1: Diisobutylaluminum hydride / toluene / 0.1 h / -78 °C 2: 1.) NaHSO3 / 1.) 5 deg C, overnight, 2.) ethyl acetate, water, room temp., 4 h 3: 90 percent / concentrated HCl / dioxane / 12 h / Heating 4: 73 percent / triethylamine / H2O; dioxane / 25 °C View Scheme

1: Diisobutylaluminum hydride / toluene / 0.1 h / -78 °C 2: 1.) NaHSO3 / 1.) 5 deg C, overnight, 2.) ethyl acetate, water, room temp., 4 h 3: 90 percent / concentrated HCl / dioxane / 12 h / Heating 4: 73 percent / triethylamine / H2O; dioxane / 25 °C 5: 60 percent / diethyl ether / 1 h / 25 °C 6: 100 percent / sodium hydroxide, water / dioxane / pH 10 View Scheme

1: Diisobutylaluminum hydride / toluene / 0.1 h / -78 °C 2: 1.) NaHSO3 / 1.) 5 deg C, overnight, 2.) ethyl acetate, water, room temp., 4 h 3: 90 percent / concentrated HCl / dioxane / 12 h / Heating 4: 73 percent / triethylamine / H2O; dioxane / 25 °C 5: 25 percent / diethyl ether / 1 h / 25 °C 6: 100 percent / aq. sodium hydroxide / dioxane / pH 10 View Scheme

1: Diisobutylaluminum hydride / toluene / 0.1 h / -78 °C 2: 1.) NaHSO3 / 1.) 5 deg C, overnight, 2.) ethyl acetate, water, room temp., 4 h 3: 90 percent / concentrated HCl / dioxane / 12 h / Heating 4: 73 percent / triethylamine / H2O; dioxane / 25 °C 5: 1.) hydrochloric acid, 2.) triethylamine, DCC, HOBt / 1.) dioxane, 30 min, 25 deg C 2.) methylene chloride 6: 1.) TFA, 2.) H2, Pd/C / 1.) room temperature, 30 min 2.) methanol, 24 h View Scheme