10.326 kg (166.3 mol) of ethylene glycol and 3.66 kg (83.185 mol) of freshly distilled acetaldehyde were added to the reaction vessel with slow stirring at room temperature for 30 minutes. Slowly 14.622 kg (91.504 mol) of bromine was added dropwise, with the rate of dropwise acceleration being controlled to maintain the reaction temperature at 0-3 °C. After the dropwise addition was completed, the reaction was continued at 0-3 °C for 3.5 hours. Upon completion of the reaction, decompression distillation was carried out to collect the fraction at 80-82 °C/3.6 kPa to give 11.002 kg (65.883 mol) of 2-bromomethyl-1,3-dioxolane in 79.2% yield, which was analyzed to be greater than 95%.
