Electrochemical generation of a nickel–carbonyl complex, catalyst for the electroreductive coupling of organic halides and carbon monoxide into ketones

The nickel–carbonyl complex Ni(CO)bpy is involved in the nickel-catalysed electroreductive coupling of organic halides and carbon monoxide into ketones. The active species is obtained from a stoichiometric mixture of Ni⁰, 2,2′-bipyridine and CO. The electrochemical method used to generate this complex allows a good tuning of Ni⁰ production versus CO dissolution. We have shown that Ni(CO)bpy results from a CO equilibrium exchange between Ni(CO)₂bpy and Nibpy.