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1.
Heterocyclic dienamines III. A re-examination of the reaction of Fischer's base on tetracyanoethylene Depending on the order of addition, Fischer's base 5 (1,3,3-trimethyl-2-methylidene-indoline) reacts 1:1 with tetracyanoethylene to give either the tricyanovinylation product 6 or the spiro compound 7 . A skeletal rearrangement of a zwitterionic intermediate can explain the formation of the spiro compound. The latter undergoes a thermal isomerization yielding by ring expansion the tetrahydroquinoléine 8 . On reaction with LiAlH4 or CH3ONa 7 and 8 lead both to triazatetracycles. All structures are assigned on the basis of spectral data.  相似文献   

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Derivatives of acridine, acridone and xanthone were prepared from (+)-camphor, 3-Arylidene, 3-arylmehtyl or 3-aroylcamphors with an halogen in the ortho position and dibornanonylarylmethanes may be uased aas precursors. Ring closure may be induced by ammonia, armoatic amines or potassium hydroxide with or without a catalyst. Good yaields were obtained. In come casaes, the reaction goes with an aromatisation of the heterocyclic moiety.  相似文献   

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The aroylhydrazones of ethyl benzoate have been prepared in fair yield by the action of aroylhydrazines on ethyl benzimidate hydrochloride. These products give rise, quantitatively, at their melting point, to 5-aryl-2-phenyl-1,3,4-oxadiazoles, and, in the presence of hydrazine hydrate, in boiling 1-propanol to 4-amino-5-aryl-3-phenyl(4H)-1,2,4-triazoles (Yields 50%). The addition of methylmagnesium iodide to these products give aroylhydrazones of acetophenone.  相似文献   

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We have accomplished the intramolecular oxymercuration of γ-δ ethylenic alcohols, with different mercuric salts under different conditions. By “in situ” reduction, or by direct reduction of isolated mercuric compounds, we obtain, in some cases, diastereoisomers with different relative yields.  相似文献   

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Studies of Organometallic Compounds. XVII Synthesis of Tetracyclohexyltitanium Tetracyclohexyltitanium is prepared by reaction of TiCl4 or Ti(OC4H9)4 with dicyclohexylmagnesium in pentane or ether at - 30°. Some aspects of its reactivity and its decomposition are described.  相似文献   

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The condensation of methylated N-heterocycles and espically monomethyl- and polymethylpyridinets on phthalic enhydrides leads to 2-ary1-1,3-indanediones. The 3alklidenylphthalides formed in an intermediary state have been isloated. The influence of solvents and temperature on the velocity and yeild of formation of 2-(2- and 4-pyridyl)-1,3-indandiobnes has been studies. The ir and nmr spectra confirm taht these compunds exist under a β-diketoenamine form resonating witj a betaine form.  相似文献   

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Photochemical synthesis of biaryls and heterobiaryls from aryl and heteroarylamines, alkylnitrite and aromatic or heteromatic substrates The photochemical reaction of aromatic and heteroaromatic amines with excess t-butyl nitrite in aromatic solvents (benzene, p-xylene, mesitylene) and in hetero-aromatic solvents (furan, thiophene) leads to biaryls or heterobiaryls. t-Butyl nitrite is more convenient than isopentyl nitrite which gives by-products. This new method has been used to synthesize 28 compounds in 17 to 60% yield.  相似文献   

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The pKa1 and pKa2 of 19 biheterocycles A-(CH2)-n B(in which A and B represent pyrazole, imidazole, or pyridine rings, and n=0 or 1) were determined in water at 25° using poterntiometry and UV spectroscopy methods.  相似文献   

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Diamines react with 3-dimercaptomethylenecamphor giving either a bis-oxothioamide or a heterocyclic compound via in oxoaminothioamide intermediate. In this last reaction, there is cleavage of both C? S bonds. Similarly, diamines react with β-oxothioamides to produce the same heterocyclic derivatives. In these reactions, a transamination is involved and the carbonyl group of camphor is preserved. A distinctly different reaction occurs when the same camphor derivatives are treated with hydrazine; thioxo- alcoylamino- or arylaminoindazoles are then obtained. Ring closure occurs on the carbonyl carbon of the camphor molecule.  相似文献   

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