methanesulfonyl chloride in pyridine 20 h; Ambient temperature;

1: 5.7 g / n-butyl-lithium, diisopropylamide / tetrahydrofuran; hexamethylphosphoric acid triamide; hexane / 0.33 h / -78 °C 2: 70 percent / tetrahydrofuran; H2O / 2 h / Ambient temperature 3: 75 percent / methanesulphonyl chloride / pyridine / 20 h / Ambient temperature View Scheme

1: 95 percent / NBS / 110 - 115 °C 2: 74 percent / anhydr. ZnBr2 / xylene / 8 h / Heating 3: 5.7 g / n-butyl-lithium, diisopropylamide / tetrahydrofuran; hexamethylphosphoric acid triamide; hexane / 0.33 h / -78 °C 4: 70 percent / tetrahydrofuran; H2O / 2 h / Ambient temperature 5: 75 percent / methanesulphonyl chloride / pyridine / 20 h / Ambient temperature View Scheme

1: 74 percent / anhydr. ZnBr2 / xylene / 8 h / Heating 2: 5.7 g / n-butyl-lithium, diisopropylamide / tetrahydrofuran; hexamethylphosphoric acid triamide; hexane / 0.33 h / -78 °C 3: 70 percent / tetrahydrofuran; H2O / 2 h / Ambient temperature 4: 75 percent / methanesulphonyl chloride / pyridine / 20 h / Ambient temperature View Scheme

1: 70 percent / tetrahydrofuran; H2O / 2 h / Ambient temperature 2: 75 percent / methanesulphonyl chloride / pyridine / 20 h / Ambient temperature View Scheme