1: With lithium borohydride; chloro-trimethyl-silane in tetrahydrofuran T=20°C; 72.58 h; 2: With methanol in tetrahydrofuran 1 h; 3: With hydrogenchloride in diethyl ether 0.5 h;

1: With borane-THF in tetrahydrofuran Heating / reflux; 2: With hydrogenchloride in water

1: triethylamine / tetrahydrofuran / 20 °C / |Cooling with ice 2: potassium carbonate / acetone / 19 h / 50 °C 3: hydrogenchloride / 1,4-dioxane; water / 3.5 h / 20 °C View Scheme

1.1: hydrogen bromide; acetic acid / 4 h / |Reflux 2.1: triethylamine / N,N-dimethyl-formamide; 1,4-dioxane / 0.25 h 2.2: 18 h / 20 °C 3.1: caesium carbonate / acetonitrile / 24 h 4.1: hydrogenchloride / water; diethyl ether / 2 h / 20 °C View Scheme

1.1: triethylamine / N,N-dimethyl-formamide; 1,4-dioxane / 0.25 h 1.2: 18 h / 20 °C 2.1: caesium carbonate / acetonitrile / 24 h 3.1: hydrogenchloride / water; diethyl ether / 2 h / 20 °C View Scheme

sodium hydroxide in dichloromethane; water