[2,2']bipyridinyl; potassium phosphate; copper diacetate; palladium diacetate in dimethyl sulfoxide T=100°C; 12 h;

acetic acid in ethanol T=80°C; 24 h;

1: 88 percent / gas. hydrogen chloride / CHCl3 / -5 °C 2: 90 percent / hydrogen sulphide / pyridine / 2 h / 0 °C 3: 76 percent / acetic acid / ethanol / 24 h / 80 °C View Scheme

1: neat (no solvent) / 120 °C 2: palladium diacetate; copper diacetate; [2,2']bipyridinyl; potassium phosphate / dimethyl sulfoxide / 12 h / 100 °C View Scheme