1.1: Mn; 2,5,6-collidine; Me3SiCl / Cp2TiCl2 / tetrahydrofuran / 2 h / 20 °C 1.2: 47 percent / Bu4NF / tetrahydrofuran / 3 h 2.1: 95 percent / imidazole / dimethylformamide / 3 h / 20 °C 3.1: 98 percent / K2CO3 / methanol / 2 h 4.1: PCC / CH2Cl2 / 1 h / 20 °C 5.1: K2CO3 / methanol / 1.5 h / 20 °C 6.1: 550 mg / LiAlH4 / diethyl ether / 3 h / 0 °C 7.1: CBr4; PPh3 / benzene / 2 h / 0 °C 8.1: 75 percent / Mn / Cp2TiCl2 / tetrahydrofuran / 20 °C 9.1: 90 percent / TBAF / tetrahydrofuran / 11 h / 60 °C View Scheme

<b>Multi-step reaction with 4 steps<br /> </b>1: 99.5 percent / pyridine / 1 h / Ambient temperature<br />2: 26.1 percent / SeO₂, t-BuOOH / CH₂Cl₂ / 3.5 h / 10 &deg;C<br />3: 80.6 percent / Ti(i-PrO)4, L-(+)-weinsaeure-diaethylester, t-BuOOH / CH₂Cl₂ / 14 h / -20 &deg;C<br />4: 1.) TsCl; 2.) NaI; 3.) NaBH₃CN / 1.) pyridin, 4 degC, 14 h; 2.) aceton, reflux, 2.5 h; 3.) THF-HMPA, 60 degC, 4.5 h<br /> <br /> &nbsp;