Electrochemical Synthesis of the sigma-Aryl Complex [NiBr(Mes)(bpy)] and Its Use as Catalyst Precursor for the Oligomerization of Ethylene (Mes = 2,4,6-Trimethylphenyl, bpy = 2,2 -Bipyridine)

The oxidative addition of mesityl bromide either to electrochemically generated [Ni(bpy)] or to [Ni(COD)2] (COD = 1,5-cyclooctadiene) in the presence of 2,20-bipyridine allows the selective, high-yield synthesis of the r-aryl complex [NiBr(Mes)(bpy)] (Mes = 2,4,6-trimethylphenyl, bpy = 2,20-bipyridine), which is an efficient catalyst precursor for the oligomerization of ethylene to even-numbered olefins in the C4-C26 range with a Schulz-Flory distribution.