Electroorganic reactions mediated by vitamin B₁₂ model complexes

It is shown that vitamin B₁₂-dependent enzymes; involving the cobalt atoms as a catalytic center, mediate various isomerization reactions accompanied by carbon skeleton rearrangements. The rearrangements were investigated using the hydrophobic vitamin B₁₂ derivatives under electrochemical conditions. As shown, the electrochemical carbon-skeleton rearrangements proceed via formation of anionic intermediates during the electrolysis of alkyl halides with various electron-seeking groups. The data suggest that the migration of a phenyl group on the β-carbon atom results in the formation of a radical intermediate. The enantiomer type is shown to be dependent on the hydrophobic vitamin B₁₂ nature.