1: With hydrogenchloride in 1,4-dioxane; water T=80°C; 16 h; 2: With sodium hydrogencarbonate in water

1: potassium carbonate; toluene-4-sulfonic acid; toluene-4-sulfonamide / toluene; ethylene glycol dimethyl ether; methanol / 20 h / 80 °C 2: hydrogenchloride / 1,4-dioxane; water / 16 h / 80 °C View Scheme

1: sodium hydrogencarbonate; 2,2,6,6-tetramethyl-1-piperidinyloxy, free radical / dichloromethane; water / 18 h / 20 °C 2: potassium carbonate; toluene-4-sulfonic acid; toluene-4-sulfonamide / toluene; ethylene glycol dimethyl ether; methanol / 20 h / 80 °C 3: hydrogenchloride / 1,4-dioxane; water / 16 h / 80 °C View Scheme

1: lithium aluminium tetrahydride / tetrahydrofuran / 1 h / -10 °C 2: sodium hydrogencarbonate; 2,2,6,6-tetramethyl-1-piperidinyloxy, free radical / dichloromethane; water / 18 h / 20 °C 3: potassium carbonate; toluene-4-sulfonic acid; toluene-4-sulfonamide / toluene; ethylene glycol dimethyl ether; methanol / 20 h / 80 °C 4: hydrogenchloride / 1,4-dioxane; water / 16 h / 80 °C View Scheme

1: sodium hydrogencarbonate / water / 16 h / 20 °C 2: lithium aluminium tetrahydride / tetrahydrofuran / 1 h / -10 °C 3: sodium hydrogencarbonate; 2,2,6,6-tetramethyl-1-piperidinyloxy, free radical / dichloromethane; water / 18 h / 20 °C 4: potassium carbonate; toluene-4-sulfonic acid; toluene-4-sulfonamide / toluene; ethylene glycol dimethyl ether; methanol / 20 h / 80 °C 5: hydrogenchloride / 1,4-dioxane; water / 16 h / 80 °C View Scheme