1.1: cerium(III) chloride / tetrahydrofuran / 0 - 5 °C 2.1: 4-(N,N-dimethlyamino)pyridine; triethylamine / dichloromethane / 0 - 5 °C 3.1: toluene-4-sulfonic acid / dichloromethane / 25 - 30 °C 4.1: water; sodium hydroxide / tetrahydrofuran; methanol / 2 h / 25 - 30 °C 5.1: hydrogenchloride / water / 25 - 30 °C / pH 6.5 - 7 6.1: N-ethyl-N,N-diisopropylamine / dichloromethane / 25 - 30 °C 6.2: 1.5 h / 0 - 5 °C 7.1: n-butyllithium / tetrahydrofuran; hexane / -15 - 0 °C / Inert atmosphere 7.2: 19 h / -5 - 2 °C / Inert atmosphere 8.1: ethyl acetate / 15 h / 25 - 30 °C / Inert atmosphere 9.1: sulfuric acid; water / 2 h / 0 - 10 °C / Inert atmosphere 10.1: ethyl acetate / 18 h / 25 - 30 °C / Inert atmosphere 11.1: acetic acid / dichloromethane; water / 0.5 h / pH 3.5 - 4 11.2: 0.5 h / 25 - 30 °C View Scheme

1.1: cerium(III) chloride / tetrahydrofuran / 0 - 5 °C 2.1: 4-(N,N-dimethlyamino)pyridine; triethylamine / dichloromethane / 0 - 5 °C 3.1: toluene-4-sulfonic acid / dichloromethane / 25 - 30 °C 4.1: water; sodium hydroxide / tetrahydrofuran; methanol / 25 - 30 °C 5.1: hydrogenchloride / water; ethyl acetate / 25 - 30 °C 6.1: N-ethyl-N,N-diisopropylamine / dichloromethane / 25 - 30 °C 6.2: 1 h / 0 - 5 °C 7.1: sodium methylate / methanol; N,N-dimethyl-formamide / 0 - 5 °C 8.1: ethyl acetate / 25 - 30 °C 9.1: sulfuric acid; water / 5 - 10 °C View Scheme

1: 99 percent / Et3N, 4-DMAP / CH2Cl2 / 0.25 h 2: 69 percent / NBS, (BzO)2 / CCl4 / 3 h / Heating 3: 1 N LiOH / tetrahydrofuran; methanol / 24 h / 23 °C View Scheme

1.1: cerium(III) chloride / tetrahydrofuran / 0 - 5 °C 2.1: 4-(N,N-dimethlyamino)pyridine; triethylamine / dichloromethane / 0 - 5 °C 3.1: toluene-4-sulfonic acid / dichloromethane / 25 - 30 °C 4.1: water; sodium hydroxide / tetrahydrofuran; methanol / 25 - 30 °C 5.1: hydrogenchloride / water; ethyl acetate / 25 - 30 °C 6.1: N-ethyl-N,N-diisopropylamine / dichloromethane / 25 - 30 °C 6.2: 1 h / 0 - 5 °C 7.1: sodium methylate / methanol; N,N-dimethyl-formamide / 0 - 5 °C 8.1: ethyl acetate / 25 - 30 °C 9.1: sulfuric acid; water / 5 - 10 °C 10.1: ethyl acetate / 25 - 30 °C 11.1: acetic acid / dichloromethane; water / 25 - 30 °C 11.2: 25 - 30 °C View Scheme

1: 99 percent / Et3N, 4-DMAP / CH2Cl2 / 0.25 h 2: 69 percent / NBS, (BzO)2 / CCl4 / 3 h / Heating View Scheme

1.1: cerium(III) chloride / tetrahydrofuran / 0 - 5 °C 2.1: 4-(N,N-dimethlyamino)pyridine; triethylamine / dichloromethane / 0 - 5 °C 3.1: toluene-4-sulfonic acid / dichloromethane / 25 - 30 °C 4.1: water; sodium hydroxide / tetrahydrofuran; methanol / 25 - 30 °C 5.1: hydrogenchloride / water; ethyl acetate / 25 - 30 °C 6.1: N-ethyl-N,N-diisopropylamine / dichloromethane / 25 - 30 °C 6.2: 1 h / 0 - 5 °C 7.1: sodium methylate / methanol; N,N-dimethyl-formamide / 0 - 5 °C 8.1: ethyl acetate / 25 - 30 °C 9.1: sodium methylate / methanol; N,N-dimethyl-formamide / 26 h / 25 - 45 °C 10.1: sulfuric acid; water / 2.5 h / 0 - 10 °C / Inert atmosphere View Scheme

1.1: N-ethyl-N,N-diisopropylamine / dichloromethane / 3 h / 0 - 5 °C 2.1: sodium methylate / methanol; N,N-dimethyl-formamide / 1.5 h / -5 - 0 °C 2.2: 19 h / 0 - 5 °C 3.1: tetrahydrofuran / 9 h / 0 - 5 °C View Scheme