Potassium Carbonate → Hexafluoroacetone monohydrate

In a 50-ml three-necked flask were placed 7.59 g (17.2 mmol) of the aqueous 56.8% potassium 3,3,3-trifluoro-2-trifluoromethyl-2-hydroxypropionate solution prepared in Reference Example 1 and 4.98 g (36 mmol) of potassium carbonate. 25 g of water was added to dissolve the mixture. The pH was 13. 5.75 g (36 mmol) of bromine was added dropwise over 60 minutes while stirring the mixture under heat at 40° C. in a water bath. After the completion of dropwise addition, the reaction was further performed at the same temperature for 3 hours, and the reaction was complete. The pH when the reaction was complete was 7 to 8. Hexafluoroacetone hydrate was obtained at a starting material conversion of 64% with a selectivity of 99% or higher.