Crystal structure and photolysis spin-trapping EPR investigations of aqua(2-methoxycarbonylethyl)cobaloxime and its β-cyclodextrin inclusion complex †

Abstract

Aqua(2-methoxycarbonylethyl)cobaloxime 1 and its β-cyclodextrin inclusion complex 2 were synthesized and characterized by ¹H NMR and X-ray crystallography. Structural and conformational comparisons between the inclusion complex and the guest compound are made. The rearrangement reaction of the methoxycarbonylethyl radical was observed in the anaerobic photolysis of aqua(2-methoxycarbonylethyl)cobaloxime in the absence and presence of β-cyclodextrin by using the EPR spin-trapping technique. The changes of EPR parameters indicate that the formed spin adduct could be included in the β-cyclodextrin’s cavity.

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