Hydrazone Anions Research Articles

Salt forms of sulfadiazine with alkali metal and organic cations.

The structures of four salt forms of sulfadiazine (SDH) with alkali metal cations are presented. Three contain the deprotonated SD anion (C10H9N4O2S). These are the discrete complex diaqua{4-[(pyrimidin-2-ylazanidyl-κN1)sulfonyl-κO]aniline}lithium(I), [Li(SD)(H2O)2], (I), and the coordination polymers poly[{μ3-4-[(pyrimidin-2-ylazanidyl)sulfonyl]aniline}sodium(I)], [Na(SD)]n, (II), and poly[diaqua{μ3-4-[(pyrimidin-2-ylazanidyl)sulfonyl]aniline}potassium(I)], [K(SD)(H2O)2]n, (III). Na complex (II) is a three-dimensional coordination polymer, whilst K complex (III) has two crystallographically independent [K(SD)(H2O)2] units per asymmetric unit (Z' = 2) and gives a two-dimensional coordination polymer whose layers propagate parallel to the crystallographic ab plane. The different bonding modes of the SD anion in these three complexes is discussed. Structure (IV) contains protonated SDH2 cations {4-[(pyrimidin-2-yl)sulfamoyl]anilinium, C10H11N4O2S} and the Orange G dianion [OG, 7-oxo-8-(phenylhydrazinylidene)naphthalene-1,3-disulfonate, C16H10N2O7S2], namely, 4-[(pyrimidin-2-yl)sulfamoyl]anilinium tetraaqua[7-oxo-8-(phenylhydrazinylidene)naphthalene-1,3-disulfonato]sodium(I) sesquihydrate, (SDH2)[Na(OG)(H2O)4]·1.5H2O. The [Na(OG)(H2O)4]2 dimers have antiparallel naphthyl ring structures joined through two Na centres that bond to the hydrazone anions through the O atoms of the ketone and sulfonate substituents. The structures of the salts formed on reaction of SDH with 2-aminopyridine and ethanolamine are also presented as 2-aminopyridinium 4-[(pyrimidin-2-ylazanidyl)sulfonyl]aniline, [C5H7N2][SD], (V), and ethanolaminium 4-[(pyrimidin-2-ylazanidyl)sulfonyl]aniline monohydrate, [HOCH2CH2NH3][SD]·H2O, (VI), respectively. Structure (V) features a heterodimeric R22(8) hydrogen-bond motif between the cation and the anion, whilst structure (VI) has a tetrameric core of two cations linked by a central R22(10) hydrogen-bonded motif which supports two anions linked to this core by R33(8) motifs.

ChemInform Abstract: Highly Substituted Pyrazoles and Pyridazines by MIRC Reactions of Hydrazone Anions and Nitrobutadienic Fragments.

AbstractDifferent approaches are investigated to the pharmaceutically interesting heterocyclic systems.

Highly-substituted pyrazoles and pyridazines by MIRC reactions of hydrazone anions and nitrobutadienic fragments

In prosecution of the synthetic exploitation of nitrobutadienes deriving from the initial ring-opening of nitrothiophenes, their multifaceted behavior finds a further clear-cut example in their Michael-type acceptor reactivity toward the anions of α-oxohydrazones. Thus, depending on the starting diene, new poly-functionalized pyrazoles are obtained. Furthermore, most interestingly, in one occasion a dichotomy has been observed, depending on the nature of the Michael-type donor, leading with complete selectivity to either 5-member or 6-member N-heterocycles. The outcome encompasses motifs for both mechanistic and synthetic interest, for example, in the field of heterocycles endowed with possible pharmacological/biological activity.

Solvatochromic hydrazone anions derived from chalcones

The preparation and solvatochromism of anions derived from the 2,4-dinitrophenylhydrazones of 1,3-diphenylpropenone, 1-phenyl-3-(4-nitrophenyl)propenone and 1-phenyl-3-(2-thienyl)propenone are described and their behaviour was interpreted in terms of theoretical calculations of their internal charge-transfer transitions.

