1: 72 percent / 30percent aq. H2O2, 6N aq. NaOH / ethanol / 4 h / Ambient temperature 2: 1.) Pb(OAc)4, 2.) trifluoroacetic acid / 1.) tert-butyl alcohol, reflux, 1,5 h, 2.) room temp., 1 h 3: 45 percent / n-BuLi / tetrahydrofuran / 2 h / -70 °C View Scheme

1: 81 percent / H2O / ethyl acetate / 0.2 h / 20 °C 2: 79 percent / aq. HCl / dioxane / 12 h / Heating View Scheme

1: 72 percent / 30percent aq. H2O2, 6N aq. NaOH / ethanol / 4 h / Ambient temperature 2: 1.) Pb(OAc)4, 2.) trifluoroacetic acid / 1.) tert-butyl alcohol, reflux, 1,5 h, 2.) room temp., 1 h View Scheme