1: 60 percent / FeCl3, Drierite / 3 h / 50 °C 2: 1.) aq. KOH, 2.) aq. KIO4 / 1.) 40 deg C, 15 min, 2.) 4 deg C, 5 h 3: pyridinium p-toluenesulfonate / 12 h / 60 °C 4: 1.) BuLi / 1.) THF, hexane, -78 deg C, 15 min, 2.) THF, hexane, -78 deg C (3 h), -> room temp. (1 h) View Scheme

1: pyridinium p-toluenesulfonate / 12 h / 60 °C 2: 1.) BuLi / 1.) THF, hexane, -78 deg C, 15 min, 2.) THF, hexane, -78 deg C (3 h), -> room temp. (1 h) View Scheme

n-butyllithium 1.) THF, hexane, - 78 deg C, 15 min, 2.) THF, hexane, - 78 deg, 2.5 h; Yield given. Multistep reaction;

1.1: tetrahydrofuran / 12 h / -78 - 20 °C 2.1: sodium periodate / methanol; water / 1 h / 0 - 20 °C 3.1: tetrahydrofuran / 0 °C 4.1: Grubb's 2nd generation catalyst / dichloromethane / 20 °C 5.1: Dess-Martin periodane; sodium hydrogencarbonate / dichloromethane / 2 h 5.2: 0.5 h View Scheme

n-butyllithium 1.) THF, hexane, -78 deg C, 30 mni, 2.) THF, hexane, a) -78 deg C, 2 h, b) from -78 deg C to RT, 45 min; Yield given. Multistep reaction;

1: 1.) aq. KOH, 2.) aq. KIO4 / 1.) 40 deg C, 15 min, 2.) 4 deg C, 5 h 2: pyridinium p-toluenesulfonate / 12 h / 60 °C 3: 1.) BuLi / 1.) THF, hexane, -78 deg C, 15 min, 2.) THF, hexane, -78 deg C (3 h), -> room temp. (1 h) View Scheme

2: CaCO3 / toluene / 15 h / Heating 3: 82 percent / DIBAH / CH2Cl2 / 4 h / -78 °C 4: 100 percent / triethylamine / CH2Cl2 / 0.75 h / 5 °C 5: 1) NaH, 18-crown-6 / 1) DMF, 60 deg C, 6 h, 2) DMF, 48 h, RT, then 65 deg C, 6 h 6: 72 percent / CF3COOH, H2O / 50 °C View Scheme

1: 81 percent / -78 - -30 °C 2: diisobutylaluminum hydride / CH2Cl2 / 3 h / 0 °C 3: 95 percent / pyridine / CH2Cl2 / 0.5 h / 0 °C 4: 30 percent / NaH, 18-crown-6 (3 equiv. each) / dimethylformamide / 18 h / 0 °C 5: 79 percent / trifluoroacetic acid / H2O / 3 h / 50 °C View Scheme