1: urea / 0.33 h / 150 - 160 °C 2: ethanol / 0.25 h / Heating View Scheme

1: acetic anhydride / 0.08 h / Heating 2: urea / 0.33 h / 150 - 160 °C 3: ethanol / 0.25 h / Heating View Scheme

in ethanol 0.25 h; Heating;

1: pyridine 2: 1.) potassium hydroxide 2.) 72percent hydrazine hydrate / 1.) methanol, reflux, 20 min 2.) methanol, reflux, 30 min 3: 66.5 percent / pyridine 4: 100 percent / ethanol / 2 h / Heating View Scheme

1: pyridine 2: 1.) potassium hydroxide 2.) 72percent hydrazine hydrate / 1.) methanol, reflux, 20 min 2.) methanol, reflux, 30 min 3: 86.5 percent / pyridine 4: ethanol / 2 h / Heating View Scheme