Stereochemistry of the reaction of the bis(dimethylglyoximinato)-pyridinecobalt(I) anion with cis- and trans-β-bromostyrenes and with phenylacetylene

Abstract

The bis(dimethylglyoximinato)pyridinecobalt(I) anion reacts with cis- and with trans-β-bromostyrene by direct substitution and with retention of configuration to give the corresponding bis(dimethylglyoximinato)pyridine-cis- and trans-β-styrylcobalt. The possibility that an elimination–addition mechanism of substitution might occur was eliminated by showing that, under the conditions of the substitution, bis(dimethylglyoximinato)pyridine-α-styrylcobalt would be formed from the phenylacetylene intermediate in the elimination–addition mechanism. No α-styryl isomer was detected in the substitution products.