1: With thionyl chloride in ethylene glycol dimethyl ether T=50°C; 12 h; 2: With ammonia; water T=50°C; 2 h;

ammonia in tetrahydrofuran; water 0.25 h;

copper(l) iodide; sodium azide; ethanol; caesium carbonate T=20 - 95°C; Inert atmosphereSealed tube;

1: 93 percent / Br2; aq. KOH / 3 h / 60 °C 2: SOCl2 / tetrahydrofuran; dimethylformamide / 20 °C 3: conc. aq. NH3 / tetrahydrofuran; dimethylformamide View Scheme

1: ammonium hydroxide 2: potassium hydroxide; bromine / Heating 3: thionyl chloride View Scheme

1: acetic anhydride 2: ammonium hydroxide 3: potassium hydroxide; bromine / Heating 4: thionyl chloride View Scheme

T=180°C;

1: hydrogen / water; ethanol; ethyl acetate / 1.67 h / 40 °C / 2828.7 Torr / |Cooling; |Large scale 2: hydrogenchloride / ethyl acetate / 30 °C / |Cooling; |Large scale 3: 1-methyl-pyrrolidin-2-one / 30 - 50 °C / |Large scale 4: acetic acid / water / 4 h / |Inert atmosphere; |Reflux; |Large scale View Scheme

hydrogen; palladium on activated charcoal in methanol