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1.
The condensation of 1,5-diaminoimidazoles with ethyl aceto-acetate gives two types of compounds: imidazo[1,5-b]-1,2,4-triazepinones and imidazo[4,5-b]pyridinones. The structure of these compounds is demonstrated by rmn and mass spectroscopy. The formation of imidazo[4,5-b]pyridinones from imidazo[1,5-b]-triazepinones through a new transposition is also shown.  相似文献   

2.
The reaction of 3,4-diamino-5-oxo-4,5-dihydro-l,2,4-triazine or its 6-methyl or 6-phenyl substituted derivatives and ethyl acetoacetate gave three compounds: 4,7-dioxo-9-methyl-1,4,6,7-tetrahydro-as-triazino[4,3-b]-1,2,4-triazepine in poor yield, isomeric 4,9-dioxo-7-methyl-1,4,8,9-tetrahydro-as -triazino[4,3-b]-1,2,4-triazepine and by competitive cyclisation, 2-methyl-7-oxo-3,7-dihydro-s-triazolo[3,2-c]-1,2,4-triazine. By condensation of 3-methylamino-4-amino-5-oxo-4,5-dihydro-1,2,4-triazine with ethyl acetoacetate, the formation of 4,9-dioxo-7,10-dimethyl-4,8,9,10-tetrahydro-as-triazino[4,3-b]-1,2,4-triazepine was strongly favored.  相似文献   

3.
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   

4.
The reduction-aldylation of quinoxaline, phthalazine and pyrido[2,3-b] pyrazine by potassium borohydride in a carboxylic acid medium is described. Formic, acetic, chloroacetic and propinic acids were used. The diazine ring of the molecule was reduced and alkylated into an N,N1-dialkyltetrahydro compound. With quinoxaline and formic acid, N-formylation may be an important factor. Sodium borodeuteride allows one to prepare an hexadeuterated compound.  相似文献   

5.
The 2-(1-aziridinyl)tetrahydropyrans cannot be obtained by aminolysis of the 2-dialkylaminotetrahydropyrans. These compounds are synthesized by the Hofmann reaction between 2-chlorotetrahydropyrans and ethylenimine. The effect of acetic anhydride on the 2-(1-aziridinyl) and 2-dialkylaminotetrahydropyrans was studied. The 2-dimethylaminotetrahydropyrans were converted into 2-acetoxytetrahydropyrans and dimethylacetamide by cleavage of the carbon-nitrogen bond. Ring opening of the oxygen heterocycle gives the corresponding dialkylacetamides and polymerised products. The 2-(1-aziridinyl)tetrahydropyrans allow the synthesis of the N-(2-tetrahydropyrannyl)-N-(2-acetoxy-ethyl)acetamides. Acetic anhydride ring opens the nitrogen heterocycle.  相似文献   

6.
Preparation of the tetrahydroisoquinolin-4-ols indicated in the title and their oxidation by different reagents (chromic anhydride, NBA, dimethylsulfoxide, Oppenauer oxidation) is reported. Only the last reaction led to the title compounds, while the other reagents (except NBA) yielded 1,2,3-trioxotetrahydroisoquinoline. Furthermore, the reactivity of 6,7-dimethoxytetrahydroisoquinolin-4-one was examined towards different carbonyl reagents.  相似文献   

7.
The condensation of 3,4-diamino 1,2,4-triazole with ethyl aceloacelate gave 6-methyl-8,9-dihydro(7H)-s-triazolo[4,3-b]-1,2,4-triazepin-8-one ( 2 ); 2 has been caracterized by nmr spectroscopy and by comparison with its methylated derivative prepared in an unambigous manner.  相似文献   

8.
The NMR. spectra of a serie of β-hydroxyesters have been studied. It has been found that the methylene protons are magnetically nonequivalent only when the substituents on the center of asymmetry of I or II are very different. The magnetically non-equivalence of the isopropylmethylprotons arise when the β-hydroxyesters contain an aromatic or aromatic conjugated group directly bonded to the asymmetric carbon. The interpretation of this finding is proposed.  相似文献   

9.
1-Amino-2-dimethylamino-ethane and 1-amino-3-dimethylamino-propane react with o-methoxycarbonylphenyl isothiocyanate (I) to yield the corresponding 3-(ω-dimethylaminoalkyl)-2-thiono-1,2,3,4-tetrahydroquinazolin-4-ones (V). The tertiary amino group of V is quaternized to the corresponding ammonio derivative VI when treated with methyl iodide in methanol.  相似文献   

