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Simonov, Yurii A.; Fonarı, Marina S.; Lipkowski, Janusz; Yavolovskii, A. A.; Ganin, E. V.

doi:10.1023/a:1025612912040

Cited by 16 publications

(15 citation statements)

References 10 publications

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“…Compound (2) was synthesized according to [14] by the reaction of 6-amino-5-nitrosouracil with phenylhydrazine hydrochloride in the presence of sodium acetate. The yield was 89%; mp 250°C.…”

Section: Methodsmentioning

confidence: 99%

Liquid-phase oxidation of dibenzyl ether by atmospheric oxygen in the presence of homo- and heteroligand pivalate and 3,5-dimethylpyrazolate complexes of 3d metals

et al. 2009

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The main products of the reaction in the presence of homo-and heteroligand pivalate and 3,5-dimethylpyrazolate mono-, bi-, and trinuclear complexes of Co, Cu, Ni, and Zn are the hydroperoxide, benzaldehyde, and benzoic acid. The effect of the composition and structure of the complexes on the conversion of the substrate, the selectivity of the process, and the possibility of alternative routes to the oxidation of dibenzyl ether is discussed.Metal carboxylates are some of the best known and most widespread classes of coordination compounds, the variety of which is due to the broad possibilities of the structural function of the polydentate ligand RCOO - [1]. It is this specific characteristic that makes it possible to vary the composition and structure of carboxylate complexes, leading on the one hand to the unusual characteristics (catalytic, magnetic, etc.) of such compounds (e.g., see [2,3]) and on the other to the possibility of using them as "platforms" for the production of the metal complexes regarded as synthetic analogs of the active part of metalloenzymes [4][5][6].Thus, the authors of [7-11] developed approaches to the synthesis of a similar series of pivalate complexes of zinc, copper, nickel, and cobalt containing coordinated 3,5-dimethylpyrazole (Hdmpz), which models the histidine fragment in the enzyme part of metalloenzymes.In a continuation of our investigations into the catalytic properties of the polynuclear carboxylates of 3d metals in the liquid-phase oxidation of compounds with activated CH bonds [e.g., dibenzyl ether (DBE) [12]] by atmospheric oxygen (and then by air) in the present article features of the oxidation of DBE in the presence of complexes (mainly bi-and trinuclear complexes) of cobalt, copper, nickel, and zinc, in which the metal cores are formed by pivalate (ì-Piv) or 3,5-pyrazolate (ì-dmpz) bridging ligands, are discussed. As seen from Table 1, the terminal ligands in these complexes are either neutral 0040-5760/09/4506-0355

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Section: Methodsmentioning

confidence: 99%

Liquid-phase oxidation of dibenzyl ether by atmospheric oxygen in the presence of homo- and heteroligand pivalate and 3,5-dimethylpyrazolate complexes of 3d metals

et al. 2009

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“…As starting compounds we used 5-nitroso derivatives of 1-hydroxyethyl-6-aminouracil (Ia) [3], 4,6-diamino-1,2-dihydropyrimidin-2-one (Ib) [4], and 2,4,6-triaminopyrimidine (Ic) [4], and also 3-nitroso-2,6-diaminopyridine Id [5]. Treatment of Ia3Id with sulfur or selenium monochloride under the conditions similar to those described in [1] resulted in formation of 1,2,5-chalcogenadiazole N-oxides IIa3IIh in good yields (Scheme 1).The reactive functional groups present in the starting amino nitroso compounds, at equimolar ratio of the reactants, exert no appreciable effect on the course of cyclization with the formation of 1,2,5-thiadiazole N-oxides and their selenium analogs.An alternative route to 1,2,5-oxa-, -thia-, and selenadiazoles, based on transformations of aliphatic and aromatic 1,2-dioximes [6 38], is limited by difficult availability of heterocyclic 1,2-dioximes.With 6-amino-5-nitrosouracil Ie as example, we showed that the amino group in an acidic medium is readily replaced by hydroxylamine; the reaction product isomerizes into uracil 5,6-dioxime IIIa existing, according to single crystal X-ray diffraction data, in the form of the (4Z,5E) isomer [9]. The reactions between Ib3Id and excess hydroxylamine taken as a mixture of acetate and hydrochloride resulted in replacement of all the amino groups with the formation of tri-and tetraoxime derivatives of pyrimidine (IIIb, IIIc) and pyridine (IIId) (Scheme 2).…”

mentioning

confidence: 96%

“…With 6-amino-5-nitrosouracil Ie as example, we showed that the amino group in an acidic medium is readily replaced by hydroxylamine; the reaction product isomerizes into uracil 5,6-dioxime IIIa existing, according to single crystal X-ray diffraction data, in the form of the (4Z,5E) isomer [9]. The reactions between Ib3Id and excess hydroxylamine taken as a mixture of acetate and hydrochloride resulted in replacement of all the amino groups with the formation of tri-and tetraoxime derivatives of pyrimidine (IIIb, IIIc) and pyridine (IIId) (Scheme 2).…”

mentioning

confidence: 96%

Synthesis of 1,2,5-Oxa-, -Thia-, and -Selenadiazole N-Oxides from Nitroso- and Isonitrosopyrimidines

