1.1: hydrogenchloride / water; tert-butyl methyl ether / 0.5 h / 20 - 25 °C 2.1: thionyl chloride / toluene / 3 h / 75 - 80 °C 3.1: sodium carbonate / toluene; water / 1 h / 0 - 5 °C 4.1: dimethylsulfide borane complex / tetrahydrofuran / 3 h / 20 - 80 °C / Inert atmosphere 4.2: 0.5 h / 0 - 5 °C View Scheme

1.1: hydrogenchloride / water; tert-butyl methyl ether / 0.5 h / 20 - 25 °C 2.1: thionyl chloride / toluene / 3 h / 75 - 80 °C 3.1: sodium carbonate / toluene; water / 1 h / 0 - 5 °C 4.1: dimethylsulfide borane complex / tetrahydrofuran / 3 h / 20 - 80 °C / Inert atmosphere 4.2: 0.5 h / 0 - 5 °C 5.1: hydrogen bromide / water / 3 h / 100 - 105 °C View Scheme