1: 1) s-BuLi / 1) THF, cyclohexane, a) -70 deg C, 15 min, b) rt, 3.5 h, 2) -70 deg C to rt, 14 h 2: 81 percent / MnO2 / CH2Cl2 / 10 h / Heating 3: 82 percent / N-bromosuccinimide, benzoyl peroxide / CCl4 / 1.5 h / Heating 4: 1) HCO2K, 18-crown-6, 2) Al2O3 / 1) MeCN, 18 h, reflux, 2) CH2Cl2, MeOH, 36 h 5: 51 percent / BF3*Et2O / tetrahydrofuran / 4 h / Heating View Scheme

1: N-(phenylsulphonyl)-3-methylindole With sec.-butyllithium in tetrahydrofuran; cyclohexane T=-70 - 20°C; 6 h; 2: acetic anhydride in tetrahydrofuran; cyclohexane T=-70°C;

1.1: s-BuLi / tetrahydrofuran; cyclohexane / -70 - 20 °C 1.2: 65 percent / tetrahydrofuran; cyclohexane 2.1: 84 percent / MnO2 / CH2Cl2 View Scheme

1: 82 percent / tin(IV) chloride / CH2Cl2 / 1.) -78 deg C up to -10 deg C, 2 h 2: 19 percent / potassium hydroxide / 0.75 h / Heating View Scheme

1: 96 percent / NBS, benzoyl peroxide / CCl4 / 6 h / Heating 2: 96 percent / tetrahydrofuran; dimethylsulfoxide / 12 h / Ambient temperature 3: H2 / Raney nickel / ethanol / 2 h / 1810.02 Torr 4: aq. NaOH / 2 h / Heating View Scheme

tin(IV) chloride in dichloromethane 1.) -78 deg C up to -10 deg C, 2 h;

1: 96 percent / NBS, benzoyl peroxide / CCl4 / 6 h / Heating 2: 92 percent / K2CO3 / 8 h / Heating 3: 87 percent / NaOH View Scheme

tert.-butyl lithium 1.) THF, -5 degC, 45 min; 2.) THF, -78 degC, 0.5 h; Yield given. Multistep reaction;

1: N-bromosuccinmide / tetrachloromethane / 2 h / 20 °C / |Irradiation 2: ammonium hydroxide; iodine / 4 h / 20 - 60 °C View Scheme