The Bromination and the Mercuration of Bis(dimethylglyoximato)(styryl)pyridinecobalts(III), Styryl-type Cobaloximes

Abstract cis and trans-p-Cyanostyryl(pyridine) cobaloximes (I and II) and cis and trans-p-methoxystyryl(pyridine)cobaloximes (V and VI) were prepared by the reaction of the reduced form of cobaloxime, bis(dimethylglyoximato)(pyridine) cobalt(I), with cis and trans-p-cyanostyryl bromides and with cis and trans-p-methoxystyryl bromides, respectively. The styryl-type cobaloximes thus obtained retained the stereochemistry, cis or trans, of the starting bromides. The bromination of these styryl-type cobaloximes (I, II, V, and VI) and of the cis and trans-styryl(pyridine)cobaloximes (III and IV) in polar or non-polar solvents gave styryl-type bromides with the retention of configuration. The mercuration of these cobaloximes with mercury(II) acetate in DMF gave styryl-type mercurials, again retaining the original configuration.