in methanol; water Yield given;

1: 98 percent / dimethylformamide / 20 °C / electrolysis; anode: platinum, cathode: mercury pool; lithium perchlorate, potential of -1V (vs saturated calomel electrode) 2: 81 percent / aq. 15percent HCl, HgCl2 / 6 h / Heating 3: 82 percent / polyphosphoric acid / 1.5 h / 140 °C View Scheme

1: 98 percent / dimethylformamide / 20 °C / electrolysis; anode: platinum, cathode: mercury pool; lithium perchlorate, potential of -1V (vs saturated calomel electrode) 2: 81 percent / aq. 15percent HCl, HgCl2 / 6 h / Heating View Scheme