1: tetrabutyl ammonium fluoride / 2 h / 0 °C 2: 1-hydroxy-3H-benz[d][1,2]iodoxole-1,3-dione / dimethyl sulfoxide / 1 h / 25 °C 3: potassium carbonate / methanol / 2 h / 25 °C 4: pyridine; oct-1-ene; hydrogen / ethyl acetate / 6 h / 20 °C 5: Grubb's 2nd generation catalyst / dichloromethane / 14 h / |Reflux 6: ammonium chloride; sodium azide; water / ethanol; N,N-dimethyl-formamide / 10 h / 0 - 25 °C 7: triphenylphosphine / toluene / 3 h / 110 °C 8: 4-(N,N-dimethlyamino)pyridine; triethylamine / dichloromethane / 0.75 h / 0 - 25 °C 9: boron trifluoride diethyl etherate / 0.5 h / -10 °C 10: hydrogenchloride / ethanol; water / 12 h / 25 °C 11: triethylamine / dichloromethane / 1 h / 0 °C 12: sodium azide / N,N-dimethyl-formamide / 3 h / 80 °C View Scheme

1: 1-hydroxy-3H-benz[d][1,2]iodoxole-1,3-dione / dimethyl sulfoxide / 1 h / 25 °C 2: potassium carbonate / methanol / 2 h / 25 °C 3: pyridine; oct-1-ene; hydrogen / ethyl acetate / 6 h / 20 °C 4: Grubb's 2nd generation catalyst / dichloromethane / 14 h / |Reflux 5: ammonium chloride; sodium azide; water / ethanol; N,N-dimethyl-formamide / 10 h / 0 - 25 °C 6: triphenylphosphine / toluene / 3 h / 110 °C 7: 4-(N,N-dimethlyamino)pyridine; triethylamine / dichloromethane / 0.75 h / 0 - 25 °C 8: boron trifluoride diethyl etherate / 0.5 h / -10 °C 9: hydrogenchloride / ethanol; water / 12 h / 25 °C 10: triethylamine / dichloromethane / 1 h / 0 °C 11: sodium azide / N,N-dimethyl-formamide / 3 h / 80 °C View Scheme

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

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

1.1: pyridine; sulfuryl dichloride / dichloromethane / -30 - -20 °C 2.1: perchloric acid / 18 h 3.1: dimethylsulfide borane complex; trimethylsilyl trifluoromethanesulfonate / dichloromethane / 1 h / -30 - -20 °C 3.2: 12 h / 20 °C 3.3: 2 h / 55 - 65 °C 4.1: sodium azide; ammonium chloride / water; ethanol / 8 h / 70 - 75 °C 4.2: 6 h / |Reflux 5.1: sodium azide; ammonium chloride / N,N-dimethyl-formamide / 5 h / 8 - 85 °C 6.1: sodium hydrogencarbonate / water; dichloromethane / 1 h / 20 °C View Scheme

1.1: toluene-4-sulfonic acid / acetone / 2 h / |Reflux; |Large scale 2.1: ethanol / 2 h / 20 °C 2.2: 1 h / 0 - 10 °C 3.1: pyridine; sulfuryl dichloride / dichloromethane / -30 - -20 °C 4.1: perchloric acid / 18 h 5.1: dimethylsulfide borane complex; trimethylsilyl trifluoromethanesulfonate / dichloromethane / 1 h / -30 - -20 °C 5.2: 12 h / 20 °C 5.3: 2 h / 55 - 65 °C 6.1: sodium azide; ammonium chloride / water; ethanol / 8 h / 70 - 75 °C 6.2: 6 h / |Reflux 7.1: sodium azide; ammonium chloride / N,N-dimethyl-formamide / 5 h / 8 - 85 °C 8.1: sodium hydrogencarbonate / water; dichloromethane / 1 h / 20 °C View Scheme

1.1: toluene-4-sulfonic acid / acetone / 2 h / |Reflux; |Large scale 2.1: ethanol / 2 h / 20 °C 2.2: 1 h / 0 - 10 °C 3.1: pyridine; sulfuryl dichloride / dichloromethane / -30 - -20 °C 4.1: perchloric acid / 18 h 5.1: dimethylsulfide borane complex; trimethylsilyl trifluoromethanesulfonate / dichloromethane / 1 h / -30 - -20 °C 5.2: 12 h / 20 °C 5.3: 2 h / 55 - 65 °C 6.1: sodium azide; ammonium chloride / water; ethanol / 8 h / 70 - 75 °C 6.2: 6 h / |Reflux 7.1: sodium azide; ammonium chloride / N,N-dimethyl-formamide / 5 h / 8 - 85 °C 8.1: sodium hydrogencarbonate / water; dichloromethane / 1 h / 20 °C View Scheme

1.1: ethanol / 2 h / 20 °C 1.2: 1 h / 0 - 10 °C 2.1: pyridine; sulfuryl dichloride / dichloromethane / -30 - -20 °C 3.1: perchloric acid / 18 h 4.1: dimethylsulfide borane complex; trimethylsilyl trifluoromethanesulfonate / dichloromethane / 1 h / -30 - -20 °C 4.2: 12 h / 20 °C 4.3: 2 h / 55 - 65 °C 5.1: sodium azide; ammonium chloride / water; ethanol / 8 h / 70 - 75 °C 5.2: 6 h / |Reflux 6.1: sodium azide; ammonium chloride / N,N-dimethyl-formamide / 5 h / 8 - 85 °C 7.1: sodium hydrogencarbonate / water; dichloromethane / 1 h / 20 °C View Scheme

boron trifluoride diethyl etherate T=0°C; 2 h; Molecular sieve; regioselective reaction;

tributylphosphine; acetic acid in ethanol; water T=5 - 25°C; 5.5 - 9 h;