1: 63 percent / zinc, TiCl4 / tetrahydrofuran; CH2Cl2 / 0 °C 2: 1.) NaOH / 1.) dioxane, water, 70 deg C, 16 h, 2.) dioxane, water, room temperature, 2 h 3: 16 mg / diethyl ether 4: CrO3, H2SO4 / acetone / 1 h / 0 °C 5: 9 mg / diethyl ether 6: KOH / tetrahydrofuran / 12 h / Ambient temperature 7: 4.5 mg / trifluoroacetic acid / CH2Cl2 / 12 h View Scheme