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1.
2-Methoxymethyl naphthalene ( 1 ) was synthesized and its properties were found to be different from those reported in the literature. The reaction of this compound with cold conc. nitric acid gave 8-nitro-2-naphthaldehyde ( 2 ). When 1-methoxymethyl naphthalene ( 4 ) was treated similarly 4-nitro-1-methoxymethyl naphthalene ( 5 ) and 8-nitro-1-naphthaldehyde ( 6 ) were obtained.  相似文献   

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1-(5-Nitro-2-thiazolyl)-2-imidazolidinone is synthesized from 2-amino-5-nitro-thiazole and 2-chloroethyl-isocyanate. The structure of this new potent schistosomicide is established by acid and alkaline degradation as well as by synthesis starting from 2-imidazolidinone. A number of derivatives of 1-(5-nitro-2-thiazolyl)-2-imidazolidinone are reported.  相似文献   

4.
Zusammenfassung Für stereochemische Untersuchungen wurden mehrere 1- und 2-substituierte 9,10-Dihydro-9,10-äthano-anthracene (wie die Carbonsäuren, Acetyl-, Formyl- und Methyl-derivate sowie-buttersäuren) dargestellt. DieFriedel-Crafts-Acylierung von1 führt überwiegend zur Substitution in Stellung 2, die isomeren 1-Substitutionsprodukte sind durch Umsetzung geeigneter Anthracenderivate mit Äthylen (und entsprechende Folgereaktionen) zugänglich. Cyclisierung der Buttersäuren9 lieferte die isomeren -Oxo-hexahydro-äthanobenzoanthracene.Die NMR-Spektren der beschriebenen Berbindungen werden kurz diskutiert; zur Erkennung des Substitutionstyps sind die Resonanzen der Brückenkopf-Protenen (an C-9 und C-10) besonders geeignet.
Preparation and proton magnetic resonance spectra of 1- and 2-substituted 9.10-dihydro-9.10-ethanoanthracenes
For stereochemical investigations several 1- and 2-monosubstituted 9.10-dihydro-9.10-ethanoanthracenes (such as the carboxylic acids, acetyl, formyl and methyl derivatives as well as butyric acids) were prepared.Friedel-Crafts acylation of1 leads to substitution predominantly in position 2; the isomeric 1-substitution products are accessible by reaction of suitable anthracene derivatives with ethylene (and subsequent transformations). Cyclizations of the butyric acids9 yield the isomeric -oxo-hexahydro-ethanobenzoanthracenes.The n.m.r. spectra of the compounds described are briefly discussed; for the identification of the type of substitution the resonances of the bridgehead protons (at C-9 and C-10) are especially suitable.
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Irradiation of 1-alkyl-substituted 1,2-dihydronaphthalenes ( 10, 11, 12 ) with a lowpressure mercury lamp yields by ring opening ω-vinyl-o-quinodimethanes, which undergo [1, 7] H-shifts to give 1,2-divinyl-benzenes ( 8, 18, 23 ; cf. schemes 2, 3 and 4). In a further photoreaction of the divinylbenzenes, benzobicyclo [3.1.0]hex-2-enes ( 17, 19, 22 ) are formed. 2-Alkyl-substituted 1,2-dihydronaphthalenes ( 13, 14, 15, 16 ) are transformed by irradiation into ω-vinyl-o-quinodimethanes, which show [1, 7] H-shifts to yield in this case 2-(buta-1′, 3′-dienyl)-toluenes ( 9, 25, 26, 27 ; cf. schemes 6 and 7). The irradiation of 1-methyl- ( 10 ) and 1-ethyl-1, 2-dihydronaphthalene ( 11 ) with a high-pressure mercury lamp produces, besides the products of irradiation using the lowpressure lamp, 2-ethyl-allenylbenzene ( 24 ), and (from 11 ) 4-exo-ethyl-benzobicyclo[3.1.0]hex-2-ene (exo- 20 ) and 2-propyl-allenylbenzene ( 21 ), respectively (cf. scheme 5). Obviously, these products arise from a photreaction of the primarily formed ω-vinyl-o-quinodimethanes a .  相似文献   

