Formation of allyl and cyclopropylcarbinyl sulphides in the regiospecific reactions of arenesulphenyl chlorides with allyl- and but-3-enylcobaloximes

Abstract

Allyl- and substituted-allyl-bis(dimethylglyoximato)pyridinecobalt(III) complexes react regiospecifically with 2,4-dinitrobenzenesulphenyl chloride to give moderate (30–45%) yields of the corresponding rearranged allyl 2,4-dinitrophenyl sulphides. The corresponding rearranged allyl derivative of dimethylglyoxime is a major byproduct. But-3-enylbis(dimethylglyoximeto)pyridinecobalt(III) complexes also react regiospecifically to give cyclopropylmethyl 2,4-dinitrophenyl sulphides. The reactions are interpreted in terms of an electrophilic attack of the sulphur on the γ- and δ-carbon of the allyl- or butenyl-ligand, respectively, with concurrent or subsequent loss of cobaloxime(III), and with concurrent or subsequent cyclisation of the organic ligand in the case of the butenyl complexes. Benzenesulphenyl bromide and chloride react much more slowly and their reaction with allylbis(dimethylglyoximato)pyridinecobalt(III) has been briefly explored.