An efficient and mild procedure for the preparation of aldonic acids via oxidation of D-sucrose by employing N-bromophthalimide oxidant and micellar system / Y. Katre in TENSIDE, SURFACTANTS, DETERGENTS, Vol. 48, N° 1/2010 (01-02/2011)

[article]  inTENSIDE, SURFACTANTS, DETERGENTS > Vol. 48, N° 1/2010 (01-02/2011) . - p. 73-81 Titre : An efficient and mild procedure for the preparation of aldonic acids via oxidation of D-sucrose by employing N-bromophthalimide oxidant and micellar system Type de document : texte imprimé Auteurs : Y. Katre, Auteur ; M. Singh, Auteur ; A. K. Singh, Auteur Année de publication : 2011 Article en page(s) : p. 73-81 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Catalyse Cinétique chimique Concentration micellaire critique Micelles Saccharose Index. décimale : 668.1 Agents tensioactifs : savons, détergents Résumé : The oxidation reactions of D-sucrose have been carried out with N-bromophthalimide in the presence of micellar aggregates at 45°C. The kinetics revealed first order dependence on N-bromophthalimide (NBP) and fractional order dependence on D-sucrose. Variation of mercuric acetate concentration has an insignificant effect on reaction rate. The stoichiometric ratio of NBP:D-sucrose was 1:2 and the oxidation product was aldonic acid confirmed by FeCl3–HCl test. The influence of salts on the reaction rate has also been studied. Phthalimide (NHP) and sulfuric acid (H2SO4) inhibit the rate. Thermodynamic and activation parameters have been evaluated and a mechanism consistent with the kinetic data has been proposed. Cetyltrimethylammonium bromide (CTAB) and TritonX-100 (TX-100) catalyze the reaction, while sodium dodecyl sulfate (SDS) inhibits the rate of reaction. The applicability of Berezin's model was tested to explain the observed micellar effects. The rate constants (kM) and binding constants (KS + KO) have been evaluated. Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=10677 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
012778	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Effect of micellar aggregates on the kinetics of dextrose oxidation by N-bromosuccinimide / Y. Katre in TENSIDE, SURFACTANTS, DETERGENTS, Vol. 47, N° 2/2010 (03-04/2010)

[article]  inTENSIDE, SURFACTANTS, DETERGENTS > Vol. 47, N° 2/2010 (03-04/2010) . - p. 98-105 Titre : Effect of micellar aggregates on the kinetics of dextrose oxidation by N-bromosuccinimide Type de document : texte imprimé Auteurs : Y. Katre, Auteur ; A. K. Singh, Auteur ; M. Singh, Auteur Année de publication : 2010 Article en page(s) : p. 98-105 Note générale : Bibliogr. Langues : Anglais (eng) Tags : Catalyse  micellaire  Oxydation  Cinétique  Concentration  critique  (CMC)  Réactions  bimoléculaires Index. décimale : 668.1 Agents tensioactifs : savons, détergents Résumé : The kinetics of oxidation of dextrose by N-bromosuccinimide (NBS) has been investigated in the presence of cationic cetyltrimethylammonium bromide (CTAB) surfactant in sulfuric acid (H2SO4) medium. Similarly in absence of CTAB solution, the reaction followed fractional, first, and negative fractional-order kinetics with respect to [dextrose], [NBS] and [H2SO4], respectively. Although the reaction mechanism remained unaltered by micelles, a typical kpsi-[CTAB] profile was observed, that is, with a progressive increase in [CTAB], the reaction rate increased, reached a maximum value, and then decreased. The results are treated quantitatively in terms of Berezin's model. Activation parameters were also evaluated and a negative value of deltaS# shows the formation of well-structured activated complex. The influence of salts on the reaction rates has also been seen. On the basis of product analysis, a pertinent mechanism is proposed. Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=8878 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
012052	-	Périodique	Bibliothèque principale	Documentaires	Disponible

---

1 (1 - 2 / 2)