1: sulfuric acid / 24 h / Reflux 2: lithium / methanol / 48 h / Reflux 3: sulfuric acid / 24 h / Reflux 4: palladium 10 on activated carbon; hydrogen / methanol / 24 h / 20 °C 5: 1H-imidazole / N,N-dimethyl-formamide / 3 h / 20 °C 6: lithium aluminium tetrahydride / tetrahydrofuran / 1 h / -15 °C 7: 4-(N,N-dimethlyamino)pyridine; dicyclohexyl-carbodiimide / dichloromethane / 4 h / 20 °C 8: tetrabutyl ammonium fluoride / tetrahydrofuran / Inert atmosphere View Scheme

1: lithium / methanol / 48 h / Reflux 2: sulfuric acid / 24 h / Reflux 3: palladium 10 on activated carbon; hydrogen / methanol / 24 h / 20 °C 4: 1H-imidazole / N,N-dimethyl-formamide / 3 h / 20 °C 5: lithium aluminium tetrahydride / tetrahydrofuran / 1 h / -15 °C 6: 4-(N,N-dimethlyamino)pyridine; dicyclohexyl-carbodiimide / dichloromethane / 4 h / 20 °C 7: tetrabutyl ammonium fluoride / tetrahydrofuran / Inert atmosphere View Scheme

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

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

1: 1H-imidazole / N,N-dimethyl-formamide / 3 h / 20 °C 2: lithium aluminium tetrahydride / tetrahydrofuran / 1 h / -15 °C 3: 4-(N,N-dimethlyamino)pyridine; dicyclohexyl-carbodiimide / dichloromethane / 4 h / 20 °C 4: tetrabutyl ammonium fluoride / tetrahydrofuran / Inert atmosphere View Scheme

1: lithium / methanol / 48 h / Reflux 2: sulfuric acid / 24 h / Reflux 3: lithium / methanol / 48 h / Reflux 4: sulfuric acid / 24 h / Reflux 5: palladium 10 on activated carbon; hydrogen / methanol / 24 h / 20 °C 6: 1H-imidazole / N,N-dimethyl-formamide / 3 h / 20 °C 7: lithium aluminium tetrahydride / tetrahydrofuran / 1 h / -15 °C 8: 4-(N,N-dimethlyamino)pyridine; dicyclohexyl-carbodiimide / dichloromethane / 4 h / 20 °C 9: tetrabutyl ammonium fluoride / tetrahydrofuran / Inert atmosphere View Scheme