1: hydrogenchloride / water; dimethyl sulfoxide / 40 - 75 °C 2: tetra-n-octylammonium bromide; potassium hydroxide / water / 1 h / 70 °C 3: sodium hydroxide; water / ethanol / 80 °C View Scheme

1: hydrogenchloride / dimethyl sulfoxide; water / 1.33 h / 40 - 75 °C 2: potassium hydroxide; tetra-n-octylammonium bromide / water / 1 h / 70 °C 3: sodium hydroxide; water / ethanol / 80 °C 4: thionyl chloride / toluene / 0.5 h / 60 °C 5: triethylamine; 4-(N,N-dimethlyamino)pyridine / toluene / 2 h 6: hydrogenchloride; water / acetonitrile / 40 - 45 °C View Scheme

1: hydrogenchloride / water; dimethyl sulfoxide / 40 - 75 °C 2: tetra-n-octylammonium bromide; potassium hydroxide / water / 1 h / 70 °C 3: sodium hydroxide; water / ethanol / 80 °C 4: thionyl chloride / toluene / 60 °C 5: triethylamine / dichloromethane / 0 - 20 °C 6: hydrogen / 5 palladium on charcoal / tetrahydrofuran / 96 h / 50 °C / 2250.23 - 3000.3 Torr / autoclave; Inert atmosphere View Scheme

1: hydrogenchloride / water; dimethyl sulfoxide / 40 - 75 °C 2: tetra-n-octylammonium bromide; potassium hydroxide / water / 1 h / 70 °C View Scheme