1: 96 percent / Br2 / diethyl ether / 1 h / -78 °C 2: 53 percent / t-BuOK / 2-methyl-propan-2-ol / 0.5 h / 75 °C 3: 100 percent / n-Bu4NF / tetrahydrofuran / 2 h / 0 °C 4: Dess-Martin periodinane / CH2Cl2 / 2 h / 0 °C 5: NaClO2; NH2SO3H; Na2HPO4 / H2O; 2-methyl-propan-2-ol / 0.5 h / 20 °C 6: Et3N; DMAP; 1-hydroxybenzotriazol / N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride / CH2Cl2 / 16 h / 20 °C View Scheme