1: toluene-4-sulfonic acid / methanol / 5 h / 20 °C 2: potassium carbonate / acetone / 20 °C / Inert atmosphere 3: diethylaluminium chloride / hexane / 2 h / 20 °C / Inert atmosphere 4: boron tribromide / dichloromethane / 0.42 h / 20 °C / Inert atmosphere 5: palladium 10 on activated carbon; hydrogen / methanol / 2 h / 20 °C / 3102.97 Torr / Inert atmosphere View Scheme