1: sulfuric acid / 24 h / Reflux 2: palladium 10 on activated carbon; hydrogen / methanol / 24 h / 20 °C 3: 1H-imidazole / N,N-dimethyl-formamide / 3 h / 20 °C 4: lithium aluminium tetrahydride / tetrahydrofuran / 1 h / -15 °C 5: 4-(N,N-dimethlyamino)pyridine; dicyclohexyl-carbodiimide / dichloromethane / 4 h / 20 °C 6: tetrabutyl ammonium fluoride / tetrahydrofuran / Inert atmosphere View Scheme