1: 86 percent / pyridine, N,N-dimethylaminopyridine (DMAP) / CH2Cl2 / 1) -78 deg C, 1 h, 2) to 0 deg C, 12 h 2: 71 percent / triethylamine, 1,8-diazabicyclo<5.4.0>undec-7-ene (DBU) / CH2Cl2 / 6 h / 0 °C 3: 75 percent / diisobutylaluminium hydride (DIBAL-H) / tetrahydrofuran / 1 h / 0 °C 4: 95 percent / pyridine, N,N-dimethylaminopyridine (DMAP) / CH2Cl2 / 12 h / Ambient temperature 5: 80 percent / pyridinium chlorochromate, 3 Angstroem molecular sieves / CH2Cl2 / 12 h / Ambient temperature 6: 100 percent / 50percent aq. CF3COOH / 4 h / Ambient temperature View Scheme

1: NBS*H2O 2: 65 percent / DIBAL-H / benzene; toluene 3: 87 percent / LiN(TMS)2 / tetrahydrofuran / -78 °C 4: 93 percent / BF3*OEt2 / dimethylsulfoxide 5: 71 percent / CH3SO3H / dimethylsulfoxide / 1.5 h / 20 °C 6: 54 percent / DCC; DMAP / tetrahydrofuran 7: 73 percent / TFA; water View Scheme

1: 93 percent / BF3*OEt2 / dimethylsulfoxide 2: 71 percent / CH3SO3H / dimethylsulfoxide / 1.5 h / 20 °C 3: 54 percent / DCC; DMAP / tetrahydrofuran 4: 73 percent / TFA; water View Scheme

1: 54 percent / DCC; DMAP / tetrahydrofuran 2: 73 percent / TFA; water View Scheme

1: 87 percent / LiN(TMS)2 / tetrahydrofuran / -78 °C 2: 93 percent / BF3*OEt2 / dimethylsulfoxide 3: 71 percent / CH3SO3H / dimethylsulfoxide / 1.5 h / 20 °C 4: 54 percent / DCC; DMAP / tetrahydrofuran 5: 73 percent / TFA; water View Scheme

1: 71 percent / CH3SO3H / dimethylsulfoxide / 1.5 h / 20 °C 2: 54 percent / DCC; DMAP / tetrahydrofuran 3: 73 percent / TFA; water View Scheme

1: 65 percent / DIBAL-H / benzene; toluene 2: 87 percent / LiN(TMS)2 / tetrahydrofuran / -78 °C 3: 93 percent / BF3*OEt2 / dimethylsulfoxide 4: 71 percent / CH3SO3H / dimethylsulfoxide / 1.5 h / 20 °C 5: 54 percent / DCC; DMAP / tetrahydrofuran 6: 73 percent / TFA; water View Scheme

1: cesium acetate / dimethylformamide 2: NBS*H2O 3: 65 percent / DIBAL-H / benzene; toluene 4: 87 percent / LiN(TMS)2 / tetrahydrofuran / -78 °C 5: 93 percent / BF3*OEt2 / dimethylsulfoxide 6: 71 percent / CH3SO3H / dimethylsulfoxide / 1.5 h / 20 °C 7: 54 percent / DCC; DMAP / tetrahydrofuran 8: 73 percent / TFA; water View Scheme

1: 86 percent / 90percent TFA 2: 71 percent / BF3*Et2O / acetonitrile View Scheme

1: 2) Dowex 50WX8 (H+) / 1) DMF, benzene, reflux, 3 h, 2) reflux, 24 h 2: 96 percent / methanol / 1 h / 0 °C 3: 1) oxalyl chloride, DMSO, 2) triethylamine / 1) CH2Cl2, 40 min, -60 deg C, 2) 10 min, -60 deg C 4: POCl3, pyridine / Ambient temperature 5: 82 percent / NaBH4 / methanol / 1.5 h / 0 °C 6: 82 percent / OsO4, trimethylamine-N-oxide, pyridine, water / 2-methyl-propan-2-ol / 12 h / Heating 7: 100 percent / pyridine, N,N-dimethylaminopyridine (DMAP) / CH2Cl2 / 12 h / Ambient temperature 8: 86 percent / pyridine, N,N-dimethylaminopyridine (DMAP) / CH2Cl2 / 1) -78 deg C, 1 h, 2) to 0 deg C, 12 h 9: 71 percent / triethylamine, 1,8-diazabicyclo<5.4.0>undec-7-ene (DBU) / CH2Cl2 / 6 h / 0 °C 10: 75 percent / diisobutylaluminium hydride (DIBAL-H) / tetrahydrofuran / 1 h / 0 °C 11: 95 percent / pyridine, N,N-dimethylaminopyridine (DMAP) / CH2Cl2 / 12 h / Ambient temperature 12: 80 percent / pyridinium chlorochromate, 3 Angstroem molecular sieves / CH2Cl2 / 12 h / Ambient temperature 13: 100 percent / 50percent aq. CF3COOH / 4 h / Ambient temperature View Scheme