et al. 2005

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The possibility of preparing 1,2,5-oxa-, -thia-, and -selenadiazole N-oxides from polyfunctional nitroso-and isonitrosopyrimidines and -pyridine was examined.We found previously that the reactions of 6-amino-5-nitrosouracils with sulfur or selenium monochloride yield 1,2,5-chalcogenadiazolo [3,4-d]pyrimidines [1,2]. In this study we examined the applicability of this reaction to o-amino nitroso compounds containing additional reaction centers such as hydroxy and amino groups. As starting compounds we used 5-nitroso derivatives of 1-hydroxyethyl-6-aminouracil (Ia) [3], 4,6-diamino-1,2-dihydropyrimidin-2-one (Ib) [4], and 2,4,6-triaminopyrimidine (Ic) [4], and also 3-nitroso-2,6-diaminopyridine Id [5]. Treatment of Ia3Id with sulfur or selenium monochloride under the conditions similar to those described in [1] resulted in formation of 1,2,5-chalcogenadiazole N-oxides IIa3IIh in good yields (Scheme 1).The reactive functional groups present in the starting amino nitroso compounds, at equimolar ratio of the reactants, exert no appreciable effect on the course of cyclization with the formation of 1,2,5-thiadiazole N-oxides and their selenium analogs.An alternative route to 1,2,5-oxa-, -thia-, and selenadiazoles, based on transformations of aliphatic and aromatic 1,2-dioximes [6 38], is limited by difficult availability of heterocyclic 1,2-dioximes.With 6-amino-5-nitrosouracil Ie as example, we showed that the amino group in an acidic medium is readily replaced by hydroxylamine; the reaction product isomerizes into uracil 5,6-dioxime IIIa existing, according to single crystal X-ray diffraction data, in the form of the (4Z,5E) isomer [9]. The reactions between Ib3Id and excess hydroxylamine taken as a mixture of acetate and hydrochloride resulted in replacement of all the amino groups with the formation of tri-and tetraoxime derivatives of pyrimidine (IIIb, IIIc) and pyridine (IIId) (Scheme 2). The reactivity is apparently influenced by the steric factors: 1-Substituted 6-amino-5-nitrosouracils do not react with hydroxylamine under the similar conditions. Scheme 1.

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“…As a rule a pair of protons of the substituent takes part in bonding, and the stability of the compounds decreases in the following order: OH > NH 2 > CH 2 [4]. The crystalline supramolecular compounds of crown ethers with heterocycles are stabilized by hydrogen bonds either through one of the above-mentioned substituents in the heterocycle [5][6][7][8][9][10][11][12] or the cyclic ammonium group of the protonated heterocycle [13]. A single example of the formation of a crystalline supramolecular compound of the most effective [3,14] crown ether 1b with unsubstituted triazole is known [15].…”

mentioning

confidence: 99%

“…1302-1305, September, 2006. Original article submitted October 7, 2005. cis-anti-cis-eicosahydrodibenzo[b,k][1,4,7,10,13,16]hexaoxacyclooctadecene;(4) 1H-imidazole-4,5-dicarbonitrile; (5) 3-nitro-1,2,4-triazole; (6) 1H-tetrazole…”

mentioning

confidence: 99%

Reaction of crown ethers with five-membered heterocycles: 1H-imidazole-4,5-dicarbonitrile, 3-nitro-1,2,4-triazole, and 1H-tetrazole

Wang

Tang

Ganin

2006

Chem Heterocycl Compd

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one proton at each of the two proton-donating atoms separated by one covalent bond, it was shown that uncharged crystalline supramolecular compounds can be obtained on account of the proton-donating characteristics of the aromatic heterocycles.An indispensable condition for the formation of crystalline supramolecular compounds [1, 2] of crown ethers with organic molecules is the presence in the latter of proton-donating centers with one of the atoms C, N, or O, particularly H 2 N-, H 2 NSO 2 -, H 2 NCS-, H 2 NHNCO-, H 2 C=, H 3 C-, H 3 CO-, and similar groups or water molecules [1-3], securing stabilization of the components of the supramolecular compound by hydrogen bonds. As a rule a pair of protons of the substituent takes part in bonding, and the stability of the compounds decreases in the following order: OH > NH 2 > CH 2 [4]. The crystalline supramolecular compounds of crown ethers with heterocycles are stabilized by hydrogen bonds either through one of the above-mentioned substituents in the heterocycle [5][6][7][8][9][10][11][12] or the cyclic ammonium group of the protonated heterocycle [13]. A single example of the formation of a crystalline supramolecular compound of the most effective [3,14] crown ether 1b with unsubstituted triazole is known [15].The aim of this work was to determine the possibility of synthesizing uncharged crystalline supramolecular compounds of various crown ethers with five-membered aromatic heterocycles, containing one proton at each of two adjacent proton-donating atoms separated by one covalent bond and securing stabilization of the supramolecular compound by analogy with the data in [15].It was established that the crystalline supramolecular compounds [1b·4]-7, [2·4]-8, [3·2(4)]-9, [1a·5]-10, [1b·2(5)]-11, [2·2(5)]-12, [3·2(5)]-13, and [3·2(6)]-14 respectively are formed during spontaneous evaporation of the solvents from solutions of the crown ethers 1-3 with the respective heterocycles 4-6.

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Untitled

Cited by 16 publications

References 10 publications

Liquid-phase oxidation of dibenzyl ether by atmospheric oxygen in the presence of homo- and heteroligand pivalate and 3,5-dimethylpyrazolate complexes of 3d metals

Liquid-phase oxidation of dibenzyl ether by atmospheric oxygen in the presence of homo- and heteroligand pivalate and 3,5-dimethylpyrazolate complexes of 3d metals

Synthesis of 1,2,5-Oxa-, -Thia-, and -Selenadiazole N-Oxides from Nitroso- and Isonitrosopyrimidines

Reaction of crown ethers with five-membered heterocycles: 1H-imidazole-4,5-dicarbonitrile, 3-nitro-1,2,4-triazole, and 1H-tetrazole

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