3-phenylbicyclo[3.2.1]-octane-2,4-dicarboxylates as rac-(1R,2R,3R,4S,5S,8R)-diastereomers. The structures of the reaction products were determined by X-ray diffraction.

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The 2,6-dioxabicyclo[3.2.1]octane unit, viz 10, present in citreoviridinol (1) has been produced in a stereoselective manner by treatment of the epoxide (8) derived from citreoviral (6), via (7), with p-toluenesulphonic acid.  相似文献   

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Novel 8-substituted bicyclo[3.2.1]octane-6-carboxylic acids have been made via [3+2]cycloaddition to alkyne 2. A number of the corresponding amides are anti-convulsant in mice.  相似文献   

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《Tetrahedron letters》1986,27(5):561-564
In contrast to similar ring system the O-tosyl derivative 2 is rearranged exclusively to the tricyclic aziridine 4. Further tosylation produces the bicyclic tosyl amide 5. The corresponding O-benzoyl-derivatives 6 rearrange in the usual manner with π-assistence to give 7.  相似文献   

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Aromatic aldehydes react with amides of 1-methylindole-2-carboxylic acid under acid catalysis conditions to give 1-aryl-4-methyldihydropyrrolo[3,4-b]indol-3-ones. The intermediate 1-methyl-2-CONHR-3(-X-benzyl)indoles, which are subsequently converted to the indicated cyclic compounds, were isolated. o-Acetyl derivatives were obtained by the action of acetic anhydride on derivatives of unsubstituted amides. Dihydropyrrolo[3,4-b] indol-3-ones were reduced by LiAlH4 to the corresponding dihydropyrrolo[3,4-b] indoles. A mechanism for the formation of dihydropyrrolo[3,4-b] indoles is proposed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1516–1523, November, 1976.  相似文献   

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