1.1: diisopropylamine; n-BuLi / tetrahydrofuran; hexane / 4 h / -78 °C 1.2: 89 percent / tetrahydrofuran; hexane / 16 h / 23 °C 2.1: BH3*SMe2 / tetrahydrofuran / 72 h / 23 °C 2.2: 51 percent / NaOH; aq. H2O2 / tetrahydrofuran / 48 h / 23 °C 3.1: 81 percent / camphorsulfonic acid / benzene / 24 h / 80 °C 4.1: DIBAL-H / toluene; CH2Cl2 / 5 h / -78 °C 5.1: 0.341 g / pyridine; 4-dimethylaminopyridine / toluene; CH2Cl2 / 24.5 h / -78 - 23 °C View Scheme