1: 98 percent / 2,6-lutidine / CH2Cl2 / 0.75 h / -78 °C 2: 1) O3, 2) PPh3 / 1) CH2Cl2, -78 deg C, 30 min, 2) Ch2Cl2, -78 deg C -> room temperature; room temperature, 1 h 3: lithium tri-tert-butoxyaluminohydride / tetrahydrofuran / 1) -78 deg C, 5 min, 2) 0 deg C, 15 min 4: 1.26 g / Et3N, 4-DMAP / CH2Cl2 / 1) 0 deg C, 2 h, 2) 25 deg C, 10 h 5: 1) LDA / 1) THF, -78 deg C, 15 min; -78 deg C -> -40 deg C, 1 h, 2) THF, -78 deg C, 15 min 6: 96 percent / 2,6-lutidine / CH2Cl2 / 2 h / 0 °C 7: 85 percent / camphorsulfonic acid / CH2Cl2; methanol / 0.5 h / 0 - 25 °C 8: 1) (COCl)2, DMSO, 2) Et3N / 1) CH2Cl2, -78 deg C, 30 min, 2) CH2Cl2, -78 deg C -> 0 deg C, 30 min 9: 90 percent / NaClO2, isobutylene, NaH2PO4 / 2-methyl-propan-2-ol; H2O; tetrahydrofuran / 1 h / Ambient temperature 10: 73 percent / TBAF / tetrahydrofuran / 8 h / 25 °C 11: 1) Et3N, 2,4,6-trichlorobenzoyl chloride, 2) 4-DMAP / 1) THF, 25 deg C, 15 min, 2) toluene, 25 deg C, 12 h 12: 91 percent / CF3CO2H / CH2Cl2 / 1) -20 deg C -> 0 deg C, 2) 0 deg C, 1 h View Scheme

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

1: 98 percent / Pb(OAc)4 / ethyl acetate / 0.25 h / 0 °C 2: 95 percent / benzene / 3 h / Heating 3: 98 percent / DIBAL / tetrahydrofuran; CH2Cl2 / 3 h / -78 °C 4: 83 percent / Ph3P, CCl4 / 24 h / 100 °C 5: 99 percent / LiEt3BH / tetrahydrofuran / 1 h / 0 °C 6: 91 percent / 9-BBN / tetrahydrofuran / 2 h / 0 °C 7: 92 percent / I2, imidazole, Ph3P / diethyl ether; acetonitrile / 0.5 h / 0 °C 8: 1) LDA / 1) THF, 0 deg C, 8 h, 2) THF, -100 deg C -> -20 deg C, 10 h 9: 80 percent / monoperoxyphthalic acid magnesium salt / methanol / 1 h / 0 °C 10: 82 percent / DIBAL / toluene / 1 h / -78 °C 11: 1) LDA / 1) THF, -78 deg C, 15 min; -78 deg C -> -40 deg C, 1 h, 2) THF, -78 deg C, 15 min 12: 96 percent / 2,6-lutidine / CH2Cl2 / 2 h / 0 °C 13: 85 percent / camphorsulfonic acid / CH2Cl2; methanol / 0.5 h / 0 - 25 °C 14: 1) (COCl)2, DMSO, 2) Et3N / 1) CH2Cl2, -78 deg C, 30 min, 2) CH2Cl2, -78 deg C -> 0 deg C, 30 min 15: 90 percent / NaClO2, isobutylene, NaH2PO4 / 2-methyl-propan-2-ol; H2O; tetrahydrofuran / 1 h / Ambient temperature 16: 73 percent / TBAF / tetrahydrofuran / 8 h / 25 °C 17: 1) Et3N, 2,4,6-trichlorobenzoyl chloride, 2) 4-DMAP / 1) THF, 25 deg C, 15 min, 2) toluene, 25 deg C, 12 h 18: 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 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: 91 percent / 9-BBN / tetrahydrofuran / 2 h / 0 °C 2: 92 percent / I2, imidazole, Ph3P / diethyl ether; acetonitrile / 0.5 h / 0 °C 3: 1) LDA / 1) THF, 0 deg C, 8 h, 2) THF, -100 deg C -> -20 deg C, 10 h 4: 80 percent / monoperoxyphthalic acid magnesium salt / methanol / 1 h / 0 °C 5: 82 percent / DIBAL / toluene / 1 h / -78 °C 6: 1) LDA / 1) THF, -78 deg C, 15 min; -78 deg C -> -40 deg C, 1 h, 2) THF, -78 deg C, 15 min 7: 96 percent / 2,6-lutidine / CH2Cl2 / 2 h / 0 °C 8: 85 percent / camphorsulfonic acid / CH2Cl2; methanol / 0.5 h / 0 - 25 °C 9: 1) (COCl)2, DMSO, 2) Et3N / 1) CH2Cl2, -78 deg C, 30 min, 2) CH2Cl2, -78 deg C -> 0 deg C, 30 min 10: 90 percent / NaClO2, isobutylene, NaH2PO4 / 2-methyl-propan-2-ol; H2O; tetrahydrofuran / 1 h / Ambient temperature 11: 73 percent / TBAF / tetrahydrofuran / 8 h / 25 °C 12: 1) Et3N, 2,4,6-trichlorobenzoyl chloride, 2) 4-DMAP / 1) THF, 25 deg C, 15 min, 2) toluene, 25 deg C, 12 h 13: 91 percent / CF3CO2H / CH2Cl2 / 1) -20 deg C -> 0 deg C, 2) 0 deg C, 1 h View Scheme

