1: 100 percent / DIBAL / CH2Cl2 / 4 h / 0 °C 2: Ti(O-i-Pr)4, (-)-DET, TBHP / CH2Cl2 / 15 h / -20 °C 3: 0.5 N NaOH / H2O; 2-methyl-propan-2-ol / 15 h / 70 °C 4: Dowex 50X8-200 resin / H2O / 3 h / 25 °C View Scheme

1: 100 percent / DIBAL / CH2Cl2 / 4 h / 0 °C 2: Ti(O-i-Pr)4, (+)-DET, TBHP / CH2Cl2 / 15 h / -20 °C 3: 0.5 N NaOH / H2O; 2-methyl-propan-2-ol / 15 h / 70 °C 4: Dowex 50X8-200 resin / H2O / 3 h / 25 °C View Scheme

1: 100 percent / DIBAL / CH2Cl2 / 4 h / 0 °C 2: Ti(O-i-Pr)4, (+)-DET, TBHP / CH2Cl2 / 15 h / -20 °C 3: 0.5 N NaOH / H2O; 2-methyl-propan-2-ol / 15 h / 70 °C 4: Dowex 50X8-200 resin / H2O / 3 h / 25 °C View Scheme

1: 79 percent / sodium methylsulfinyl carbanion / dimethylsulfoxide / 10 °C 3: 94 percent / imidazole / dimethylformamide / 4 h / 25 °C 4: 1.) n-butyllithium, 2.) Gilman reagent, cuprrous cyanide, HMPA 5: H2, triethylamine / Lindlar catalyst / hexane / 760 Torr 6: tetra-n-butylammonium fluoride / tetrahydrofuran / 25 °C 7: 25 °C / saponification View Scheme

diisobutylaluminium hydride in dichloromethane T=0°C; 4 h;