- One-Step Synthesis of 2-[(2-Carboxyphenyl)amino]-6-formylnicotinic Acid via Photolysis of 2-Azidobenzoic Acid in the Presence of Weak Bases
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Abstract: 2-Azidobenzoic acid has undergone rearrangement into 2-[(2-carboxyphenyl)amino]-6-formylnicotinic acid under irradiation in aqueous-organic media in the presence of acetates of alkali or alkaline earth metals. The structure of the resulting comp
- Budruev, A. V.,Davydov, D. A.,Dzhons, D. Yu.,Giricheva, M. A.,Pokrovskaia, A. V.
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p. 2013 - 2018
(2021/11/13)
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- Synthesis of 2,1-benzisoxazole-3(1H)-ones by base-mediated photochemical N-O bond-forming cyclization of 2-azidobenzoic acids
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The base-mediated photochemical cyclization of 2-azidobenzoic acids with the formation of 2,1-benzisoxazole-3(1H)-ones is reported. The optimization and scope of this cyclization reaction is discussed. It is shown that an essential step of the ring closure of 2-azidobenzoic acids is the formation and photolysis of 2-azidobenzoate anions.
- Dzhons, Daria Yu.,Budruev, Andrei V.
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supporting information
p. 874 - 881
(2016/07/06)
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- Electrosynthesis and in situ chemical rearrangement of o-nitrosobenzamides
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Primary and secondary o-nitrosobenzamides can be prepared in a "redox" cell but are unstable in the solvent used for electrolysis (acetate buffer-alcohol).At room temperature N-aryl-2-nitrosobenzamides give 2-carboxyazobenzenes.N-alkyl-2-nitrosobenzamides decompose thermally into 2-methoxy or 2-ethoxycarbonylphenylhydrazones according to the alcohol used.Similarly, methyl benzoate (or ethyl benzoate) is obtained from 2-nitrosobenzamide.A possible mechanism involves an unstable heterocycle formed by the coupling of the two nitrogen atoms (nitroso and amide) followed by cleavage of the carbonyl-nitrogen bond resulting from nucleophilic attack of the solvent (water or alcohol). Key Words: flow cell electrosynthesis / 2-nitrosobenzamides / 2-carboxyazobenzenes / 2-alkoxycarbonylphenylhydrazones / indazol-3-one
- Guilbaud-Criqui, A.,Moinet, C.
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p. 101 - 110
(2007/10/02)
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- Photochemistry of (2-nitrophenyl)diazomethane studied by the matrix isolation technique. (Nitrophenyl)carbene to (carboxylphenyl)nitrene rearrangement by successive reduction of the nitro group with the carbenic center
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Irradiation (λ > 350 nm) of (2-nitrophenyl)diazomethane (1) matrix-isolated in Ar at 10 K provided 2-nitrosobenzaldehyde (3) presumably as a result of intramolecular oxygen migration in (2-nitrophenyl)carbene (2). Upon further irradiation (λ > 350 nm), 3 was decomposed to give a mixture of 2,1-benzisoxazol-3(1H)-one (4) and carbonylcyclopentadiene imine (5) along with CO2. The oxazolone (4) underwent decarboxylation to give 5 upon irradiation with shorter wavelength light (λ > 300 nm) but not at longer wavelength (λ > 350 nm), suggesting 4 is not the direct precursor for 5 in the photolysis of 3. Irradiation (λ > 350 nm) of (4-n-butyl-2-nitrophenyl)diazomethane (1b) under similar conditions resulted in the formation of carbonyloximinocyclohexadienylidene (7) which then produced the oxazolone (4b) and the imine (5b) upon further irradiation, suggesting that a 1,4-biradical generated as a result of abstraction of H at the ortho position by the photoexcited nitroso group was involved in the reaction of 3 forming 4. (2-Carboxyphenyl)nitrene (9) generated by 1,4-OH shift in the 1,4-biradical was postulated as an intermediate leading to 5, and this was actually demonstrated by independent generation of 9 by the photolysis of 2-azidobenzoic acid (8).
- Tomioka, Hideo,Ichikawa, Naoki,Komatsu, Kazunori
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p. 8045 - 8053
(2007/10/02)
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- Electrochemical reduction of N-(o-nitrobenzoyl) and N-(o-nitrobenzyl)-amides or imides. Electrosynthesis of quinazoline derivatives.
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Controlled potential electrolysis at a mercury pool cathode, carried out at the plateau of the first reduction wave of o-nitrobenzoylacetamide, leads to 4-hydroxy-2-methylquinazoline 1-oxide, resulting from a ring closure of the phenylhydroxylamine intermediate.In the same conditions, o-nitrobenzoylsuccinimide gives rise to a tricyclic compound which undergoes a nucleophilic attack from the electrolysis medium, with formation of 4-hydroxyquinazoline 1-oxide bearing at the position 2, either a propanoate group (acidic media) or a propanamido group (ammoniacal buffer).At last, the hydroxylamino derivative issued from o-nitrobenzoyl- phtalimide reduction, disproportionates in acidic medium and a mixture of 2-(o-carboxyphenyl)-4-hydroxyquinazoline 1-oxide and of the parent quinazoline is obtained at the term of the electrolysis.As a matter of comparison, the parent o-nitrobenzyl substrates have been studied; no ring closure occurs at the hydroxylamino stage but quinazoline derivatives can be obtained from the corresponding anilines by electroreduction at more negative potentials. Key words: polarography / cyclic voltammetry / controlled potential electrolysis / quinazoline 1-oxyde / quinazoline
- Chibani, A.,Hazard, R.,Tallec, A.
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p. 814 - 822
(2007/10/02)
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