1: 71 percent / sodium dithionite, potassium hydrogen carbonate / H2O; ethanol / 1 h / Ambient temperature 2: sodium nitrite / acetic acid; H2O / 1.) 0 deg C, 0.25 h, 2.) RT, 0.25 h 3: 87 percent / 24 h / Irradiation 4: 65 percent / nickel acetate tetrahydrate / acetic acid / 1 h / Heating 5: 75 percent / conc. ammonia / methanol / 9 h / Ambient temperature View Scheme

1: 66.5 percent / toluene-p-sulphonic acid / CH2Cl2 / 3 h 2: 71 percent / hydrogen peroxide, aq. potassium carbonate / dioxane / 1 h 3: 1.) methanolic ammonia, 2.) toluene-p-sulphonic acid / 1.) 6 h, room temperature 4: 83 percent / H2 / palladium-charcoal / ethanol / 3 h 5: 69 percent / sodium methoxide / methanol / 2 h / Heating View Scheme

1: 66.5 percent / toluene-p-sulphonic acid / CH2Cl2 / 3 h 2: 71 percent / hydrogen peroxide, aq. potassium carbonate / dioxane / 1 h 3: 1.) methanolic ammonia, 2.) toluene-p-sulphonic acid / 1.) 6 h, room temperature 4: 83 percent / H2 / palladium-charcoal / ethanol / 3 h View Scheme