After mixing 2243 g (20 mol) of 1,4-cyclohexanedione, 2607 g (42 mol) of ethylene glycol, the resin filtered, and 26 L of toluene, the temperature was raised slowly and refluxed for 11 hours to separate the water. The reaction temperature was lowered to 40° C., the resin was filtered, and the organic phase was concentrated until no liquid flowed. Then add 1257g (21mol) of methylboronic acid and 20L of n-heptane, raise the temperature to 80°C and react for 6 hours, then slowly cool down to 5-10°C in a gradient, filter, rinse the filter cake with n-heptane, and dry to obtain 1,4-Cyclohexanedione bis(ethylene ketal).