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The irradiations of 1, 1-dimethyl- (8), 1, 1-di-(tri-deuteriomethyl)- (d6– 8 ), 1, 1, 2, 2-tetramethyl- ( 9 ) and cis- and trans-1, 2-dimethyl-1, 2-dihydronaphthalenes (cis- and trans- 10 ) were investigated in 2, 2-dimethylbutane/pentane at ?100° using a mercury high-pressure lamp, and with mercury high- and low-pressure lamps at room temperature. The results were compared with one another, and those of the individual compounds are collected in schemes 2 and 4–7. The most important results are the following: 1. The 1, 2-dihydronaphthalenes undergo a conrotatory ring opening to the o-quinodimethanes on irradiation with high- or low-pressure lamps at room temperature or at ?100°. Thermal reactions ([1, 7a]H-shifts, electrocyclisations) are suppressed at ?100°. The o-quinodimethanes formed from 8 (scheme 2), 9 (scheme 5) or cis- 10 (scheme 6) undergo on irradiation with the high-pressure lamp, [1, 5]H-shifts or photochemical Diels-Alder reactions after renewed photochemical excitation, to yield the benzobicyclo[3.1.0]hex-2-ene derivatives. These Diels-Alder reactions do not proceed stereospecifically, and therefore are not orbital symmetry controlled reactions. 2. If the 1, 2-dihydronaphthalenes are irradiated at room temperature with either a high- or a low-pressure lamp, then the initially formed o-quinodimethanes undergo thermal [1, 7a]H-shifts, in preference to all other reactions, as long as this is sterically possible; the resulting products can undergo secondary photochemical transformations. Such o-quinodimethanes are formed on irradiation of 8, 9 and cis- 10 . From trans- 10 , an o-quinodimethane mixture is formed, of which one component (cis, cis- 22 ) undergoes thermal [1, 7a] H-shifts, while the other (trans, trans- 22 ) suffers a thermal disrotatory electrocyclisation to give cis- 10 . If a high-pressure lamp is used in the last experiment, then the competing photochemical Diels-Alder cyclisation to bicyclic compounds of the type 23 (scheme 7) can result in the trans, trans- 22 . As was shown by Salisbury [3], and confirmed by ourselves in other cases [2], photochemical Diels-Alder reactions or [1, 5]H-shifts in the o-quinodimethanes require light of wavelength ? 400 nm (high-pressure lamp). The present photochemical investigations amplify and confirm our earlier conclusions concerning the photochemistry of the 1, 2-dihydronaphthalenes [2].  相似文献   

10.
Zusammenfassung Racematspaltung der 9,10-Dihydro-9,10-äthanoanthracen-1-und 2-carbonsäuren bzw.-(-oxobuttersäuren) (2 a, 2 b bzw.8 a, 8 b) und geeignete Folgereaktionen machten optisch aktive monosubstituierte Derivate von 9,10-Dihydro-9,10-äthanoanthracen,1 (wie die Acetyl-, Formyl- und Methylderivate) sowie aus den buttersäuren9 (erhalten aus8) auch cyclische Ketone (10 und11) zugänglich. Die konfigurative Korrelation der beiden Reihen (a undb) gelang über die Schlüsselsubstanz (+)-1,2,3,4,7,12-Hexahydro-7,12-äthanobenzo[a]-anthracen (12), woraus sich auch die optische Reinheit aller Folgeprodukte ergab.Die absolute Konfiguration wurde durch kinetische Racematspaltung sowohl der Carbonsäure2 a als auch eines mit2 a (und2 b) korrelierten Carbinols14 (nachHoreau) für alle beschriebenen Derivate von1 als (+)-(9R) ermittelt.Neben den []D-Werten wurden auch dieCD-Spektren einiger Derivate von1 gemessen. Diese chiroptischen Daten werden kurz diskutiert.
Optically active 1- and 2-substituted 9.10-dihydro-9.10-ethanoanthracenes; Preparation, chiroptical properties, configurational correlations and absolute configurations
Optically active monosubstituted derivatives of 9.10-dihydro-9.10-ethanoanthracene (1)—such as the acetyl, formyl and methyl derivatives—were prepared by optical resolutions of the carboxylic acids2 a and2 b and the -oxobutyric acids8 a and8 b, resp., and suitable subsequent reactions, whilst from the butyric acids9 (accessible from8) also cyclic ketones (10 and11) were obtained. The configurative correlation of both series (a andb) was achievedvia the key substance (+)-1.2.3.4.7.12-hexahydro-7.12-ethanobenzo[a]anthracene (12) wherefrom also the optical purities of all compounds were deduced.The absolute configurations of all described derivatives of1 were established as being (+)-(9R) by kinetic resolutions both of the carboxylic acid2 a and of a carbinol14 (correlated with2 a and2 b) according toHoreau's method.Besides the []D-values also theCD-spectra of some typical derivatives of1 were recorded. These chiroptical properties are briefly discussed.


Mit 1 Abbildung  相似文献   

11.
Preparation and Characterization of Chromium of Chromium(V)- and Manganese(V)- nitridophthalocyanines(1-) and -(2-): [MNPc(1-)]+ and [MNPc(2-)] (M=Cr, Mn) Nitridophthalocyaninatochromium(V), [CrNPc(2-)], is prepared by oxidation of [Cr(OH)2PC(2-)] with chlorine in the presence of excess ammonia as a paramagnetic (μeff = 1,99 B.M.), Microcrystalline blue powder. Through chemically very stable it reacts as well as the isostructural nitridophthalocyaninatomanganese(V) with bromine or concentrated nitric acid giving ring- oxidized darkblue nitridophthalocyaninatomental(poly)bromides or -nitrates, [MNPc(1-)]X (M=Cr, Mn; X=Bry, NO3; y≈?2). The nitrido-metal stretching vibration (ν(N?M)) is independent of the oxidation state of the Pc-ligands at ca. 1017 cm?1 for the chromium and at ca. 1055 cm?1 for the manganesenitridophthalocyanines. ν(N?Mn) is resonance Raman (r.r.) enhanced, ν(N?Cr) not. The characteristic differences in the u.v. -vis., f.i.r./m.i.r. and r.r. spectra of [MNPc(2-)] and [MNPc(1-)+ and the influence of aggregation of phthalocyanine-radicals are discussed.  相似文献   

