1: 100 percent / PtO2, hydrogen / ethanol / Ambient temperature 2: 87 percent / 90percent aqueous CF3COOH / 3.5 h / 0 °C 3: 57 percent / lead tetraacetate / CH2Cl2 / 1.25 h / -10 °C 4: 1.) n-BuLi, 2.) HMPA / 1.) THF, hexane, -100 deg C, 2 min, 2.) THF, hexane, from -100 deg C to RT 5: 61 percent / tetra-n-butylammonium fluoride / tetrahydrofuran / 15 h / Ambient temperature 6: potassium carbonate / methanol; H2O / 7.5 h / Ambient temperature 7: AcOH / H2O View Scheme