1: SOCl2 2: Na2CO3 / toluene; H2O / 1.) 10 deg C, 0.5 h, 2.) RT, 1 h 3: 83 percent / BH3 / tetrahydrofuran / 1.) reflux, 1h, 2.) overnight 4: 1.) K, EtOH / 1.) Et2O, 10 min, 2.) Et2O, overnight 5: 80 percent / 2percent aq. NaOH, 30percent aq. H2O2 / 1 h / Ambient temperature View Scheme

hydrogenchloride; thionyl chloride; sodium carbonate in water; toluene

1: SOCl2 2: Na2CO3 / toluene; H2O / 1.5 h / 10 - 20 °C View Scheme

1.1: sulfuric acid monomethylester; sodium tetrahydroborate / tetrahydrofuran / 16 h / 10 °C / |Industrial scale 2.1: potassium hydroxide / acetone / 24 h / 25 °C / |Industrial scale 3.1: sodium ethanolate; oxalic acid diethyl ester / tetrahydrofuran / 24 h / 25 °C / |Industrial scale 3.2: 3 h / 0 - 10 °C / |Industrial scale 4.1: palladium 10 on activated carbon; hydrogen; acetic acid / ethyl acetate / 36 h / 40 °C View Scheme

hydrogen; platinum on activated charcoal

1: SOCl2 2: Na2CO3 / toluene; H2O / 1.5 h / 10 - 20 °C 3: 83 percent / borane/THF / 1 h / Heating 4: 1.) EtOK, 3.) H2O 5: aq. NaOH, H2O2 / 1 h / Ambient temperature View Scheme