Versuche zur Darstellung von Endiazeniumsalzen

Lerche, Holger; Fischer, Hans; Severin, Theodor

doi:10.1002/cber.19851180802

Cited by 9 publications

(3 citation statements)

References 16 publications

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“…The 1 H NMR spectrum (CDCl 3 ), δ, ppm: 2.27 s (3H, CH 3 CO), 3.12 s (6H, NMe 2 ), 6.57 s (1H, =CH). The spectrum coincides with the spectrum of this compound given in [23]. The 1 H NMR spectrum (CD 3 CN), δ, ppm: 2.16 s (3H, CH 3 CO), 3.07 s (6H, NMe 2 ), 6.51 s (1H, =CH).…”

Section: Methodsmentioning

confidence: 85%

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Methylglyoxal bis-(N,N-dimethylhydrazone): Synthesis and some reactions

et al. 2012

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Methods were proposed for the synthesis of the methylglyoxal 1,2-bis-(N,N-dimethylhydrazone). A possibility was shown for the first time of its participation in the Diels-Alder reaction with maleic anhydride as an electron-rich diene. The second reaction of these reagents, which is observed in a wet media, is the formation of the hydrazinium salt of the initial diene with maleic acid. The most probable structure of the protonated diene among the four possible forms was revealed by the quantum-chemical calculations of the energy of the molecules and by the analysis of the 13 C NMR chemical shifts.The methylglyoxal bishydrazones, in particular, substituted bisguanylhydrazones and bisthiosemicarbazones, show pronounced biological activity, and some of them are used as drugs [1][2][3][4][5]. Earlier [6] by the reaction of 2-ethoxypropenal with equimolar amount of 1,1-dimethylhydrazine we obtained in a yield of 8% the previously poorly studied methylglyoxal bis-(N,Ndimethylhydrazone) (II) potentially possessing a pharmacological action.The aim of this work was an optimization of the methods for the synthesis of this compound in diverse ways and the study its properties.By the reaction of 50% aqueous solution of methylglyoxal (I) (commercial reagent) with dimethylhydrazine (molar ratio 1:4) the methylglyoxal bis-(N,N-dimethylhydrazone) (II) was produced. Depending on the experimental conditions and the method of binding water, the yield of bishydrazone II before distillation (according to 1 H NMR spectra) was 37-54%. A by-product of the reaction is methylglyoxal mono-N,N-dimethylhydrazone (III). Molar content of this compound in the reaction mixture was 13-22% depending on the experimental conditions. The formation of monohydrazone III is due to the reversible equilibrium in the water medium of the bishydrazone II and the related product of the hydrolysis at the ketone imine group.To eliminate the water medium we performed the synthesis of methylglyoxal from 2-ethoxypropenal in acetonitrile by the method of [7]. In the subsequent reaction of methylglyoxal with dimethylhydrazine MgSO 4 or molecular sieves 4 Å were used for binding the water formed at the condensation.

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Section: Methodsmentioning

confidence: 85%

“…The distillation provided 0.7 g (32.2%) of substance with bp 70-76°C (4 mm Hg), n D 20 1.5248. According to 1 H NMR, the fraction contains isomers of methylglyoxal bis-(N,N-dimethylhydrazone) II in a ratio of 2.35: 1 and 13.15 mol % of methylglyoxal N,N-dimethylhydrazone III described in [23]. (12).…”

Section: Methodsmentioning

confidence: 99%

Methylglyoxal bis-(N,N-dimethylhydrazone): Synthesis and some reactions

et al. 2012

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“…As functionally substituted aldehydes are generally difficult to obtain and store this route however has only relatively limited application for the synthesis of monofunctionally substituted hydrazone [5][6][7][8][9][10][11] Condensing glyoxal 5a and substituted glyoxal 5b,c with substituted hydrazines leads to formation of mono or bis hydrazones 6 or 7 depending on molar ratio and applied reaction …”

Section: Condensation Of Functionalized Aldehydes and Ketones With Hymentioning

confidence: 99%

Chemistry of carbofunctionally substituted hydrazones

Dib¹,

Al‐Awadi²,

Elnagdi³

2008

Arkivoc

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Umsetzungen mit Monohydrazonen von Dicarbonylverbindungen, XI. Von Glyoxal‐mono(dimethylhydrazon) abgeleitete azavinyloge Aminalether und azavinyloge Amidiniumsalze. Ein Reaktionsvergleich

1985

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CH-Acide Verbindungen lassen sich mit Glyoxal-mono(dimethy1hydrazon) (GMD, I), dem N,O-Acetal von GMD 10a sowie (Hydrazonoethy1iden)ammoniumsalzen 8 zu den entsprechenden Hydrazonoethyliden-Derivaten umsetzen. Die einzelnen Reagenzien werden miteinander verglichen.CH-acidic compounds react with gyloxal monodimethylhydrazone (GMD, l), with the N,Oacetal of GMD 10a, and with (hydrazonoethy1idene)ammonium salts 8 to give the respective hydrazonoethylidene derivatives. The reagents are compared. Im Glyoxal-mono(dimethy1hydrazon) (GMD, 1) ist die Aldehydgruppe durch Konjugation mit der Dimethylaminogruppe desaktiviert. Allerdings sollte dieser Effekt nicht so ausgepragt sein wie bei einfachen Siiureamiden, da in der dipolaren Grenzform 2 eine energiereiche N = N-Doppelbindung vorliegt.GMD 1aDt sich rnit methylenaktiven Verbindungen bei Gegenwart von Alkalien kondensieren und zeigt damit ,,normale" Aldehydaktivitat'). Andererseits wird GMD durch starke Alkylierungsmittel, wie Methyltriflat, am Sauerstoff zu einem (Methoxyviny1)diazeniumsalz (3) alkyliert3).Auch Phosgen und Phosphoroxychlorid addieren sich an den Sauerstoff von GMD zu reaktionsfiihigen Komplexen (4), die nach Art einer azavinylogen Vilsmeier-Reaktion, z. B. mit Phenolen und Indol, zu (Arylviny1)diazeniumsalzen (5) umgesetzt werden konnen4). Hier besteht also groDe Ahnlichkeit mit Reaktionen des Dimethylformamids. Durch Umwandlung von Dimethylformamid in Amidacetale und Aminalether konnen einige fur die praparative organische Chemie sehr niitzliche Reagenzien gewonnen werden. Es lag daher nahe zu prufen, ob von GMD abgeleitete Acetale, N,O-Acetale oder N,N-Aminale, die man auch als aza-0 VCH Verlagsgesellschaft mbH, D-

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Versuche zur Darstellung von Endiazeniumsalzen

Cited by 9 publications

References 16 publications

Methylglyoxal bis-(N,N-dimethylhydrazone): Synthesis and some reactions

Methylglyoxal bis-(N,N-dimethylhydrazone): Synthesis and some reactions

Chemistry of carbofunctionally substituted hydrazones

Umsetzungen mit Monohydrazonen von Dicarbonylverbindungen, XI. Von Glyoxal‐mono(dimethylhydrazon) abgeleitete azavinyloge Aminalether und azavinyloge Amidiniumsalze. Ein Reaktionsvergleich

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