1: 46.9 g / ethanol / 1 h / Ambient temperature 2: 1.) NaH / 1.) DMF, 30 min, 2.) DMF, RT, 2 h 3: 277 mg / DIBAL-H / toluene / 1 h / -74 °C 4: 71.2 percent / 4-methylmorpholine-N-oxide, tetrapropyl-ammonium perruthenate, molecular sieves 4 Angstroem / CH2Cl2 / 2 h 5: 71.3 percent / acetonitrile / 14 h / Heating 6: 13 g / HF / acetonitrile / 1.5 h / Ambient temperature 7: 1.) Et2BOMe, 2.) NaBH4 / 1.) THF, MeOH, -78 deg C, 30 min, 2.) THF, MeOH, 3 h View Scheme

1: 277 mg / DIBAL-H / toluene / 1 h / -74 °C 2: 71.2 percent / 4-methylmorpholine-N-oxide, tetrapropyl-ammonium perruthenate, molecular sieves 4 Angstroem / CH2Cl2 / 2 h 3: 71.3 percent / acetonitrile / 14 h / Heating 4: 13 g / HF / acetonitrile / 1.5 h / Ambient temperature 5: 1.) Et2BOMe, 2.) NaBH4 / 1.) THF, MeOH, -78 deg C, 30 min, 2.) THF, MeOH, 3 h View Scheme

1.1: acetonitrile / 12 h / 84 °C 2.1: hydrogen fluoride / acetonitrile / 6.5 h / 0 - 28 °C 2.2: 0.33 h / pH 8 3.1: diethyl methoxy borane / tetrahydrofuran; methanol / 1.5 h / -85 °C / Inert atmosphere 3.2: 12.5 h / -85 - 30 °C View Scheme

1.1: sodium hydroxide; water / acetonitrile / 2 h / 20 °C / pH 12.5 1.2: pH 5 2.1: toluene / 22 h / 20 °C / Reflux View Scheme

1: With ethanol; sodium hydroxide T=0 - 20°C; 2: With hydrogenchloride in water; ethyl acetate pH=3.5 - 4.0; Product distribution / selectivity;

1: 1H-imidazole / N,N-dimethyl-formamide / 12 h / 20 °C 2: lithium hydroxide hydrate / methanol / 12 h / 20 °C View Scheme