1.1: dioxane / 16 h / Heating 1.2: water / dioxane / 1 h / Heating 2.1: KOH / methanol / 2 h / 20 °C 3.1: 2.86 g / sodium acetate; acetic anhydride / 3 h / Heating 4.1: DIBAL-H / tetrahydrofuran / -25 - 0 °C 5.1: tBuLi / tetrahydrofuran; pentane / -50 - 0 °C 5.2: 25 percent / tetrahydrofuran; pentane / 3 h / 20 °C 6.1: 99 percent / oxygen / Rose Bengal / methanol / 3 h / -78 °C / Irradiation 7.1: 52 percent / thionyl chloride / CH2Cl2 / 18 h / 20 °C View Scheme