potassium hydroxide in dimethyl sulfoxide T=90 - 100°C; 4.5 h;

1: sulfuryl chloride / diethyl ether / 16 h / 25 °C 2: 98 percent / potassium carbonate / acetone / 21 h / Heating 3: 66 percent / boron trichloride / CH2Cl2 / 1.) -78 deg C, 1 h, 2.) RT, 4 h 4: 88 percent / potassium carbonate / acetone / 22 h / Heating 5: 80 percent / potassium hydroxide / dimethylsulfoxide / 4.5 h / 90 - 100 °C View Scheme

1: 98 percent / potassium carbonate / acetone / 21 h / Heating 2: 66 percent / boron trichloride / CH2Cl2 / 1.) -78 deg C, 1 h, 2.) RT, 4 h 3: 88 percent / potassium carbonate / acetone / 22 h / Heating 4: 80 percent / potassium hydroxide / dimethylsulfoxide / 4.5 h / 90 - 100 °C View Scheme

1: 88 percent / potassium carbonate / acetone / 22 h / Heating 2: 80 percent / potassium hydroxide / dimethylsulfoxide / 4.5 h / 90 - 100 °C View Scheme

1: 66 percent / boron trichloride / CH2Cl2 / 1.) -78 deg C, 1 h, 2.) RT, 4 h 2: 88 percent / potassium carbonate / acetone / 22 h / Heating 3: 80 percent / potassium hydroxide / dimethylsulfoxide / 4.5 h / 90 - 100 °C View Scheme

1: SO2Cl2 2: (i) K2CO3, (ii) aq. KOH View Scheme

(i) K2CO3, (ii) aq. KOH; Multistep reaction;