INVESTIGATION OF THE REDUCTIVE COUPLING OF ARYL HALIDES AND OR ETHYLCHLOROACETATE ELECTROCATALYZED BY THE PRECURSOR NIX(2)(BPY) WITH X(-)=CL-, BR- OR MESO(3)(-) AND BPY-EQUALS-2,2'-DIPYRIDYL/

The mechanism of the coupling of aryl halides and/or ethylchloroacetat e electrocatalyzed by the complex Ni(bpy) in DMF solutions has been re examined using cyclic voltammetry, chronocoulometry and exhaustive ele ctrolysis. The oxidative addition of aryl halides to Ni(bpy) yields tw o arylnickel(II) complexes which were characterized by the splitting o f the reduction wave of the ArNiX(bpy) group. The second oxidative add ition of aryl halides to the ArNi(bpy) complex involves an electron tr ansfer. Biaryl results from a reductive elimination on the diarylnicke l(III) complex. Metathesis of arylnickel(II) or direct reaction betwee n ArNiX(bpy) and ethylchloroacetate may also occur. Values of some kin etic constants have been obtained and a discussion of the whole system is presented.