benzenesulfonyl chloride in pyridine T=0°C; 0.25 h; Yield given;

1: 94 percent / TsOH / CH2Cl2 / 0 degC, 30 min, room t., 1 h 2: 0.67 g / NaBH4 / methanol; tetrahydrofuran / 1 h / Ambient temperature 3: 0.61 g / NaOH / H2O; methanol / 4 h / Heating 4: benzenesulfonyl chlorid / pyridine / 0.25 h / 0 °C View Scheme

1: 48 percent / 1.) NaH; 2.) BuLi / tetrahydrofuran; hexane / 1.) 1 h, room t.; 2.) 0 degC, 15 min, room t., 1 h 2: 94 percent / TsOH / CH2Cl2 / 0 degC, 30 min, room t., 1 h 3: 0.67 g / NaBH4 / methanol; tetrahydrofuran / 1 h / Ambient temperature 4: 0.61 g / NaOH / H2O; methanol / 4 h / Heating 5: benzenesulfonyl chlorid / pyridine / 0.25 h / 0 °C View Scheme

1: 48 percent / 1.) NaH; 2.) BuLi / tetrahydrofuran; hexane / 1.) 1 h, room t.; 2.) 0 degC, 15 min, room t., 1 h 2: 94 percent / TsOH / CH2Cl2 / 0 degC, 30 min, room t., 1 h 3: 0.67 g / NaBH4 / methanol; tetrahydrofuran / 1 h / Ambient temperature 4: 0.61 g / NaOH / H2O; methanol / 4 h / Heating 5: benzenesulfonyl chlorid / pyridine / 0.25 h / 0 °C View Scheme

1: 94 percent / TsOH / CH2Cl2 / 0 degC, 30 min, room t., 1 h 2: 0.67 g / NaBH4 / methanol; tetrahydrofuran / 1 h / Ambient temperature 3: 0.61 g / NaOH / H2O; methanol / 4 h / Heating 4: benzenesulfonyl chlorid / pyridine / 0.25 h / 0 °C View Scheme

1: 0.61 g / NaOH / H2O; methanol / 4 h / Heating 2: benzenesulfonyl chlorid / pyridine / 0.25 h / 0 °C View Scheme

1: 0.67 g / NaBH4 / methanol; tetrahydrofuran / 1 h / Ambient temperature 2: 0.61 g / NaOH / H2O; methanol / 4 h / Heating 3: benzenesulfonyl chlorid / pyridine / 0.25 h / 0 °C View Scheme

1: pyridinium p-toluenesulfonate / ethanol / 4 h / 55 °C 2: 26 percent / triphenylphosphine, diethyl azodicarboxylate / tetrahydrofuran / Ambient temperature View Scheme