1: 98 percent / conc. H2SO4, SOCl2 / 72 h / Heating 2: 92 percent / Sodium acetate, Bromine / acetic acid / 0.25 h / Heating View Scheme

1: 98 percent / conc. H2SO4, SOCl2 / 72 h / Heating 2: 83 percent / POCl3 / 0.5 h / Heating 3: 99 percent / Sodium azide / dimethylformamide / 18 h / Ambient temperature 4: 97 percent / H2 / 5percent Pd/C / ethanol / 10 h / 1520 Torr / Ambient temperature View Scheme

1: 67 percent / pyridine / 44 h / 85 °C 2: Ac2O / pyridine / Ambient temperature View Scheme

1: 98 percent / conc. H2SO4, SOCl2 / 72 h / Heating 2: 83 percent / POCl3 / 0.5 h / Heating View Scheme