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Mechanistic study on the oxidation of sulfacetamide by aqueous alkaline diperiodatoargentate(III) / Suresh D. Kulkarni in Industrial & engineering chemistry research, Vol. 48 N°2 (Janvier 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N°2 (Janvier 2009) . - p.591–597 Titre : Mechanistic study on the oxidation of sulfacetamide by aqueous alkaline diperiodatoargentate(III) Type de document : texte imprimé Auteurs : Suresh D. Kulkarni, Auteur ; Praveen N. Naik, Auteur ; Sharanappa T. Nandibewoor, Auteur Année de publication : 2009 Article en page(s) : p.591–597 Note générale : chemical engeneering Langues : Anglais (eng) Mots-clés : Sulfacetamide Résumé : Oxidation of sulfacetamide (SUL), a sulfonamide drug by alkaline diperiodatoargentate(III) (DPA), a powerful oxidizing agent at 298 K and at a constant ionic strength of 0.50 mol/dm3, has been carried out spectrophotometrically at 360 nm. The results indicate that 3 mol of DPA consumed 1 mol of SUL (3:1). The oxidation product has been separated and characterized by IR and NMR spectral studies. The reaction is first order in [DPA] and has less than unit order in [SUL]. The rate constants increased with an increase in alkali concentration and decreased with increase in [IO4−]. Ionic strength and dielectric constant of the medium had negligible effect on the reaction rate. A mechanism has been proposed which explains the observed orders and experimental observations. Monoperiodatoargentate(III) (MPA) has been considered as the active species for the title reaction. The reaction proceeds through a SUL:MPA complex which decomposes in a slow step to give the p-hydroxylamine benzenesulfonamide and Ag(I) species. Further oxidation in the subsequent fast steps yeilds nitroso and nitro derivative of benzenesulfonamide, each transformation consuming 1 mol of MPA. The reaction constants involved in the different steps of the mechanism are calculated. The activation parameters with respect to the slow step of the mechanism are computed and discussed, and thermodynamic quantities are also determined. The probable active species of oxidation have been identified. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8000474 [article] Mechanistic study on the oxidation of sulfacetamide by aqueous alkaline diperiodatoargentate(III) [texte imprimé] / Suresh D. Kulkarni, Auteur ; Praveen N. Naik, Auteur ; Sharanappa T. Nandibewoor, Auteur . - 2009 . - p.591–597. chemical engeneering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N°2 (Janvier 2009) . - p.591–597 Mots-clés : Sulfacetamide Résumé : Oxidation of sulfacetamide (SUL), a sulfonamide drug by alkaline diperiodatoargentate(III) (DPA), a powerful oxidizing agent at 298 K and at a constant ionic strength of 0.50 mol/dm3, has been carried out spectrophotometrically at 360 nm. The results indicate that 3 mol of DPA consumed 1 mol of SUL (3:1). The oxidation product has been separated and characterized by IR and NMR spectral studies. The reaction is first order in [DPA] and has less than unit order in [SUL]. The rate constants increased with an increase in alkali concentration and decreased with increase in [IO4−]. Ionic strength and dielectric constant of the medium had negligible effect on the reaction rate. A mechanism has been proposed which explains the observed orders and experimental observations. Monoperiodatoargentate(III) (MPA) has been considered as the active species for the title reaction. The reaction proceeds through a SUL:MPA complex which decomposes in a slow step to give the p-hydroxylamine benzenesulfonamide and Ag(I) species. Further oxidation in the subsequent fast steps yeilds nitroso and nitro derivative of benzenesulfonamide, each transformation consuming 1 mol of MPA. The reaction constants involved in the different steps of the mechanism are calculated. The activation parameters with respect to the slow step of the mechanism are computed and discussed, and thermodynamic quantities are also determined. The probable active species of oxidation have been identified. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8000474

Oxidation of 6 - aminopenicillanic acid by diperiodatoargantate (III) in aqueous alkaline medium / Shridhar D. Gunagi in Industrial & engineering chemistry research, Vol. 49 N° 20 (Octobre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 20 (Octobre 2010) . - pp. 9666–9672 Titre : Oxidation of 6 - aminopenicillanic acid by diperiodatoargantate (III) in aqueous alkaline medium : A kinetic and mechanistic study Type de document : texte imprimé Auteurs : Shridhar D. Gunagi, Auteur ; Praveen N. Naik, Auteur ; Sharanappa T. Nandibewoor, Auteur Année de publication : 2011 Article en page(s) : pp. 9666–9672 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Oxidation  Kinetic Résumé : Many pharmaceutical compounds and metabolites are being found in surface and ground waters, indicating their ineffective removal by conventional wastewater treatment technologies. Advanced oxidation processes for the transformation of 6-aminopenicillanic acid in water are alternatives to traditional water treatment. Therefore the kinetics of oxidation of 6-aminopenicillanic acid by diperiodatoargentate(III) in alkaline medium at a constant ionic strength of 0.04 mol dm−3 was studied spectrophotometrically at 25 °C. The oxidation products, 2-formyl-5,5-dimethylthiazolidine-4-carboxylic acid and Ag(I), were identified by LC-ESI-MS and IR spectral studies. The reaction between 6-aminopenicillanic acid and diperiodatoargentate(III) in alkaline medium exhibits 1:1 stoichiometry. The reaction shows first order with respect to diperiodatoargentate(III) concentration. The order with respect to 6-aminopenicillanic acid and alkali concentrations is less than unity. The rate goes on decreasing with the increase in the concentration of periodate. Monoperiodatoargentate(III) is considered the active species of the diperiodatoargentate(III). A possible mechanism is proposed. The reaction constants involved in the different steps of the mechanisms are determined. The activation parameters with respect to the slow step of the mechanism are calculated and discussed. The thermodynamic quantities are also determined. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9012562 [article] Oxidation of 6 - aminopenicillanic acid by diperiodatoargantate (III) in aqueous alkaline medium : A kinetic and mechanistic study [texte imprimé] / Shridhar D. Gunagi, Auteur ; Praveen N. Naik, Auteur ; Sharanappa T. Nandibewoor, Auteur . - 2011 . - pp. 9666–9672. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 20 (Octobre 2010) . - pp. 9666–9672 Mots-clés : Oxidation  Kinetic Résumé : Many pharmaceutical compounds and metabolites are being found in surface and ground waters, indicating their ineffective removal by conventional wastewater treatment technologies. Advanced oxidation processes for the transformation of 6-aminopenicillanic acid in water are alternatives to traditional water treatment. Therefore the kinetics of oxidation of 6-aminopenicillanic acid by diperiodatoargentate(III) in alkaline medium at a constant ionic strength of 0.04 mol dm−3 was studied spectrophotometrically at 25 °C. The oxidation products, 2-formyl-5,5-dimethylthiazolidine-4-carboxylic acid and Ag(I), were identified by LC-ESI-MS and IR spectral studies. The reaction between 6-aminopenicillanic acid and diperiodatoargentate(III) in alkaline medium exhibits 1:1 stoichiometry. The reaction shows first order with respect to diperiodatoargentate(III) concentration. The order with respect to 6-aminopenicillanic acid and alkali concentrations is less than unity. The rate goes on decreasing with the increase in the concentration of periodate. Monoperiodatoargentate(III) is considered the active species of the diperiodatoargentate(III). A possible mechanism is proposed. The reaction constants involved in the different steps of the mechanisms are determined. The activation parameters with respect to the slow step of the mechanism are calculated and discussed. The thermodynamic quantities are also determined. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9012562