hydrogen; palladium on activated charcoal

sodium hydroxide; sodium tetrahydroborate in water T=30°C; 20 h;

water; sodium hydroxide in ethanol Cannizzaro reaction; 23 h; Reflux;

sodium tetrahydroborate in ethanol Ambient temperature;

1: 90.6 percent / NaOMe / methanol / 1.) 1 h, -10 deg C, 2.) 16 h, room temperature 2: 86.4 percent / aq. KOH / ethanol / 1 h 3: 52.4 percent / Heating 4: 76.7 percent / p-TsOH / benzene / 4 h / Heating 5: 1.) n-BuLi / 1.) THF, hexane, -82 deg C, 1 h, 2.) THF, 2 h 6: 25.8 percent / 0.2 N aq. HCl / dioxane / 48 h / Heating 7: 36.3 percent / pyridiniumdichromat / CH2Cl2 / 18 h View Scheme

1: 93.2 percent / p-TsOH / 65 h / Heating 2: 1.) n-BuLi / 1.) THF, hexane, 1 h, -78 deg C, 2.a) THF, 2 h, -78 deg C, 2.b) 30 min, room temperature 3: 41.6 percent / 0.2 N aq. HCl / dioxane / 90 h / Ambient temperature 4: 36.3 percent / pyridiniumdichromat / CH2Cl2 / 18 h View Scheme

dipyridinium dichromate in dichloromethane 18 h;

1: 76.7 percent / p-TsOH / benzene / 4 h / Heating 2: 1.) n-BuLi / 1.) THF, hexane, -82 deg C, 1 h, 2.) THF, 2 h 3: 25.8 percent / 0.2 N aq. HCl / dioxane / 48 h / Heating 4: 36.3 percent / pyridiniumdichromat / CH2Cl2 / 18 h View Scheme

1: 65 percent / concd H2SO4, K2Cr2O7 / H2O; benzene / 3 h / 55 °C 2: concd NH4OH, Zn, CuSO4 / H2O / 72 h / Heating View Scheme

1: 1.) LDA / 1.) THF, -78 deg C, 2.) THF, -78 deg C 2: 58 percent / NaBH4 / ethanol / Ambient temperature View Scheme