1: 92 percent / I2, imidazole, Ph3P / diethyl ether; acetonitrile / 0.5 h / 0 °C 2: 1) LDA / 1) THF, 0 deg C, 8 h, 2) THF, -100 deg C -> -20 deg C, 10 h 3: 80 percent / monoperoxyphthalic acid magnesium salt / methanol / 1 h / 0 °C 4: 82 percent / DIBAL / toluene / 1 h / -78 °C 5: 1) LDA / 1) THF, -78 deg C, 15 min; -78 deg C -> -40 deg C, 1 h, 2) THF, -78 deg C, 15 min 6: 96 percent / 2,6-lutidine / CH2Cl2 / 2 h / 0 °C 7: 85 percent / camphorsulfonic acid / CH2Cl2; methanol / 0.5 h / 0 - 25 °C 8: 1) (COCl)2, DMSO, 2) Et3N / 1) CH2Cl2, -78 deg C, 30 min, 2) CH2Cl2, -78 deg C -> 0 deg C, 30 min 9: 90 percent / NaClO2, isobutylene, NaH2PO4 / 2-methyl-propan-2-ol; H2O; tetrahydrofuran / 1 h / Ambient temperature 10: 73 percent / TBAF / tetrahydrofuran / 8 h / 25 °C 11: 1) Et3N, 2,4,6-trichlorobenzoyl chloride, 2) 4-DMAP / 1) THF, 25 deg C, 15 min, 2) toluene, 25 deg C, 12 h 12: 91 percent / CF3CO2H / CH2Cl2 / 1) -20 deg C -> 0 deg C, 2) 0 deg C, 1 h View Scheme

1: 1) LDA / 1) THF, 0 deg C, 8 h, 2) THF, -100 deg C -> -20 deg C, 10 h 2: 80 percent / monoperoxyphthalic acid magnesium salt / methanol / 1 h / 0 °C 3: 82 percent / DIBAL / toluene / 1 h / -78 °C 4: 1) LDA / 1) THF, -78 deg C, 15 min; -78 deg C -> -40 deg C, 1 h, 2) THF, -78 deg C, 15 min 5: 96 percent / 2,6-lutidine / CH2Cl2 / 2 h / 0 °C 6: 85 percent / camphorsulfonic acid / CH2Cl2; methanol / 0.5 h / 0 - 25 °C 7: 1) (COCl)2, DMSO, 2) Et3N / 1) CH2Cl2, -78 deg C, 30 min, 2) CH2Cl2, -78 deg C -> 0 deg C, 30 min 8: 90 percent / NaClO2, isobutylene, NaH2PO4 / 2-methyl-propan-2-ol; H2O; tetrahydrofuran / 1 h / Ambient temperature 9: 73 percent / TBAF / tetrahydrofuran / 8 h / 25 °C 10: 1) Et3N, 2,4,6-trichlorobenzoyl chloride, 2) 4-DMAP / 1) THF, 25 deg C, 15 min, 2) toluene, 25 deg C, 12 h 11: 91 percent / CF3CO2H / CH2Cl2 / 1) -20 deg C -> 0 deg C, 2) 0 deg C, 1 h View Scheme

