1: thionyl chloride / 2.25 h / 0 °C 2: 18-crown-6 ether / acetonitrile / 13 h / 20 °C 3: hydrogen; ammonium hydroxide / ethanol / 22 h / 20 °C View Scheme

1: 1,4-dioxane / 26 h / |Reflux 2: lithium aluminium tetrahydride / tetrahydrofuran / 3 h / 0 °C / |Inert atmosphere 3: thionyl chloride / 2.25 h / 0 °C 4: 18-crown-6 ether / acetonitrile / 13 h / 20 °C 5: hydrogen; ammonium hydroxide / ethanol / 22 h / 20 °C View Scheme

1: lithium aluminium tetrahydride / tetrahydrofuran / 3 h / 0 °C / |Inert atmosphere 2: thionyl chloride / 2.25 h / 0 °C 3: 18-crown-6 ether / acetonitrile / 13 h / 20 °C 4: hydrogen; ammonium hydroxide / ethanol / 22 h / 20 °C View Scheme

1: 18-crown-6 ether / acetonitrile / 13 h / 20 °C 2: hydrogen; ammonium hydroxide / ethanol / 22 h / 20 °C View Scheme

sodium azide; sulfuric acid 1.) 70 deg C, 2 h, 2.) RT, 12 h;