1: 1,2-dichloro-ethane / 52 °C / also other temperatures (40.0 and 64.4 deg C); activation energy 2: 58 percent / potassium tert-butoxide / dimethylsulfoxide / 0.5 h 3: KOH / ethanol; H2O / 0.5 h / Heating 4: conc. aq. HCl / 5.5 h / Heating View Scheme