ChemInform Abstract: A Straightforward Synthesis of Some Fused Aza‐Arenes via Nucleophilic Displacement of a Ring Hydrogen Atom in Nitroarenes by Aromatic Hydrazone Anions.

AbstractChemInform 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.

A straightforward synthesis of some fused aza-arenes via nucleophilic displacement of a ring hydrogen atom in nitroarenes by aromatic hydrazone anions

6-Nitroquinoline 6 undergoes direct cyclocondensation with aromatic aldehyde hydrazones 9 in the presence of sodium hydride in DMF at low temperature, giving the corresponding 3-aryl-1H-pyrazolo[3,4-f]quinolines 10 and/or 3-aryl[1,2,4]triazino[6,5-f]quinolines 11 in low to moderate yield. With aromatic keto hydrazones 7, 3,3-disubstituted 2,3-dihydro[1,2,4]triazino[6,5-f]quinoline-4-oxides 8 are obtained in moderate to good yield. The mode of cyclocondensation is considerably dependent on the electronic nature of a ring substituent of the aromatic hydrazones; electron-donating substituents favor the formation of 11, while electron-withdrawing substituents work favorably for the formation of 10. Monocyclic nitroarenes 15 react similarly with 4-nitrobenzaldehyde hydrazone 9a to give another type of cyclocondensation product, 3-aryl-1H-indazoles 16, in moderate yield. In contrast, nucleophilic substitution of a ring hydrogen atom takes place with 4-methylbenzaldehyde hydrazone 9f to yield N-arylated hydrazone 22b, which, however, fails to cyclize to 16 under the conditions employed. The reaction has been suggested to proceed through the initial attack of a hydrazone anion on the position adjacent to the nitro group, followed by migration of an ipso hydrogen atom to the nitro group in the Meisenheimer intermediate 18. The resulting N2-arylated hydrazone anion would undergo ring closure via either addition to the nitroso group or displacement of this moiety, eventually leading to the fused aza-arenes 8, 10/11, 13 or 16.

Electrochemical Formation of Indazoles from Tropone Tosylhydrazones: Electrochemical Oxidations of Sodium Salts of Tosylhydrazones of Tropone and 2-Phenyltropone

Electrochemical oxidations of the sodium salts of tropone and 2-phenyltropone tosylhydrazones afforded 2-tosyl-2H-indazole and 1-tosyl-7-phenyl-1H-indazole, respectively. The reactions proceeded through the cyclizations of the corresponding hydrazyl radicals generated by electrochemical one electron oxidations of the hydrazone anions

ChemInform Abstract: MICHAEL‐TYPE ADDITIONS OF OXIME AND HYDRAZONE ANIONS WITH METHYL α‐BROMOACRYLATE. X‐RAY STRUCTURE DETERMINATION OF A BROMOCYCLOPROPANE DERIVATIVE

AbstractDie Anionen (I) und (IV) reagieren mit dem Bromacrylsäureester (II) zu den Additions‐ Verbindungen (III) bzw. (V).

Michael-type additions of oxime and hydrazone anions with methyl α-bromoacrylate. X-Ray structure determination of a bromocyclopropane derivative

Oxime and hydrazone anions undergo a michael-type addition with methyl α-bromoacrylate leading to bromocyclopropane derivatives, the structure of which has been established by X-ray analysis.

The formation of diazoalkanes from the reaction of hydrazone anions with [formula omitted]-toluenesulfonyl azide

The formation of diazoalkanes from the reaction of hydrazone anions with [formula omitted]-toluenesulfonyl azide

Diazoalkanes from hydrazone anions. Novel oxidation reaction

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDiazoalkanes from hydrazone anions. Novel oxidation reactionWolfgang. Fischer and Jean P. AnselmeCite this: J. Am. Chem. Soc. 1967, 89, 20, 5312–5313Publication Date (Print):September 1, 1967Publication History Published online1 May 2002Published inissue 1 September 1967https://doi.org/10.1021/ja00996a056RIGHTS & PERMISSIONSArticle Views206Altmetric-Citations22LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (266 KB) Get e-Alerts Get e-Alerts