1: 95 percent / NaH / dimethylformamide / 1 h / 0 - 20 °C 2: 95 percent / n-BuLi / hexane; diethyl ether / 3 h / -78 - 20 °C 3: 94 percent / aq. HCl / tetrahydrofuran / 2 h / 20 °C 4: 72 percent / K2CO3 / acetone / 1 h / 20 °C 5: 90 percent / Cs2CO3 / dimethylformamide / 1 h / 20 °C 6: 86 percent / n-BuLi / tetrahydrofuran; hexane / 3.25 h / -78 - 20 °C 7: 98 percent / Dess-Martin periodinane / CH2Cl2 / 0.75 h / 20 °C 8: 79 percent / H2 / Pd/C / ethanol / 1 h / 20 °C / 760 Torr 9: 95 percent / Dess-Martin periodinane / CH2Cl2 / 1 h / 20 °C 10: aq. NaH2PO4; NaClO2; 2-methyl-2-butene / tetrahydrofuran; 2-methyl-propan-2-ol / 1 h / 20 °C 11: 203 mg / diethyl ether; methanol / 0.17 h / 20 °C 12: 81 percent / p-TsOH / methanol / 4 h / Heating View Scheme