potassium carbonate in dichloromethane 6 h;

lithium hexamethyldisilazane in tetrahydrofuran T=24°C; 1 h;

1: 46 percent / sodium nitrite / H2O; dioxane / 6 h / 80 °C 2: potassium carbonate / CH2Cl2 / 6 h / 20 °C View Scheme

1: 48 percent / sodium azide; ammonium cerium(IV) nitrate / acetonitrile / 12 h / -15 °C 2: 46 percent / sodium nitrite / H2O; dioxane / 6 h / 80 °C 3: potassium carbonate / CH2Cl2 / 6 h / 20 °C View Scheme

1: 92 percent / H2NNH2, AcOH / dimethylformamide / 0.03 h / 50 °C 2: LiN(TMS)2 / tetrahydrofuran / 1 h / 24 °C View Scheme

1: trifluoromethanesulfonyl azide; copper(II) sulfate; potassium carbonate / methanol; water / 24 h / -10 - 20 °C / |Inert atmosphere 2: 4-(N,N-dimethlyamino)pyridine; pyridine / 12 h / 0 - 20 °C 3: hydrazinium monoacetate / N,N-dimethyl-formamide / 1 h / 0 - 20 °C / |Inert atmosphere 4: potassium carbonate / dichloromethane / 2 h / 20 °C / |Inert atmosphere View Scheme