toluene-4-sulfonic acid in toluene 30 h; Heating;

N-bromosuccinmide in chloroform 0.5 h; Ambient temperature;

lithium hexamethyldisilazane in tetrahydrofuran T=0 - 20°C; 16 h;

1: 1.) polystyryl diphenylphosphine-iodine complex / 1.) CH3CN, room temp., 10 min, 2.) CH3CN, 4 h 2: 92 percent / NBS / CHCl3 / 0.5 h / Ambient temperature View Scheme

chlorine in dichloromethane T=18°C; 0.5 h; Yield given;

1: m-chloroperbenzoic acid (MCPBA) / CHCl3 / 0.05 h / 0 °C 2: 1.) p-toluenesulfonic acid (PTSA), 2.) PTSA / 1.) C6H6, DMF, 50 deg C, 19 h, 2.) C6H6, reflux, 2.5 h 3: 90.2 percent / p-toluenesulfonic acid monohydrate (PTSA) / benzene / 5 h / Heating 4: 0.4968 g / 35percent aq. H2O2, acetic acid / 1 h / 15 - 20 °C 5: 1.) p-toluenesulfonic acid (PTSA), 2.) PTSA / 1.) C6H6, DMF, 50 deg C, 24 h, 2.) C6H6, reflux, 2.5 h View Scheme

1: 1.) p-toluenesulfonic acid (PTSA), 2.) PTSA / 1.) C6H6, DMF, 50 deg C, 19 h, 2.) C6H6, reflux, 2.5 h 2: 90.2 percent / p-toluenesulfonic acid monohydrate (PTSA) / benzene / 5 h / Heating 3: 0.4968 g / 35percent aq. H2O2, acetic acid / 1 h / 15 - 20 °C 4: 1.) p-toluenesulfonic acid (PTSA), 2.) PTSA / 1.) C6H6, DMF, 50 deg C, 24 h, 2.) C6H6, reflux, 2.5 h View Scheme

sulfuryl dichloride in tetrachloromethane; dichloromethane T=-14°C; 3 h;

1: 71 percent / acetone / 1 h / Heating 2: 1.) p-toluenesulfonic acid, 2.) aq. potassium carbonate / 1.) benzene, 19 h reflux 2.) methanol, 10 min 3: 10 percent / p-toluenesulfonic acid / toluene / 30 h / Heating View Scheme

1: 1.) p-toluenesulfonic acid, 2.) aq. potassium carbonate / 1.) benzene, 19 h reflux 2.) methanol, 10 min 2: 10 percent / p-toluenesulfonic acid / toluene / 30 h / Heating View Scheme