1: With 1,3,5,7-tetra-azatricyclo[5.1.1.13,5]decane in ethanol T=20°C; 2 h; Heating / reflux; 2: With acetic acid in water T=20°C; 3: With Na2S2O5 in ethanol; water 2 h;

1: 100 percent / ZnCl2 / CH2Cl2 / 1 h / Heating 2: 1.) hexamethylenetetramine, 2.) aq. AcOH / 1.) ethanol, reflux, 90 min, 2.) ethanol, reflux View Scheme

1.1: zinc(II) chloride / dichloromethane / 30 - 35 °C 2.1: 1,3,5,7-tetra-azatricyclo[5.1.1.13,5]decane / methanol; ethanol / 760.05 Torr / |Heating 2.2: 760.05 Torr / |Heating View Scheme

1: 87 percent / AcOH, n-BuNH2 / methanol / 18 h / 22 °C 2: 64 percent / AcCl, FeCl3 / CH2Cl2 / 1 h / 0 - 5 °C 3: hydrazine hydrate, 10percent Pd-C / methanol; H2O / 0.5 h / Heating 4: aq. NaOH / methanol / 0.5 h / Heating 5: 80 percent / pyridine / CH2Cl2 / 5 - 10 °C 6: H2O / 2 h / Heating View Scheme

1: 87 percent / AcOH, n-BuNH2 / methanol / 18 h / 22 °C 2: 64 percent / AcCl, FeCl3 / CH2Cl2 / 1 h / 0 - 5 °C 3: hydrazine hydrate, 10percent Pd-C / methanol; H2O / 0.5 h / Heating View Scheme

1: 87 percent / AcOH, n-BuNH2 / methanol / 18 h / 22 °C 2: 64 percent / AcCl, FeCl3 / CH2Cl2 / 1 h / 0 - 5 °C 3: hydrazine hydrate, 10percent Pd-C / methanol; H2O / 0.5 h / Heating 4: aq. NaOH / methanol / 0.5 h / Heating 5: 87 percent / pyridine / CH2Cl2 / 4 h / 5 - 10 °C View Scheme

1: 87 percent / AcOH, n-BuNH2 / methanol / 18 h / 22 °C 2: 64 percent / AcCl, FeCl3 / CH2Cl2 / 1 h / 0 - 5 °C View Scheme

1: 87 percent / AcOH, n-BuNH2 / methanol / 18 h / 22 °C 2: 64 percent / AcCl, FeCl3 / CH2Cl2 / 1 h / 0 - 5 °C 3: hydrazine hydrate, 10percent Pd-C / methanol; H2O / 0.5 h / Heating 4: aq. NaOH / methanol / 0.5 h / Heating View Scheme