Reactivity studies of aryl cobaloximes with molecular oxygen and electrophiles

The reactivity of aryl cobaloximes, ArCo(dmgH)2Py [Ar = Phenyl, 1-naphthyl, 2-naphthyl, 4-NMe2C6H4, 2-thienyl] with molecular oxygen and electrophiles (Br2 and 2,4-dinitrobenzenesulfenyl chloride) has been investigated. All these complexes do not show any affinity toward molecular oxygen and the reaction with electrophiles either leads to ring substitution and/or the Co–C bond cleavage. The molecular structures of two new aryl cobaloximes and two ring substituted organometallic products have been determined crystallographically. The C–H⋯O intermolecular hydrogen bonding interactions in the crystal packing lead to different superstructural motifs.

Aryl cobaloximes do not react with molecular oxygen under thermal or photochemical conditions; however, the reaction with the electrophiles leads to either cleavage of Co–C bond and/or the ring substituted organometallic product. The X-ray structure and crystal packing exhibit some weak interactions to form different types of supramolecular structural motifs.Figure optionsDownload as PowerPoint slideHighlights
► Reactivity studies of aryl cobaloximes with molecular oxygen and electrophiles.
► Electrophiles lead to either Co–C bond cleavage and/or aryl ring substitution.
► X-ray structures of aryl cobaloximes and ring-substituted organometallic products.
► Intermolecular hydrogen bonding interactions lead to different structural motifs.