1.1: 81 percent / TBAF / tetrahydrofuran / 0.08 h / 0 °C 2.1: MsCl; Et3N / CH2Cl2 / 1 h / -40 °C 2.2: 71 percent / LiCl / tetrahydrofuran; CH2Cl2 / 3 h / 20 °C 3.1: 70 percent / DIBAL-H / CH2Cl2; hexane / 3 h / -78 °C 4.1: NaH / tetrahydrofuran / 1 h / 20 °C 4.2: 53 percent / tetrahydrofuran / 12 h / 70 °C 5.1: (-)-sparteine; nBuLi / toluene; hexane / 1.5 h / -78 °C 6.1: TMEDA; tBuLi / tetrahydrofuran; pentane / 1 h / -78 °C 6.2: tetrahydrofuran; pentane / -78 °C 7.1: 93 mg / 1,2-dichloro-ethane / 3 h / Heating 8.1: 55 percent / MeSO3H; H2O / 16 h / Heating 9.1: Jones reagent / acetone / 0.08 h / 0 °C 10.1: 8.0 mg / aq. NaOH / methanol / 18 h / Heating View Scheme