1: 98 percent / n-Bu4NF / tetrahydrofuran 2: 91 percent / CH2Cl2 / -78 °C 3: 99 percent / benzene / Heating 4: 94 percent / DIBAL-H / tetrahydrofuran / -78 °C 5: 93 percent / CH2Cl2 / -78 °C 6: 75 percent / Me3Al / CH2Cl2 / 4 h / 0 °C 7: NaBH4 / ethanol / 0 °C 8: 92 percent / imidazole; 4-DMAP / CH2Cl2 9: 62 percent / bromotrimethylsilane / CH2Cl2 10: 95 percent / CH2Cl2 11: 93 percent / chromous chloride / tetrahydrofuran / 20 °C 12: 99 percent / n-Bu4NF / dimethylformamide 13: 99 percent / CH2Cl2 14: 92 percent / Zn / benzene / Heating 15: 83 percent / Dess-Martin periodinane / CH2Cl2 16: 96 percent / toluene / Heating 17: 99 percent / HF / acetonitrile 18: NaH / CH2Cl2 View Scheme