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ChemInform Abstract: PYRIMIDINE FORMAZANS
Chemischer Informationsdienst, 1976AbstractAus den Pyrimidylhydrazonen (I) und Diazoniumsalzen (II) werden die Pyrimidylformazane (III) hergestellt und spektroskopisch auf die wahrscheinlichsten tautomeren Formen untersucht.
E. S. KARAVAEVA +3 more
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New synthesis of 28- and 30- crown-formazans and Bis formazans
Tetrahedron, 1998Abstract The macrocyclic cyano crown formazans 3a-c and cyano crown formazans with two formazyl moieties 4a-c were prepared by the azo coupling of the appropriate bis diazonium salts 2a-c with cyanoacetic acid in different medium. The Bis macrocyclic crown formazan 9 was prepared by condensation of 1.3-diaminopropane with the 16-oxo crown formazan 8.
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Die Methylierung 1.5‐ungleich substituierter Formazane
Chemische Berichte, 1969AbstractDie Methylierung des 1‐Phenyl‐5‐p‐tolyl‐formazans (1) führt zu zwei isomeren N‐Methylderivaten (2 und 3). 3‐Methyl‐1‐phenyl‐5‐[4‐nitro‐phenyl]‐formazan (4) bzw. 1.3‐Diphenyl‐5‐diphenylcarbamoyl‐formazan (7) ergeben unter gleichen Bedingungen nur ein N‐Methylderivat (5 bzw. 8).
Neugebauer, F., Jenne, M.
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Trimetallic Iridium–Nickel–Iridium Bis(formazanate) Assemblies
Inorganic Chemistry, 2022Formazans have attracted a lot of attention in coordination chemistry since the early 1940s because of their unique properties engendered by the nitrogen-rich conjugated backbone. Although many studies have been done using formazanates to chelate transition metals, research using formazanates as building blocks for polynuclear compounds and ...
Chenggang Jiang, Thomas S. Teets
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Tetrahedron, 1997
Abstract The 1-aza-2-azoniaallene salts 3 react with 3-cyanoformazans 4–6 to give the corresponding 5-(1,5-diarylformazan-3-yl)triazolium salts 7–9 or the rearrangement derivatives 10–12 or the oxidation products 13–15. Reaction of 3a,d with the crown cyanoformazan 18 gave the corresponding crown-formazanyltriazolium salts 19a,d.
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Abstract The 1-aza-2-azoniaallene salts 3 react with 3-cyanoformazans 4–6 to give the corresponding 5-(1,5-diarylformazan-3-yl)triazolium salts 7–9 or the rearrangement derivatives 10–12 or the oxidation products 13–15. Reaction of 3a,d with the crown cyanoformazan 18 gave the corresponding crown-formazanyltriazolium salts 19a,d.
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Formazans of the pyrimidine series
Chemistry of Heterocyclic Compounds, 1975A series of 1-(2′-pyrimidyl)-3,5-diarylformazans was synthesized. Their structures were studied by means of IR and electronic spectroscopy, and assumptions regarding the most probable tautomeric forms of the investigated compounds were made. The ionization constants of the formazans were measured.
E. S. Karavaeva +3 more
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Tetrazolium salts and formazans
2020Tetrazolium salts discussed here are of the 2-H type, and contain one or more five-membered heterocyclic rings, each of which carries a delocalized positive charge. Such a tetrazolium compound may be represented by a pair of Kekule forms. Tetrazolium salts can be reduced to formazans by a variety of mild reductants, including those of enzyme-catalyzed ...
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ChemInform Abstract: Oxidation of Formazans
ChemInform, 1998AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
R. SHARMA, M. DEVGAN, K. C. KALIA
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The Formazan Reaction in Carbohydrate Research
1958Publisher Summary This chapter discusses the formazan reaction in carbohydrate research. A significant new method for preparing formazans is that of Ried and Hoffschmidt, which makes the heterocyclic formazans easily accessible by way of substituted esters of pyruvic acid.
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Über Formazane und Tetrazene II
Chemische Berichte, 1956AbstractBenzaldehyd‐phenylhydrazone und Benzoldiazoniumsalze reagieren je nach dem ph des Reaktionsmediums unter Bildung von Formazanen, Tetrazenen oder Benzaldehyd‐[p‐benzolazo‐phenylhydrazonen]. Die Tetrazene werden mit alkoholischer Salzsäure in die Kupplungskomponenten gespalten.
Heinrich Hauptmann +1 more
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