manganese(IV) oxide in benzene Ambient temperature;

hydrogenchloride in methanol 12 h; Heating;

hydrogen fluoride in water

1: NaBH4 / ethanol / 0.67 h 2: 4.6 g / TsOH*H2O / toluene / 0.5 h / 110 °C View Scheme

acetic acid 3 h; Heating;

1: 37 percent / pyridine, DMAP / 50 °C 2: 93 percent / MeONa / methanol 3: CH2Cl2; hexane / Ambient temperature 4: pyridine, DMAP / Ambient temperature 5: 96 percent / 10-camphorsulfonic acid / methanol / Ambient temperature 6: aq. NaIO4 / acetone / 0 °C 7: NaBH4 / methanol / 0 °C 8: MeONa / methanol 9: 10-camphosulfonic acid / 0 °C 10: pyridine 11: 15-crown-5 / dimethylformamide / 60 °C 12: DIBAL-H / CH2Cl2 / -78 °C 13: CrCl2 / tetrahydrofuran / 3 h / Ambient temperature 14: 89 percent / 10-camforsulfonic acid / methanol / 60 °C 15: 71 percent / Ph3P, diethyl azodicarboxylate / toluene / 36 h / Heating 16: 56 percent / tert-BuLi / tetrahydrofuran; hexamethylphosphoric acid triamide / 1.) -78 deg C, 10 min, 2.) -78 deg C, 30 min 17: NCS, aq. AgNO3, 2,4,6-collidine / acetonitrile / 0.02 h / 0 °C 18: 65 percent / NaBH(OAc)3 / acetonitrile; acetic acid / 5 h / 0 °C 19: 82 percent / TBAF / tetrahydrofuran / Ambient temperature 20: 87 percent / MnO2 / CH2Cl2 / 3 h / Ambient temperature View Scheme

1: imidazole / dimethylformamide / 14 h / 25 °C 2: NaH / dimethylformamide / 1.) 0 deg C, 30 min, 2.) 25 deg C, 1 h 3: 86 percent / H2 / PdCl2 / methanol / 0.33 h 4: 99 percent / Et3N, DMAP / CH2Cl2 / 2.5 h / 25 °C 5: 95 percent / NaI / acetone / 15 h / Heating 6: 97 percent / acetonitrile / 45 h / Heating 7: n-BuLi / tetrahydrofuran; hexane / 1.) -78 deg C to -40 deg C, 2.) 20 deg C, 3 h 8: 1.) B2H6*THF, 2.) 3 N NaOH, 30percent H2O2 / 1.) THF, 15-20 deg C, 30 min, 2.) EtOH, 40 deg C, 30 min 9: 100 percent / i-Pr2NEt / CH2Cl2 / 1.) 25 deg C, 5 h, 2.) 40 deg C, 2.5 h 10: 99 percent / nBu4NF / tetrahydrofuran / 2.5 h / 25 °C 11: DMSO, (COCl)2 / CH2Cl2 / 0.5 h / -78 °C 12: t-BuOK / tetrahydrofuran / 1.) 25 deg C, 1.5 h, 2.) 55 deg C, 1 h 13: methanol / 2 h / 25 °C 14: NaBH4, AcOH / 2 h / 25 °C 15: 76 percent / Na, NH3 / tetrahydrofuran / 0.25 h / -78 °C 16: 96 percent / pyridine, DMAP / 0.5 h / 0 °C 17: 42 percent / KI, ZnCu / dimethylformamide / 4 h / Heating 18: aq. acetic acid / 0.5 h / 40 °C 19: Jones reagent / acetone / 1 h / 25 °C 20: 100 percent / 80percent aq. AcOH / 3 h / Heating View Scheme

