1: sodium azide; ammonium chloride / methanol / 6.5 h / 10 - 20 °C 2: toluene / 1 h / 20 °C 3: toluene / 7 h / |Reflux 4: boron trifluoride diethyl etherate / 17 h / 0 - 20 °C 5: sulfuric acid / ethanol / 16 h / 78 °C 6: sodium carbonate / 0.5 h / 20 °C / pH 6.5 - 7 7: sodium azide / water; ethanol / 24 h / |Reflux View Scheme

1: toluene / 1 h / 20 °C 2: toluene / 7 h / |Reflux 3: boron trifluoride diethyl etherate / 17 h / 0 - 20 °C 4: sulfuric acid / ethanol / 16 h / 78 °C 5: sodium carbonate / 0.5 h / 20 °C / pH 6.5 - 7 6: sodium azide / water; ethanol / 24 h / |Reflux View Scheme

1.1: 1H-imidazole; 4-(N,N-dimethlyamino)pyridine / dichloromethane / 24 h / 20 °C / |Inert atmosphere 2.1: pyridine / dichloromethane / 1 h / -15 °C / |Inert atmosphere 3.1: sodium azide / N,N-dimethyl-formamide / 2 h / 20 °C 4.1: triphenylphosphine / tetrahydrofuran / 4 h / 20 °C 4.2: 4 h / 20 °C 5.1: pyridine / 2 h / 0 - 20 °C 6.1: tetrabutyl ammonium fluoride / tetrahydrofuran / 4 h / 20 °C / |Inert atmosphere 7.1: dimethyl sulfoxide; oxalyl dichloride / dichloromethane / 1 h / -78 °C / |Inert atmosphere 7.2: 0.75 h / -78 - 20 °C / |Inert atmosphere 8.1: titanium tetrachloride / dichloromethane / 0.25 h / 0 °C / |Inert atmosphere 8.2: 2 h / 0 °C / |Inert atmosphere 9.1: 10 Pd/C; hydrogen / ethanol / 96 h / 20 °C 10.1: sodium hydride / tetrahydrofuran / 1 h / 0 °C / |Inert atmosphere 11.1: triethylamine / dichloromethane / 0.75 h / 0 °C 12.1: sodium azide / ethanol; water / 8 h / |Reflux View Scheme

1.1: pyridine / dichloromethane / 1 h / -15 °C / |Inert atmosphere 2.1: sodium azide / N,N-dimethyl-formamide / 2 h / 20 °C 3.1: triphenylphosphine / tetrahydrofuran / 4 h / 20 °C 3.2: 4 h / 20 °C 4.1: pyridine / 2 h / 0 - 20 °C 5.1: tetrabutyl ammonium fluoride / tetrahydrofuran / 4 h / 20 °C / |Inert atmosphere 6.1: dimethyl sulfoxide; oxalyl dichloride / dichloromethane / 1 h / -78 °C / |Inert atmosphere 6.2: 0.75 h / -78 - 20 °C / |Inert atmosphere 7.1: titanium tetrachloride / dichloromethane / 0.25 h / 0 °C / |Inert atmosphere 7.2: 2 h / 0 °C / |Inert atmosphere 8.1: 10 Pd/C; hydrogen / ethanol / 96 h / 20 °C 9.1: sodium hydride / tetrahydrofuran / 1 h / 0 °C / |Inert atmosphere 10.1: triethylamine / dichloromethane / 0.75 h / 0 °C 11.1: sodium azide / ethanol; water / 8 h / |Reflux View Scheme

1.1: triphenylphosphine / tetrahydrofuran / 4 h / 20 °C 1.2: 4 h / 20 °C 2.1: pyridine / 2 h / 0 - 20 °C 3.1: tetrabutyl ammonium fluoride / tetrahydrofuran / 4 h / 20 °C / |Inert atmosphere 4.1: dimethyl sulfoxide; oxalyl dichloride / dichloromethane / 1 h / -78 °C / |Inert atmosphere 4.2: 0.75 h / -78 - 20 °C / |Inert atmosphere 5.1: titanium tetrachloride / dichloromethane / 0.25 h / 0 °C / |Inert atmosphere 5.2: 2 h / 0 °C / |Inert atmosphere 6.1: 10 Pd/C; hydrogen / ethanol / 96 h / 20 °C 7.1: sodium hydride / tetrahydrofuran / 1 h / 0 °C / |Inert atmosphere 8.1: triethylamine / dichloromethane / 0.75 h / 0 °C 9.1: sodium azide / ethanol; water / 8 h / |Reflux View Scheme

1.1: tetrabutyl ammonium fluoride / tetrahydrofuran / 4 h / 20 °C / |Inert atmosphere 2.1: dimethyl sulfoxide; oxalyl dichloride / dichloromethane / 1 h / -78 °C / |Inert atmosphere 2.2: 0.75 h / -78 - 20 °C / |Inert atmosphere 3.1: titanium tetrachloride / dichloromethane / 0.25 h / 0 °C / |Inert atmosphere 3.2: 2 h / 0 °C / |Inert atmosphere 4.1: 10 Pd/C; hydrogen / ethanol / 96 h / 20 °C 5.1: sodium hydride / tetrahydrofuran / 1 h / 0 °C / |Inert atmosphere 6.1: triethylamine / dichloromethane / 0.75 h / 0 °C 7.1: sodium azide / ethanol; water / 8 h / |Reflux View Scheme

1.1: dimethyl sulfoxide; oxalyl dichloride / dichloromethane / 1 h / -78 °C / |Inert atmosphere 1.2: 0.75 h / -78 - 20 °C / |Inert atmosphere 2.1: titanium tetrachloride / dichloromethane / 0.25 h / 0 °C / |Inert atmosphere 2.2: 2 h / 0 °C / |Inert atmosphere 3.1: 10 Pd/C; hydrogen / ethanol / 96 h / 20 °C 4.1: sodium hydride / tetrahydrofuran / 1 h / 0 °C / |Inert atmosphere 5.1: triethylamine / dichloromethane / 0.75 h / 0 °C 6.1: sodium azide / ethanol; water / 8 h / |Reflux View Scheme

1.1: titanium tetrachloride / dichloromethane / 0.25 h / 0 °C / |Inert atmosphere 1.2: 2 h / 0 °C / |Inert atmosphere 2.1: 10 Pd/C; hydrogen / ethanol / 96 h / 20 °C 3.1: sodium hydride / tetrahydrofuran / 1 h / 0 °C / |Inert atmosphere 4.1: triethylamine / dichloromethane / 0.75 h / 0 °C 5.1: sodium azide / ethanol; water / 8 h / |Reflux View Scheme

1: sodium hydride / tetrahydrofuran / 1 h / 0 °C / |Inert atmosphere 2: triethylamine / dichloromethane / 0.75 h / 0 °C 3: sodium azide / ethanol; water / 8 h / |Reflux View Scheme

1: sulfuric acid / ethanol / 16 h / 78 °C 2: sodium carbonate / 0.5 h / 20 °C / pH 6.5 - 7 3: sodium azide / water; ethanol / 24 h / |Reflux View Scheme