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Photophysics and structure of inclusion complex of 4,4-diaminodiphenyl sulfone with cyclodextrin nanocavities / Prosenjit Bhattacharya in Industrial & engineering chemistry research, Vol. 50 N° 13 (Juillet 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 13 (Juillet 2011) . - pp. 7815–7823 Titre : Photophysics and structure of inclusion complex of 4,4-diaminodiphenyl sulfone with cyclodextrin nanocavities Type de document : texte imprimé Auteurs : Prosenjit Bhattacharya, Auteur ; Dibakar Sahoo, Auteur ; Sankar Chakravorti, Auteur Année de publication : 2011 Article en page(s) : pp. 7815–7823 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Physical  Organic  Chemistry Résumé : The structure and dynamics of a charge transfer drug molecule 4,4-diaminodiphenyl sulfone (dapsone) inside the cyclodextrins (α-, β-, γ-CDs) in aqueous solution have been studied using steady state and time-resolved emission spectroscopies. The quantum yields were significantly larger in the presence of β- and γ-CDs than in water, wherein the β-CD confinement shows the largest effect. The results reveal that dapsone forms 1:1 complexes with both β-CD and γ-CD. At higher concentrations of β-CD a combination of 1:1 and 1:2 inclusion complexes could be observed. The average lifetime of the probe inside the CD cavity is larger than that observed in water due to hydrophobic and polarity effects of the nanocage. Anisotropy decay has been used to study the rotational dynamics of the molecule inside the cyclodextrin cavity. 1H NMR data also confirm shallow inclusion of dapsone in β-CD. PM3 semiempirical calculations indicate that for unimolar complex a partial (3.8 Å) encapsulation of the dapsone molecule in β-CD at an angle of 72° with the CD axis. The DFT calculations with solvent effect show that the formation of inclusion is spontaneous and enthalpy driven. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2004797 [article] Photophysics and structure of inclusion complex of 4,4-diaminodiphenyl sulfone with cyclodextrin nanocavities [texte imprimé] / Prosenjit Bhattacharya, Auteur ; Dibakar Sahoo, Auteur ; Sankar Chakravorti, Auteur . - 2011 . - pp. 7815–7823. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 13 (Juillet 2011) . - pp. 7815–7823 Mots-clés : Physical  Organic  Chemistry Résumé : The structure and dynamics of a charge transfer drug molecule 4,4-diaminodiphenyl sulfone (dapsone) inside the cyclodextrins (α-, β-, γ-CDs) in aqueous solution have been studied using steady state and time-resolved emission spectroscopies. The quantum yields were significantly larger in the presence of β- and γ-CDs than in water, wherein the β-CD confinement shows the largest effect. The results reveal that dapsone forms 1:1 complexes with both β-CD and γ-CD. At higher concentrations of β-CD a combination of 1:1 and 1:2 inclusion complexes could be observed. The average lifetime of the probe inside the CD cavity is larger than that observed in water due to hydrophobic and polarity effects of the nanocage. Anisotropy decay has been used to study the rotational dynamics of the molecule inside the cyclodextrin cavity. 1H NMR data also confirm shallow inclusion of dapsone in β-CD. PM3 semiempirical calculations indicate that for unimolar complex a partial (3.8 Å) encapsulation of the dapsone molecule in β-CD at an angle of 72° with the CD axis. The DFT calculations with solvent effect show that the formation of inclusion is spontaneous and enthalpy driven. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie2004797