n-butyllithium; cerium(III) chloride in tetrahydrofuran T=-78 - 20°C; 3 h;

[Ni(2,2'-bipyridine)3(2+)][BF4(1-)]2; tetrabutylammomium bromide; zinc dibromide in N,N-dimethyl-formamide Ambient temperatureelectrolysis (carbon fiber cathode, zinc rod anode);