pyridine T=0°C; Yield given;

1: 1.) sodium nitrite, aq. HCl, 2.) sodium nitrite, cuprous oxide / 1.) from -5 deg C to 0 deg C, 10 min, 2.) H2O, from -5 deg C to RT, 60 min 2: 60 percent / potassium carbonate / xylene / 5.5 h / Heating 3: iron, ammonium chloride, H2O / ethanol / 0.5 h / Heating 4: pyridine / 0 °C View Scheme

1: 60 percent / potassium carbonate / xylene / 5.5 h / Heating 2: iron, ammonium chloride, H2O / ethanol / 0.5 h / Heating 3: pyridine / 0 °C View Scheme

1: 60 percent / potassium carbonate / xylene / 5.5 h / Heating 2: iron, ammonium chloride, H2O / ethanol / 0.5 h / Heating 3: pyridine / 0 °C View Scheme

1: dimethylformamide / 10 h / 150 °C 2: 3N aq. HCl / acetone / 2.5 h / Heating 3: iron, ammonium chloride, H2O / ethanol / 0.5 h / Heating 4: pyridine / 0 °C View Scheme

1: iron, ammonium chloride, H2O / ethanol / 0.5 h / Heating 2: pyridine / 0 °C View Scheme

1: 3N aq. HCl / acetone / 2.5 h / Heating 2: iron, ammonium chloride, H2O / ethanol / 0.5 h / Heating 3: pyridine / 0 °C View Scheme