1: With methanol; sodium hydroxide T=50°C; 2 h; 2: With hydrogenchloride in water

1: sodium hydrogencarbonate; sodium hydroxide / 1,4-dioxane; water / 12 h / 20 °C 2: potassium carbonate / N,N-dimethyl-formamide / 12 h / 40 - 50 °C 3: trifluoroacetic acid / dichloromethane / 12 h / 20 °C 4: copper(I) bromide; sodium nitrite; hydrogen bromide / ethanol; water / 0.33 h / 0 - 90 °C 5: sodium hydroxide; methanol / 2 h / 50 °C View Scheme

1.1: ammonium hydroxide; ammonium chloride / 72 h / 180 °C / Autoclave 1.2: 24 h / 100 °C 2.1: sodium hydrogencarbonate; sodium hydroxide / 1,4-dioxane; water / 12 h / 20 °C 3.1: potassium carbonate / N,N-dimethyl-formamide / 12 h / 40 - 50 °C 4.1: trifluoroacetic acid / dichloromethane / 12 h / 20 °C 5.1: copper(I) bromide; sodium nitrite; hydrogen bromide / ethanol; water / 0.33 h / 0 - 90 °C 6.1: sodium hydroxide; methanol / 2 h / 50 °C View Scheme