1: 10 percent perchloric acid / tetrahydrofuran / 24 h / 0 °C 2: lead tetraacetate / CH2Cl2 / 1.) -20 deg C, 15 min, 2.) from -20 to 0 deg C, 15 min 3: hexamethylphosphoric acid triamide / 1.) -78 deg C, 30 min; 2.) from -78 deg C to 0 deg C, 90 min 4: 2.) lithium aluminum hydride / 1.) tosylation; View Scheme

1: 10 percent perchloric acid / tetrahydrofuran / 24 h / 0 °C 2: lead tetraacetate / CH2Cl2 / 1.) -20 deg C, 15 min, 2.) from -20 to 0 deg C, 15 min 3: hexamethylphosphoric acid triamide / 1.) -78 deg C, 30 min; 2.) from -78 deg C to 0 deg C, 90 min 4: saponification View Scheme

1: 0.5M HClO4 / tetrahydrofuran / 23 °C 2: Pb(OAc)4 / CH2Cl2 3: NaBH4, cyclopentene / ethanol; tetrahydrofuran / 0.5 h / -40 °C 4: 1) I2,imidazole, Ph3P, 2) aq.H2O2 / 1) benzene-acetonitrile at 23 deg C for 15 min 5: 99 percent / acetonitrile / 40 h / 60 °C 6: 1) potassium hexamethyldisilazide / 1) THF, -20 deg C, 5 min, 2) -78 deg C (30 min) to 23 deg C over 2 h 7: 1N aq.LiOH / 1,2-dimethoxy-ethane / 3 h / 23 °C View Scheme

1: 1.) KBr, 2.) t-BuOOH, vanadyl acetylacetonate / 1.) AcOH-H2O-THF, 5 deg C, 12 h, 2.) benzene, 23 deg C, 130 min 2: K2CO3 / methanol 3: saponification 4: MICA 5: potassium selenocyanate / methanol / Heating View Scheme

1: 1.) KBr, 2.) t-BuOOH, vanadyl acetylacetonate / 1.) AcOH-H2O-THF, 5 deg C, 12 h, 2.) benzene, 23 deg C, 130 min 2: 1.) trifluorometanesulphonic anhydride - pyridine, 2.) hexamethylphosphorous triamide / 1.) CH2Cl2, 0 deg C, 40 min, 2.) 0 deg C, 30 min View Scheme

1: 65 percent / aq. HClO4 / diethyl ether / 6 h / 20 °C 2: 64 percent / Pb(OAc)4 / CH2Cl2 / 0.5 h / -30 °C View Scheme

1: 10 percent perchloric acid / tetrahydrofuran / 24 h / 0 °C 2: lead tetraacetate / CH2Cl2 / 1.) -20 deg C, 15 min, 2.) from -20 to 0 deg C, 15 min 3: hexamethylphosphoric acid triamide / 1.) -78 deg C, 30 min; 2.) from -78 deg C to 0 deg C, 90 min 4: 1.) Jones oxidation, 0 deg C; 2.) saponification View Scheme