1: 96 percent / NaN3; NH4Cl / H2O; acetone / 23 h / Heating 2: DMAP / CH2Cl2 / 4 h / 20 °C 3: H2 / 10 percent Pd/C / methanol / 48 h / 20 °C / 760 Torr 4: 90 percent / DEAD; PPh3 / benzene / 20 h / 20 °C 5: 90 percent / 1N aq. HCl / methanol / 2 h / Heating View Scheme

gold(III) chloride; silver hexafluoroantimonate in 1,4-dioxane T=20°C; 0.166667 h; regioselective reaction;

With  oxygen; isobutyraldehyde; μ-dimethoxo diferric salen in  dichloromethane T=25°C; P=760 Torr; 21 h;