1: 83 percent / Ph3P, CCl4 / 24 h / 100 °C 2: 99 percent / LiEt3BH / tetrahydrofuran / 1 h / 0 °C 3: 91 percent / 9-BBN / tetrahydrofuran / 2 h / 0 °C 4: 92 percent / I2, imidazole, Ph3P / diethyl ether; acetonitrile / 0.5 h / 0 °C 5: 1) LDA / 1) THF, 0 deg C, 8 h, 2) THF, -100 deg C -> -20 deg C, 10 h 6: 80 percent / monoperoxyphthalic acid magnesium salt / methanol / 1 h / 0 °C 7: 82 percent / DIBAL / toluene / 1 h / -78 °C 8: 1) LDA / 1) THF, -78 deg C, 15 min; -78 deg C -> -40 deg C, 1 h, 2) THF, -78 deg C, 15 min 9: 96 percent / 2,6-lutidine / CH2Cl2 / 2 h / 0 °C 10: 85 percent / camphorsulfonic acid / CH2Cl2; methanol / 0.5 h / 0 - 25 °C 11: 1) (COCl)2, DMSO, 2) Et3N / 1) CH2Cl2, -78 deg C, 30 min, 2) CH2Cl2, -78 deg C -> 0 deg C, 30 min 12: 90 percent / NaClO2, isobutylene, NaH2PO4 / 2-methyl-propan-2-ol; H2O; tetrahydrofuran / 1 h / Ambient temperature 13: 73 percent / TBAF / tetrahydrofuran / 8 h / 25 °C 14: 1) Et3N, 2,4,6-trichlorobenzoyl chloride, 2) 4-DMAP / 1) THF, 25 deg C, 15 min, 2) toluene, 25 deg C, 12 h 15: 91 percent / CF3CO2H / CH2Cl2 / 1) -20 deg C -> 0 deg C, 2) 0 deg C, 1 h View Scheme

1: 99 percent / LiEt3BH / tetrahydrofuran / 1 h / 0 °C 2: 91 percent / 9-BBN / tetrahydrofuran / 2 h / 0 °C 3: 92 percent / I2, imidazole, Ph3P / diethyl ether; acetonitrile / 0.5 h / 0 °C 4: 1) LDA / 1) THF, 0 deg C, 8 h, 2) THF, -100 deg C -> -20 deg C, 10 h 5: 80 percent / monoperoxyphthalic acid magnesium salt / methanol / 1 h / 0 °C 6: 82 percent / DIBAL / toluene / 1 h / -78 °C 7: 1) LDA / 1) THF, -78 deg C, 15 min; -78 deg C -> -40 deg C, 1 h, 2) THF, -78 deg C, 15 min 8: 96 percent / 2,6-lutidine / CH2Cl2 / 2 h / 0 °C 9: 85 percent / camphorsulfonic acid / CH2Cl2; methanol / 0.5 h / 0 - 25 °C 10: 1) (COCl)2, DMSO, 2) Et3N / 1) CH2Cl2, -78 deg C, 30 min, 2) CH2Cl2, -78 deg C -> 0 deg C, 30 min 11: 90 percent / NaClO2, isobutylene, NaH2PO4 / 2-methyl-propan-2-ol; H2O; tetrahydrofuran / 1 h / Ambient temperature 12: 73 percent / TBAF / tetrahydrofuran / 8 h / 25 °C 13: 1) Et3N, 2,4,6-trichlorobenzoyl chloride, 2) 4-DMAP / 1) THF, 25 deg C, 15 min, 2) toluene, 25 deg C, 12 h 14: 91 percent / CF3CO2H / CH2Cl2 / 1) -20 deg C -> 0 deg C, 2) 0 deg C, 1 h View Scheme

1: 98 percent / DIBAL / tetrahydrofuran; CH2Cl2 / 3 h / -78 °C 2: 83 percent / Ph3P, CCl4 / 24 h / 100 °C 3: 99 percent / LiEt3BH / tetrahydrofuran / 1 h / 0 °C 4: 91 percent / 9-BBN / tetrahydrofuran / 2 h / 0 °C 5: 92 percent / I2, imidazole, Ph3P / diethyl ether; acetonitrile / 0.5 h / 0 °C 6: 1) LDA / 1) THF, 0 deg C, 8 h, 2) THF, -100 deg C -> -20 deg C, 10 h 7: 80 percent / monoperoxyphthalic acid magnesium salt / methanol / 1 h / 0 °C 8: 82 percent / DIBAL / toluene / 1 h / -78 °C 9: 1) LDA / 1) THF, -78 deg C, 15 min; -78 deg C -> -40 deg C, 1 h, 2) THF, -78 deg C, 15 min 10: 96 percent / 2,6-lutidine / CH2Cl2 / 2 h / 0 °C 11: 85 percent / camphorsulfonic acid / CH2Cl2; methanol / 0.5 h / 0 - 25 °C 12: 1) (COCl)2, DMSO, 2) Et3N / 1) CH2Cl2, -78 deg C, 30 min, 2) CH2Cl2, -78 deg C -> 0 deg C, 30 min 13: 90 percent / NaClO2, isobutylene, NaH2PO4 / 2-methyl-propan-2-ol; H2O; tetrahydrofuran / 1 h / Ambient temperature 14: 73 percent / TBAF / tetrahydrofuran / 8 h / 25 °C 15: 1) Et3N, 2,4,6-trichlorobenzoyl chloride, 2) 4-DMAP / 1) THF, 25 deg C, 15 min, 2) toluene, 25 deg C, 12 h 16: 91 percent / CF3CO2H / CH2Cl2 / 1) -20 deg C -> 0 deg C, 2) 0 deg C, 1 h View Scheme