1: 79 percent / diisobutylaluminum hydride / diethyl ether / 3.33 h / 25 - 40 °C 2: pyridine, NBS / diethyl ether / 1.25 h / 25 - 30 °C / Irradiation 3: 1.) Br2, 2.) tetrabutylammonium fluoride trihydrate / 1.) CH2Cl2, -78 deg C, 2.) THF, CH2Cl2, -20 deg C 4: 85 percent / EtONa, BHA, Pd(PPh3)4 / toluene; ethanol / 0.75 h / 65 °C 5: pyridinium tosylate, BHA, / ethanol / 3 h / 45 °C View Scheme

1: 85 percent / EtONa, BHA, Pd(PPh3)4 / toluene; ethanol / 0.75 h / 65 °C 2: pyridinium tosylate, BHA, / ethanol / 3 h / 45 °C View Scheme

1: pyridine, NBS / diethyl ether / 1.25 h / 25 - 30 °C / Irradiation 2: 1.) Br2, 2.) tetrabutylammonium fluoride trihydrate / 1.) CH2Cl2, -78 deg C, 2.) THF, CH2Cl2, -20 deg C 3: 85 percent / EtONa, BHA, Pd(PPh3)4 / toluene; ethanol / 0.75 h / 65 °C 4: pyridinium tosylate, BHA, / ethanol / 3 h / 45 °C View Scheme

1: 1.) Br2, 2.) tetrabutylammonium fluoride trihydrate / 1.) CH2Cl2, -78 deg C, 2.) THF, CH2Cl2, -20 deg C 2: 85 percent / EtONa, BHA, Pd(PPh3)4 / toluene; ethanol / 0.75 h / 65 °C 3: pyridinium tosylate, BHA, / ethanol / 3 h / 45 °C View Scheme

1: TEA / CH2Cl2 / 4 h / 0 °C 2: 1.) Mg, 2.) Li2CuCl3 / 1.) THF, 2.) 0 deg C, 3 h 3: 82 percent / PTS / methanol / Ambient temperature View Scheme

potassium hydroxide in methanol

(i) Na<N(SiMe3)2>, (ii) OH-; Multistep reaction;

2: NaCH2SOMe View Scheme

potassium tert-butylate in N,N-dimethyl-formamide 1 h; Ambient temperaturevariation of temp., solvent and base; Product distributionMechanism;