1: 75 percent / Me3Al / CH2Cl2 / 4 h / 0 °C 2: NaBH4 / ethanol / 0 °C 3: 92 percent / imidazole; 4-DMAP / CH2Cl2 4: 62 percent / bromotrimethylsilane / CH2Cl2 5: 95 percent / CH2Cl2 6: 93 percent / chromous chloride / tetrahydrofuran / 20 °C 7: 99 percent / n-Bu4NF / dimethylformamide 8: 99 percent / CH2Cl2 9: 92 percent / Zn / benzene / Heating 10: 83 percent / Dess-Martin periodinane / CH2Cl2 11: 96 percent / toluene / Heating 12: 99 percent / HF / acetonitrile 13: NaH / CH2Cl2 View Scheme