10.
Kinetic studies of the substitution of isomeric N-methyl-halogeno-1,2,4-triazoles with piperidine or the methoxide ion have been carried out. The experimental results show that the 1-mcthyl-5-halogcno isomer is more reactive than the 4-methvl-3-halogeno isomer. Various theoretical treatments of the reaction have been applied. The calculations show that the “frontier charge” and “delocalised bond” models give (he best results.  相似文献   

11.
Bis ehlorosulfonylmethane was condensed with several ortho-phenylendiamines in benzene at low concentration, yielding the corresponding bcnzo[e]-1,3,4,7-dithiadiazepine 2,2,4,4-lrtroxides. A similar heterocycle was obtained from bischlosulfonylmethane and 2-amino-5-chlorobenzhydrylamine. Mass spectrometry results were discussed with reference to one of the series.  相似文献   

12.
A new synthesis of β-hydroxyesters involving a reaction between a carbonyl compound, ketene and an alkyl-orthotitanate is described. The following carbonyl compounds have been studied: aldehydes, ketones, α-diketones, α- or γ-ketoesters. A reaction mechanism is proposed.  相似文献   

13.
In this work we present a new aproch for the synthesis of tri aned tetracyclic heterocycles in the indole series.  相似文献   

14.
Hydrazinoethyl phosphoric monoester has been prepared by reacting hydrazinoethanol with polyphosphoric acid, and isolated as di-sodium salt. Sodium hydrazinoethyl phosphate reacts with phenylisothiocyanate (in H2O+ethanol) to yield mainly the derivative thiocarbamoylated at the substituted nitrogen atom. This derivative, heated for one night at 100° in 0.5 N HCl, is cyclized to 3-amino-2-phenylimino-thiazolidine in 62% yield. Sodium hydrazinoethyl phosphate reacts with o-methoxycarbonylphenyl isothiocyanate (in H2O+dioxane) at the unsubstituted nitrogen atom to yield mainly the corresponding quinazoline derivative (IV, X = OPO3Na2). This derivative, heated for one night at 100° in 0.5 N HCl, is cyclized to 2-o-carboxyphenylamino-dihydro-δ2-1, 3, 4-thiadiazine (Va) in 55% yield (hydrolysis of the lactamic function as well). Aminoethyl phosphorous monoester (colaminephosphorous acid) reacted with phenylisocyanate (in H20+dioxane) in slightly alkaline medium (one equivalent of NaOH) yields sodium N-phenylcarbamoylaminoethyl phosphite. Refluxed for 20 minutes in 1N NaOH, this carbamoyl derivative is not cyclized but only hydrolyzed to the open-chained N-phenyl-N′-hydroxyethylurea (VII).  相似文献   

15.
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   

16.
Tetrabenzyltitanium, tetraphenyltitanium, and tetramethyltitanium were studied by using NMR. spectroscopy. The spectrum of tetrabenzyltitanium depends on the procedure of its preparation. An interpretation of this finding is proposed.  相似文献   

17.
The action of organolithium reagents such as phenyllithium or n-bulyllithium on 2-methylquinoxaline gave lithiation of the methyl group which upon reaction with electtropholesphiles produce side chain alkenyl derivatives. On the other hand organolithium reagents react with the quinoxaline azomethine bond to give I-lithio-2-alkyl)or ary-1)-3 methylquinoxalines which can be further loithiated on the methyl group to give 2-alkyl(or aryl)-3-alkenylquinoxaline derivatives. The adducts can be condensed with clectrophiles such as benzonitrile or methlyl benzoate but only methyl benzoate leads to N condensed derivatives. Furthermore substituted 1,2,3,4-terahydroqinoxalines are available via the above lithio intermediates.  相似文献   

18.
Reaction with Tetracyanoethylene of Enamines derived from Cyclohexanone At room temperature enamines of cyclohexanone react with tetracyanoethylene (TCNE) to give substituted tetrahydroindenes 5 . The structures are assigned on the basis of 13C-NMR. data and confirmed by hydrolysis. Spectroscopic studies (IR., UV., ESR.) at different temperatures indicate that the reaction can follow two routes: classical zwitterion formation, or a concurrent electron transfer between the enamines and TCNE leading to the derivates 5 . These are the first reported examples of the γ-carbon reactivity of an enamine.  相似文献   

19.
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   

20.
Low temperature 1H NMR was unsuccessful in conformational analysis of substituted benzophenones. However, induced lanthanide chemical shifts study permitted us to check satisfactorily the results obtained by Rayleigh depolarised light scattering and dipole moment studies on meta and ortho substituted benzophenones. The existence in solution, of a conformational equilibrium in these cases is confirmed.  相似文献   

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