1: 89 percent / 45percent hydrobromic acid / 0.33 h / Heating 2: 87 percent / HCl (g) / 23 h / Heating 3: 67 percent / NaOH / methanol; H2O / 0.08 h / Heating 4: 1. 1,1'-carbonyldiimidazole; 2. NH4OH / 1. DMF, 15 min.; 2. DMF, H2O, r.t., 1 h View Scheme

hydrogenchloride 2 h; Heating;

1: 85 percent / dimethylformamide / 5 h / 100 °C 2: 87 percent / KOH / ethanol; H2O / 2 h / Heating 3: 73 percent / HCl (g) / 2 h / Heating View Scheme

1: 87 percent / KOH / ethanol; H2O / 2 h / Heating 2: 73 percent / HCl (g) / 2 h / Heating View Scheme

1: 87 percent / HCl (g) / 23 h / Heating 2: 67 percent / NaOH / methanol; H2O / 0.08 h / Heating 3: 1. 1,1'-carbonyldiimidazole; 2. NH4OH / 1. DMF, 15 min.; 2. DMF, H2O, r.t., 1 h View Scheme