1: 80 percent / lithium hexamethyldisilazide / tetrahydrofuran; hexane / 4 h / -78 °C 2: H2O2, m-chloroperoxybenzoic acid / CHCl3; H2O / 0.75 h / -50 - 0 °C 3: toluene / 5 h / 90 °C 4: NaOH / methanol / 2 h / Ambient temperature 5: 1.) trimethylsilyl chlorid, lithium isopropylamide / 1.) THF/hexane, -78 degC, 3 h 2.) THF, 0 degC, 3 h 6: 58 percent / H2O2 / pyridine; CH2Cl2; H2O / 18 h / Ambient temperature 7: 90 percent / HCl / methanol; H2O / 1 h / Ambient temperature View Scheme