1.1: 82 percent / NMO; aq. OsO4 / tetrahydrofuran / 5 h / 20 °C 2.1: 92 percent / aq. NaIO4 / tetrahydrofuran / 1 h / 20 °C 3.1: MgSO4 / tetrahydrofuran; methanol / 20 °C 3.2: 85 percent / NaBH4 / tetrahydrofuran; methanol / 1 h 4.1: 100 percent / iPr2NH; tetramethylenediamine; n-BuLi / tetrahydrofuran; hexane / -78 - 20 °C 5.1: 94 percent / NaSEt / dimethylformamide / 5 h / 130 °C View Scheme