1: LDA / tetrahydrofuran / 0.5 h / -78 °C 2: NaBH4 / toluene; ethanol / 8 h / -78 - 0 °C View Scheme

1.1: hydrogenchloride; water / tetrahydrofuran / 4 h / 50 - 55 °C 2.1: benzotriazol-1-ol; triethylamine; thionyl chloride / dichloromethane / 3 h / 0 - 25 °C / |Inert atmosphere 2.2: 12 h / 30 - 35 °C 3.1: tetrabutylammomium bromide; potassium hydroxide / dichloromethane; water / 3 h / 0 - 10 °C 4.1: water / 60 - 65 °C 5.1: hydrogenchloride; water / tetrahydrofuran / 6 h / 60 - 65 °C 6.1: benzotriazol-1-ol; triethylamine; thionyl chloride / dichloromethane / 3.5 h / -5 - 15 °C / |Inert atmosphere 6.2: 16 h / 10 - 35 °C View Scheme