1: triphenylphosphine hydrobromide / acetonitrile / 5 h / 0 - 55 °C / Inert atmosphere 2: copper(I) bromide / dichloromethane / 3 h / Reflux; Inert atmosphere 3: sulfuric acid; acetic acid / 12 h / 0 - 20 °C / Inert atmosphere 4: trimethylsilylazide / tert-butyl alcohol / 10 h / Reflux; Inert atmosphere 5: hydrogen / ethanol / 15 h / 20 °C / 760.05 Torr / Inert atmosphere 6: tetrahydrofuran / 29 h / 50 °C / Inert atmosphere 7: methanol; sodium methylate / 1 h / 20 °C / Inert atmosphere 8: trifluoroacetic acid / dichloromethane / 2.5 h / 20 °C / Inert atmosphere View Scheme

1.1: trimethylsilyl trifluoromethanesulfonate / ethyl acetate / 3 h / 50 °C / |Inert atmosphere 2.1: trimethylsilylazide / tert-butyl alcohol / 12 h / 80 °C / |Inert atmosphere 3.1: triphenylphosphine / tetrahydrofuran / 12 h / 20 °C 3.2: 24 h / 20 °C 4.1: triethylamine; mercury dichloride / N,N-dimethyl-formamide / 5 h / 0 °C 5.1: sodium methylate / methanol / 0.5 h / 0 °C 5.2: 0.5 h / 0 °C 5.3: Amberlite IR-120 resin (NH4+ form 6.1: trifluoroacetic acid / dichloromethane / 5 h / 0 - 20 °C View Scheme