1: 88 percent / aq. N-methylmorpholine N-oxide; OsO4 / acetone / 2.5 h / 20 °C 2: 84 percent / p-TsOH / acetone / 20 °C 3: 92 percent / MeNH2 / ethanol / 2 h / Heating View Scheme

Multi-step reaction with 4 steps 1.1: sodium tetrahydroborate; cerium(III) chloride heptahydrate / methanol / 2 h / -70 - -60 °C2.1: 4-(N,N-dimethlyamino)pyridine; triethylamine / N,N-dimethyl-formamide / 16 h / 10 - 30 °C / Inert atmosphere3.1: disodium hydrogenphosphate / water / 14 h / 25 - 30 °C / pH 7 / Enzymatic reaction4.1: sodium hydride / tetrahydrofuran; mineral oil / 2 h / 25 - 45 °C / Inert atmosphere4.2: 22 h / 25 - 30 °C / Inert atmosphere