1.1: pyridine / dichloromethane / 0.25 h / 30 - 35 °C 1.2: 5.5 h / 30 - 35 °C 2.1: anhydrous iron chloride / dichloromethane / 5 - 40 °C 3.1: potassium methylate / methanol / 2 h / 60 °C View Scheme

1: With triethylamine; benzenesulfonyl chloride in tert-butyl methyl ether; toluene T=80°C; 2 h; 2: With water in tert-butyl methyl ether; toluene T=50°C;

1.1: trifluoroacetic acid / 18 h / 70 °C 1.2: 20 °C 2.1: potassium carbonate / N,N-dimethyl-formamide / 1 h / 50 °C 2.2: 5 h / 75 °C 3.1: water; sodium hydroxide / tert-butyl methyl ether / 20 °C 4.1: benzenesulfonyl chloride; triethylamine / tert-butyl methyl ether; toluene / 2 h / 80 °C 4.2: 50 °C View Scheme

1.1: potassium carbonate / N,N-dimethyl-formamide / 1 h / 50 °C 1.2: 5 h / 75 °C 2.1: water; sodium hydroxide / tert-butyl methyl ether / 20 °C 3.1: benzenesulfonyl chloride; triethylamine / tert-butyl methyl ether; toluene / 2 h / 80 °C 3.2: 50 °C View Scheme

1.1: water; sodium hydroxide / tert-butyl methyl ether / 20 °C 2.1: benzenesulfonyl chloride; triethylamine / tert-butyl methyl ether; toluene / 2 h / 80 °C 2.2: 50 °C View Scheme

1.1: potassium carbonate / N,N-dimethyl-formamide / 1 h / 50 °C 1.2: 5 h / 75 °C 2.1: water; sodium hydroxide / tert-butyl methyl ether / 20 °C 3.1: benzenesulfonyl chloride; triethylamine / tert-butyl methyl ether; toluene / 2 h / 80 °C 3.2: 50 °C View Scheme