57280-22-5

1003-83-4

57280-22-5

1) 1810 kg of 4,7-dihydro-2,2-dimethyl-1,3-dioxepin (Compound A-3), 1730 kg of acetonitrile, 1480 kg of methanol, and 1920 kg of water were added to the reaction vessel, followed by 15.1 kg of disodium hydrogen phosphate; the reaction solution was stirred and heated. 2) 1990 kg of 27% hydrogen peroxide and 1086 kg of aqueous 1 M sodium hydroxide were added to the reactor, and the reaction temperature was controlled at 60-80°C; the pH was maintained at 7-9.5 during the reaction. 3) After the reaction was completed, the reaction solution was stirred to room temperature for 8 to 9 hours. 4) 2880 kg of saturated brine and 6335 kg of dichloromethane were sequentially added to the reactor, and the organic phase was separated after stirring. 5) Add 4010 kg of sodium sulfite solution to the organic phase, stir and dry the organic phase. 6) After drying, the organic phase was filtered and the solvent was removed by distillation at 40°C to obtain a crude product of 4,4-dimethyl-3,5,8-trioxabicyclo[5.1.0]octane (Compound A). (7) The crude compound A was subjected to decompression distillation to obtain the pure compound A (1820 kg, total yield: 85.2%), which was tested to be ≥99.6% pure.