Time-resolved flash spectroscopic investigations of the reactions of singlet arylhalocarbenes

The results of time-resolved laser flash spectrometric studies of singlet arylhalocarbenes are reviewed. In particular, the absolute rate constants for reactions of phenylchlorocarbene and related carbenes with alkenes are summarized and systematized. The experiments described provide the basis for a detailed examination of carbenic reactivity-selectivity principles. The results of studies on the influence of temperature on the absolute rate constants for carbene reactions are consistent with the existence of transient carbene/alkene intermediates.     

METHYL SALICYLATE FLUORESCENCE AS A PROBE OF THE GEOMETRY OF COMPLEXATION TO CYCLODEXTRINS

Abstract Methyl salicylate (MS) is found to form complexes with α-, β- and γ-cyclodextrins in aqueous solution. The fluorescence of the complexes differ dramatically from that of MS in pure aqueous solution in the case of α- and γ-cyclodextrin, but is similar to that of MS in pure aqueous solution in the case of β-cyclodextrin. The binding constants for the complexes have been evaluated and the fluorescence of the complexes has been employed to infer the geometry of the complexes.