1: NaH / dimethylformamide / 1.) 0 deg C, 30 min, 2.) 25 deg C, 1 h 2: 86 percent / H2 / PdCl2 / methanol / 0.33 h 3: 99 percent / Et3N, DMAP / CH2Cl2 / 2.5 h / 25 °C 4: 95 percent / NaI / acetone / 15 h / Heating 5: 97 percent / acetonitrile / 45 h / Heating 6: n-BuLi / tetrahydrofuran; hexane / 1.) -78 deg C to -40 deg C, 2.) 20 deg C, 3 h 7: 1.) B2H6*THF, 2.) 3 N NaOH, 30percent H2O2 / 1.) THF, 15-20 deg C, 30 min, 2.) EtOH, 40 deg C, 30 min 8: 100 percent / i-Pr2NEt / CH2Cl2 / 1.) 25 deg C, 5 h, 2.) 40 deg C, 2.5 h 9: 99 percent / nBu4NF / tetrahydrofuran / 2.5 h / 25 °C 10: DMSO, (COCl)2 / CH2Cl2 / 0.5 h / -78 °C 11: t-BuOK / tetrahydrofuran / 1.) 25 deg C, 1.5 h, 2.) 55 deg C, 1 h 12: methanol / 2 h / 25 °C 13: NaBH4, AcOH / 2 h / 25 °C 14: 76 percent / Na, NH3 / tetrahydrofuran / 0.25 h / -78 °C 15: 96 percent / pyridine, DMAP / 0.5 h / 0 °C 16: 42 percent / KI, ZnCu / dimethylformamide / 4 h / Heating 17: aq. acetic acid / 0.5 h / 40 °C 18: Jones reagent / acetone / 1 h / 25 °C 19: 100 percent / 80percent aq. AcOH / 3 h / Heating View Scheme

1: 86 percent / H2 / PdCl2 / methanol / 0.33 h 2: 99 percent / Et3N, DMAP / CH2Cl2 / 2.5 h / 25 °C 3: 95 percent / NaI / acetone / 15 h / Heating 4: 97 percent / acetonitrile / 45 h / Heating 5: n-BuLi / tetrahydrofuran; hexane / 1.) -78 deg C to -40 deg C, 2.) 20 deg C, 3 h 6: 1.) B2H6*THF, 2.) 3 N NaOH, 30percent H2O2 / 1.) THF, 15-20 deg C, 30 min, 2.) EtOH, 40 deg C, 30 min 7: 100 percent / i-Pr2NEt / CH2Cl2 / 1.) 25 deg C, 5 h, 2.) 40 deg C, 2.5 h 8: 99 percent / nBu4NF / tetrahydrofuran / 2.5 h / 25 °C 9: DMSO, (COCl)2 / CH2Cl2 / 0.5 h / -78 °C 10: t-BuOK / tetrahydrofuran / 1.) 25 deg C, 1.5 h, 2.) 55 deg C, 1 h 11: methanol / 2 h / 25 °C 12: NaBH4, AcOH / 2 h / 25 °C 13: 76 percent / Na, NH3 / tetrahydrofuran / 0.25 h / -78 °C 14: 96 percent / pyridine, DMAP / 0.5 h / 0 °C 15: 42 percent / KI, ZnCu / dimethylformamide / 4 h / Heating 16: aq. acetic acid / 0.5 h / 40 °C 17: Jones reagent / acetone / 1 h / 25 °C 18: 100 percent / 80percent aq. AcOH / 3 h / Heating View Scheme

1: 398 mg / BF3*Et2O / CH2Cl2 / 1 h / -90 °C 2: 76 mg / SmI2 / tetrahydrofuran; methanol / 14 h / -16 °C 3: 97 percent / NEt3; DMAP / CH2Cl2 / 14 h / 20 °C 4: 82 percent / DDQ / CH2Cl2; H2O / 0.25 h 5: TPAP; NMO; 4 Angstroem molecular sieves / CH2Cl2 / 0.42 h 6: 130 mg / diisopropylamine; n-BuLi / tetrahydrofuran; methyl acetate / 1 h / -78 - 20 °C 7: 86 percent / aq. HCl / methanol / 12 h / Heating View Scheme