ISSN:
1573-1111
Keywords:
Norbornadiene
;
β-cyclodextrin
;
inclusion complex
;
photoisomerization
;
fluorescence
;
absorption spectrophotometry
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract The valence photoisomerization of four aromatic norbornadiene (NBD)derivatives has been studied in ethanol and in 0.01 M β-cyclodextrin(β-CD) water–ethanol (v/v, 99/1) solution (WECD). Observedfirst-order rate constants are found to be of the same order of magnitude inethanol and WECD, ranging between 0.1 and 0.28 s-1, accordingto the compound. These photoisomerization kinetic properties are attributedto the formation of inclusion complexes between NBDs and β-CD. Thestoichiometry is 1 : 1, and association constants ranging between 310 and390 M-1 have been determined fluorimetrically, usingBenesi–Hildebrand plots and a nonlinear regression method. Thestructure of the inclusion complexes is discussed on the basis of AMIsemiempirical dimension calculations and photophysical properties.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1007908709056
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