1: 1.26 g / Et3N, 4-DMAP / CH2Cl2 / 1) 0 deg C, 2 h, 2) 25 deg C, 10 h 2: 1) LDA / 1) THF, -78 deg C, 15 min; -78 deg C -> -40 deg C, 1 h, 2) THF, -78 deg C, 15 min 3: 96 percent / 2,6-lutidine / CH2Cl2 / 2 h / 0 °C 4: 85 percent / camphorsulfonic acid / CH2Cl2; methanol / 0.5 h / 0 - 25 °C View Scheme

1: 1.26 g / Et3N, 4-DMAP / CH2Cl2 / 1) 0 deg C, 2 h, 2) 25 deg C, 10 h 2: 1) LDA / 1) THF, -78 deg C, 15 min; -78 deg C -> -40 deg C, 1 h, 2) THF, -78 deg C, 15 min 3: 96 percent / 2,6-lutidine / CH2Cl2 / 2 h / 0 °C 4: 85 percent / camphorsulfonic acid / CH2Cl2; methanol / 0.5 h / 0 - 25 °C 5: 1) (COCl)2, DMSO, 2) Et3N / 1) CH2Cl2, -78 deg C, 30 min, 2) CH2Cl2, -78 deg C -> 0 deg C, 30 min 6: 90 percent / NaClO2, isobutylene, NaH2PO4 / 2-methyl-propan-2-ol; H2O; tetrahydrofuran / 1 h / Ambient temperature 7: 73 percent / TBAF / tetrahydrofuran / 8 h / 25 °C 8: 1) Et3N, 2,4,6-trichlorobenzoyl chloride, 2) 4-DMAP / 1) THF, 25 deg C, 15 min, 2) toluene, 25 deg C, 12 h 9: 91 percent / CF3CO2H / CH2Cl2 / 1) -20 deg C -> 0 deg C, 2) 0 deg C, 1 h 10: Na2EDTA, 1,1,1-trifluoroacetone, Oxone, NaHCO3 / acetonitrile; H2O / 0 °C View Scheme

1: 1.26 g / Et3N, 4-DMAP / CH2Cl2 / 1) 0 deg C, 2 h, 2) 25 deg C, 10 h 2: 1) LDA / 1) THF, -78 deg C, 15 min; -78 deg C -> -40 deg C, 1 h, 2) THF, -78 deg C, 15 min 3: 96 percent / 2,6-lutidine / CH2Cl2 / 2 h / 0 °C 4: 85 percent / camphorsulfonic acid / CH2Cl2; methanol / 0.5 h / 0 - 25 °C 5: 1) (COCl)2, DMSO, 2) Et3N / 1) CH2Cl2, -78 deg C, 30 min, 2) CH2Cl2, -78 deg C -> 0 deg C, 30 min 6: 90 percent / NaClO2, isobutylene, NaH2PO4 / 2-methyl-propan-2-ol; H2O; tetrahydrofuran / 1 h / Ambient temperature 7: 73 percent / TBAF / tetrahydrofuran / 8 h / 25 °C 8: 1) Et3N, 2,4,6-trichlorobenzoyl chloride, 2) 4-DMAP / 1) THF, 25 deg C, 15 min, 2) toluene, 25 deg C, 12 h 9: 91 percent / CF3CO2H / CH2Cl2 / 1) -20 deg C -> 0 deg C, 2) 0 deg C, 1 h View Scheme

1: 1.26 g / Et3N, 4-DMAP / CH2Cl2 / 1) 0 deg C, 2 h, 2) 25 deg C, 10 h 2: 1) LDA / 1) THF, -78 deg C, 15 min; -78 deg C -> -40 deg C, 1 h, 2) THF, -78 deg C, 15 min 3: 96 percent / 2,6-lutidine / CH2Cl2 / 2 h / 0 °C View Scheme

1: 1.26 g / Et3N, 4-DMAP / CH2Cl2 / 1) 0 deg C, 2 h, 2) 25 deg C, 10 h 2: 1) LDA / 1) THF, -78 deg C, 15 min; -78 deg C -> -40 deg C, 1 h, 2) THF, -78 deg C, 15 min 3: 96 percent / 2,6-lutidine / CH2Cl2 / 2 h / 0 °C 4: 85 percent / camphorsulfonic acid / CH2Cl2; methanol / 0.5 h / 0 - 25 °C 5: 1) (COCl)2, DMSO, 2) Et3N / 1) CH2Cl2, -78 deg C, 30 min, 2) CH2Cl2, -78 deg C -> 0 deg C, 30 min 6: 90 percent / NaClO2, isobutylene, NaH2PO4 / 2-methyl-propan-2-ol; H2O; tetrahydrofuran / 1 h / Ambient temperature View Scheme

1: 1.26 g / Et3N, 4-DMAP / CH2Cl2 / 1) 0 deg C, 2 h, 2) 25 deg C, 10 h 2: 1) LDA / 1) THF, -78 deg C, 15 min; -78 deg C -> -40 deg C, 1 h, 2) THF, -78 deg C, 15 min View Scheme

1.1: 1H-imidazole / dichloromethane / 14 h / 22 °C / |Inert atmosphere 2.1: diisopropylamine; n-butyllithium / tetrahydrofuran; hexane / 1.5 h / -78 - 0 °C / |Inert atmosphere 2.2: 0.25 h / -78 °C / |Inert atmosphere 3.1: 2,6-dimethylpyridine / tetrahydrofuran / 0.5 h / -50 °C / |Inert atmosphere 4.1: oxalyl dichloride / dichloromethane; dimethyl sulfoxide / 1 h / -78 - -40 °C / |Inert atmosphere 4.2: 0 - 22 °C / |Inert atmosphere 5.1: sodium dihydrogen phosphate monohydrate; 2-methyl-but-2-ene; sodium chlorite / water; tert-butyl alcohol / 3 h / 22 °C / |Inert atmosphere 6.1: 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; 4-(N,N-dimethlyamino)pyridine / dichloromethane / 16 h / 22 °C / |Inert atmosphere 7.1: C52H67Cl2NOW / benzene; toluene / 2.5 h / 22 °C / 1 Torr / |Inert atmosphere; |Glovebox 8.1: pyridine hydrogenfluoride / tetrahydrofuran / 36 h / 22 °C / |Inert atmosphere View Scheme

1H-imidazole in dichloromethane T=0 - 20°C; 16 h;

1H-imidazole in dichloromethane T=0°C; 3 h;