1: 49 percent / SOCl2, pyridine / 3 h / 15 °C 2: 92 percent / MnO2 / hexane / 12 h / 15 °C 3: 65 percent / 67 percent aq. Ca(ClO)2, glacial acetic acid / acetonitrile / 20 h / 15 °C View Scheme

1: 49 percent / SOCl2, pyridine / 3 h / 15 °C 2: 92 percent / MnO2 / hexane / 12 h / 15 °C View Scheme

1: dimethylformamide / 24 h / Ambient temperature 2: 78 percent / SeO2, t-BuOOH / CH2Cl2 / 25 h / 20 °C 3: 1.) Ti(OiPr)4, CaH2, 4A molecular sieves, D-(-)-DET, 2.) tert-BuOOH / 1.) CH2Cl2, -20 deg C, 15 min, 2.) CH2Cl2, toluene, -40 deg C, 5 h 4: 1.) LDA / 1.) THF, hexane, -78 deg C, 40 min, 2.) THF, hexane, from -78 deg C to RT, 2 h 5: 78 percent / Li, EtNH2 / tetrahydrofuran / 4 h / -78 °C 6: 1.) Ph3P, N-chlorosuccinimide / 1.) THF, 20 deg C, 5 h, 2.) THF, 3 h 7: 98 percent / imidazole / dimethylformamide / 10 h / 50 °C 8: LDA, DABCO / tetrahydrofuran; hexane / 48 h / -78 °C 9: Bu4N+F- / tetrahydrofuran / 24 h / 15 °C 10: 70 percent / Li, EtNH2 / tetrahydrofuran / 3.5 h / -78 °C View Scheme

1: PBr3 / diethyl ether / 3 h / 20 °C 2: dimethylformamide / 24 h / Ambient temperature 3: 78 percent / SeO2, t-BuOOH / CH2Cl2 / 25 h / 20 °C 4: 1.) Ti(OiPr)4, CaH2, 4A molecular sieves, D-(-)-DET, 2.) tert-BuOOH / 1.) CH2Cl2, -20 deg C, 15 min, 2.) CH2Cl2, toluene, -40 deg C, 5 h 5: 1.) LDA / 1.) THF, hexane, -78 deg C, 40 min, 2.) THF, hexane, from -78 deg C to RT, 2 h 6: 78 percent / Li, EtNH2 / tetrahydrofuran / 4 h / -78 °C 7: 1.) Ph3P, N-chlorosuccinimide / 1.) THF, 20 deg C, 5 h, 2.) THF, 3 h 8: 98 percent / imidazole / dimethylformamide / 10 h / 50 °C 9: LDA, DABCO / tetrahydrofuran; hexane / 48 h / -78 °C 10: Bu4N+F- / tetrahydrofuran / 24 h / 15 °C 11: 70 percent / Li, EtNH2 / tetrahydrofuran / 3.5 h / -78 °C View Scheme

1: 73 percent / SeO2, t-BuOOH / CH2Cl2 / 15 h / 20 °C 2: 85 percent / Ph3P, N-chlorosuccinimide / tetrahydrofuran / 5 h / 20 °C 3: 1.) LDA / 1.) THF, hexane, -78 deg C, 40 min, 2.) THF, hexane, from -78 deg C to RT, 2 h 4: 78 percent / Li, EtNH2 / tetrahydrofuran / 4 h / -78 °C 5: 1.) Ph3P, N-chlorosuccinimide / 1.) THF, 20 deg C, 5 h, 2.) THF, 3 h 6: 98 percent / imidazole / dimethylformamide / 10 h / 50 °C 7: LDA, DABCO / tetrahydrofuran; hexane / 48 h / -78 °C 8: Bu4N+F- / tetrahydrofuran / 24 h / 15 °C 9: 70 percent / Li, EtNH2 / tetrahydrofuran / 3.5 h / -78 °C View Scheme

1: 85 percent / Ph3P, N-chlorosuccinimide / tetrahydrofuran / 5 h / 20 °C 2: 1.) LDA / 1.) THF, hexane, -78 deg C, 40 min, 2.) THF, hexane, from -78 deg C to RT, 2 h 3: 78 percent / Li, EtNH2 / tetrahydrofuran / 4 h / -78 °C 4: 1.) Ph3P, N-chlorosuccinimide / 1.) THF, 20 deg C, 5 h, 2.) THF, 3 h 5: 98 percent / imidazole / dimethylformamide / 10 h / 50 °C 6: LDA, DABCO / tetrahydrofuran; hexane / 48 h / -78 °C 7: Bu4N+F- / tetrahydrofuran / 24 h / 15 °C 8: 70 percent / Li, EtNH2 / tetrahydrofuran / 3.5 h / -78 °C View Scheme

1: 78 percent / SeO2, t-BuOOH / CH2Cl2 / 25 h / 20 °C 2: 1.) Ti(OiPr)4, CaH2, 4A molecular sieves, D-(-)-DET, 2.) tert-BuOOH / 1.) CH2Cl2, -20 deg C, 15 min, 2.) CH2Cl2, toluene, -40 deg C, 5 h 3: 1.) LDA / 1.) THF, hexane, -78 deg C, 40 min, 2.) THF, hexane, from -78 deg C to RT, 2 h 4: 78 percent / Li, EtNH2 / tetrahydrofuran / 4 h / -78 °C 5: 1.) Ph3P, N-chlorosuccinimide / 1.) THF, 20 deg C, 5 h, 2.) THF, 3 h 6: 98 percent / imidazole / dimethylformamide / 10 h / 50 °C 7: LDA, DABCO / tetrahydrofuran; hexane / 48 h / -78 °C 8: Bu4N+F- / tetrahydrofuran / 24 h / 15 °C 9: 70 percent / Li, EtNH2 / tetrahydrofuran / 3.5 h / -78 °C View Scheme

1: 1.) LDA / 1.) THF, hexane, -78 deg C, 40 min, 2.) THF, hexane, from -78 deg C to RT, 2 h 2: 78 percent / Li, EtNH2 / tetrahydrofuran / 4 h / -78 °C 3: 1.) Ph3P, N-chlorosuccinimide / 1.) THF, 20 deg C, 5 h, 2.) THF, 3 h 4: 98 percent / imidazole / dimethylformamide / 10 h / 50 °C 5: LDA, DABCO / tetrahydrofuran; hexane / 48 h / -78 °C 6: Bu4N+F- / tetrahydrofuran / 24 h / 15 °C 7: 70 percent / Li, EtNH2 / tetrahydrofuran / 3.5 h / -78 °C View Scheme

1: 1.) Ph3P, N-chlorosuccinimide / 1.) THF, 20 deg C, 5 h, 2.) THF, 3 h 2: 98 percent / imidazole / dimethylformamide / 10 h / 50 °C 3: LDA, DABCO / tetrahydrofuran; hexane / 48 h / -78 °C 4: Bu4N+F- / tetrahydrofuran / 24 h / 15 °C 5: 70 percent / Li, EtNH2 / tetrahydrofuran / 3.5 h / -78 °C View Scheme

1: LDA, DABCO / tetrahydrofuran; hexane / 48 h / -78 °C 2: Bu4N+F- / tetrahydrofuran / 24 h / 15 °C 3: 70 percent / Li, EtNH2 / tetrahydrofuran / 3.5 h / -78 °C View Scheme