1.1: methanesulfonamide / water; tert-butyl alcohol / 120 h / 0 °C 2.1: toluene-4-sulfonic acid / acetone / 20 °C 3.1: lithium chloride; sodium tetrahydroborate / ethanol / 20 °C 4.1: triethylamine / dichloromethane / 3 h / 0 - 20 °C 5.1: Lyndlar catalyst; hydrogen / ethyl acetate / 6 h / 20 °C 5.2: |Reflux 6.1: hydrogenchloride; water; palladium 10 on activated carbon; hydrogen / methanol; ethyl acetate / 48 h / 20 °C View Scheme