1: 32 g / acetic acid / 1 h / 25 °C 2: 88 percent / 4percent KOH / methanol; diethyl ether / 2 h / 25 °C 3: 30percent H2O2 / tetrahydrofuran; H2O / 2.5 h / 25 °C 4: tetrahydrofuran; H2O / 2 h / 55 °C 5: 20.6 g / Jones reagent / tetrahydrofuran; H2O; acetone / 0.25 h 6: 1.) THF, -20 deg C, 30 min, 2.) -78 deg C 7: 38 g / Et3N / CH2Cl2 / 0.5 h / -5 °C 8: 28.09 g / DBU / benzene / 1 h / 25 °C 9: 78 percent / H2 / 10percent Pd/C / benzene; pyridine / 0.67 h / 25 °C 10: Et3N, Na2SO4 / ethanol / 7 h / 25 °C 11: 5.3 g / LDA / tetrahydrofuran; hexane / -78 deg C -> 0 deg C, 1 h; 0 deg C, 4 h 12: 100 percent / Li, NH3 liq. / tetrahydrofuran / 0.5 h 13: 1 mg / 4-(dimethylamino)pyridine / pyridine / 16 h / 25 °C 14: 2.8 g / pyridine / 8 h / 0 °C 15: 1.8 g / DBU / pyridine / 3 h / Heating 16: 1.44 g / acetic acid; tetrahydrofuran; H2O / 8 h / 25 °C 17: 65 percent / pyridinium chlorochromate / CH2Cl2 / 4 h / 25 °C 18: 1.) NaH, 2.) n-BuLi / 1.) THF, 0 deg C, 10 min, 2.) THF-hexane, 0 deg C, 10 min, 3.) 0 deg C, 15 min 19: 34 mg / Zn(BH4)2 / diethyl ether / 1 h / 25 °C 20: 32 mg / p-toluenesulfonic acid monohydrate / benzene / 0.25 h / 25 °C View Scheme