1: 49 percent / lead tetraacetate, CaCO3, I2 / benzene / 2.5 h / Heating 2: 81 percent / KOH / propan-2-ol; H2O / 18 h / Heating View Scheme

Multi-step reaction with 2 steps 1: 50 percent / aq. KOH / ethanol; H2O / 70 h / 25 °C2: 76 percent / platinum oxide, NaNO2, H2 / ethanol / 2.5 h / 2068.6 Torr  

Multi-step reaction with 2 steps 1: 81 percent / zinc, acetic acid / methanol / 17 h / 25 °C2: 76 percent / platinum oxide, NaNO2, H2 / ethanol / 2.5 h / 2068.6 Torr