| Abstract
| - The effect of β-cyclodextrin (β-CD) on the mononuclear heterocyclic rearrangement of the(Z)-phenylhydrazone of 3-benzoyl-5-phenyl-1,2,4-oxadiazole (1) in aqueous borate buffer at pH =9.6 has been analyzed at temperatures ranging from 293.15 to 313.15 K. The trend of the absorptionspectra of 1 as a function of time has been accounted for with the formation of two different 1:1complexes between β-CD and 1, the first, “unreactive” complex being formed faster than the“reactive” one. The occurrence of negative activation enthalpy values for the studied interconversionevidences the kinetic relevance of inclusion processes. Computational models elaborated using theMM2 molecular mechanics force field give an idea of the relative importance of the differentcomplexes, additionally helping us to formulate a suitable reaction scheme.
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