1: 90 percent / conc. aq. NH3 / various solvent(s) / 2 h / 100 °C 2: 17 percent / (C2H5)4NClO4 / dimethylformamide / 12 h / cathode: Hg, working potential: -1.35 V, charge: 2.6-3.0 F/mol, initial current density: 0.5 A/dm2 View Scheme