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Preparation and Characterization of Cationic η2-1-Butene and Acetonitrile Complexes The reaction of the species η5-C5H5M(CO)n-σ-C4H7 (M = Fe, Mo, W; n = 2, 3) with (C6H5)3CBF4 yielded – instead of the expected cationic butadiene complexes of the type [η5-CpM(CO)n?14-C4H6][BF4], which would have been formed in case of hydride cleavage – compounds of the type [η5-CpM(CO)n η2-C4H8][BF4], which were formed by protonation of the σ-C4H7 ligands. The reaction proceeded quantitatively. The BF4? anion can be substituted by other anions, such as ClO4?, B(C6H5)4?, PF4?, and [Cr(SCN)4(NH3)2]? in the complexes obtained. The mechanism of the reaction leading to the η2-bonded 1-butene complexes was determined by isotope experiments. In trying to recrystallize the butene complexes from acetonitrile the cationic complexes [η5-C5H5 Fe(CO)2CH3CN]BF4 and [η5-C5H5 M(CO)3CH3CN]BF4 were observed; the X-ray structure analysis of the former is reported.  相似文献   

16.
Zusammenfassung Es werden die Veresterungsgeschwindigkeiten der Monoaminobenzoesäuren und der 1- und 2-Pyridinkarbonsäuren bei 25° mit Chlorwasserstoff als Katalysator sowohl in wasserfreiem als auch in wasserhaltigem Glykol und in wasserfreiem Glyzerin gemessen, die derm- und derp-Aminobenzoesäure und der 2-Pyridinkarbonsäure (Nikotinsäure) auch in wasserhaltigem Glyzerin. Die Abhängigkeit der monomolekularen Geschwindigkeitskonstanten vom Wassergehalt (w) des Mediums und dem Überschuß der Konzentration der Salzsäure über die der organischen Säure, bzw. ihres Esters (C) wird für die drei zuletzt genannten Säuren durch Formeln dargestellt. Diese Geschwindigkeitskonstanten nehmen durchwegs sowohl in wasserfreiem als auch in wasserhaltigem Glykol und Glyzerin nicht nur rascher als die Konzentration der gesamten Salzsäure, sondern auch als die des obigen Überschusses, d. h. der freien Salzsäure, zu.FürC=1/3 sind beiw=0.03 die Geschwindigkeitskonstanten derm- und derp-Aminobenzoesäure und der Nikotinsäure in Äthylalkohol um 20–30 %, die der Anthranilsäure um 70%, die der Pikolinsäure um 130% größer als in Glykol, beiw=0.7 dagegen die der drei ersteren Säuren um 35–50% kleiner.In Glykol sind die Konstanten bei der Anthranilsäure und den Pyridinkarbonsäuren kleiner als in Glyzerin, bei den übrigen wie bei den früher untersuchten Säuren aber größer.Die sterische Wirkung der Aminogruppe in Orthostellung ist in Glykol größer, in Glyzerin kleiner als in Äthylalkohol.Unter gleichen Bedingungen Bind die Konstanten der Veresterungsgeschwindigkeit der Nikotinsäure in Glykol und Glyzerin etwa viermal, in Äthylalkohol nur etwa zweimal größer als die der Pikolinsäure.  相似文献   

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The reactions of the monosubstituted guanidines2 b-h with methyl acrylate in dimethylformamide or ethanol as solvent preferentially afford 1-substituted 2-amino-5,6-dihydro-4(1H)-pyrimidinones6 b-h. The structures of 1-hexyl- and 1-benzyl-4-pyrimidinones6 c, e and of the picrate of 1-phenylpyrimidinone6 g were proved by comparison with authentic samples, which were prepared from N-substituted ethyl 3-amino-propionates14 c, e andg and cyanamide. Accordingly,6 g is not identical with authentic 2-phenylaminopyrimidinone7 g (prepared from 2-methylthio-4-pyrimidinone10 and 2-thioxo-4-pyrimidinone12 respectively, compare10).N,N-Disubstituted guanidines2 i-m react with methyl acrylate in dimethylformamide as solvent to afford N2,N2-disubstituted 2-amino-5,6-dihydro-4-(1H)-pyrimidinones7 i-m. Action of morpholine-4-carboxamidine (21) on methyl acrylate in ethanol yields 2-morpholinopyrimidinone71 as byproduct and 3-ethoxy-N-[morpholino(amino)methylene]propionamide (91) as mainproduct.
Herrn Prof. Dr.Robert Ott mit den besten Wünschen zum 60. Geburtstag gewidmet.  相似文献   

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