hydrogenchloride in methanol; dichloromethane 2 h; Ambient temperature;

1: 50percent aq. sodium hydroxide / tetrabutylammonium hydrogen sulfate / 72 h / 65 °C 2: aq. HCl / methanol; CH2Cl2 / 2 h / Ambient temperature 3: 50percent aq. sodium hydroxide / tetrabutylammonium hydrogen sulfate / 72 h / 65 °C 4: aq. HCl / methanol; CH2Cl2 / 2 h / Ambient temperature View Scheme

1: 50percent aq. sodium hydroxide / tetrabutylammonium hydrogen sulfate / 72 h / 65 °C 2: aq. HCl / methanol; CH2Cl2 / 2 h / Ambient temperature View Scheme

sodium hydroxide; p-toluenesulfonyl chloride in 1,4-dioxane T=60°C; 24 h;