The invention discloses a preparation method of trifluoropropionate, which comprises the following steps: 1, dissolving
alkyl acetate in
tetrahydrofuran, dropwise adding a
lithium diisopropylamide-
tetrahydrofuran solution under the conditions of
nitrogen protection and temperature not higher than-60 DEG C, and stirring for reaction after dropwise adding; 2, dropwise adding trimethylchlorosilane, and stirring for reaction; 3,
quenching with
ice water, extracting with a first
organic solvent, washing with a saturated
saline solution,
drying, filtering and spin-
drying to obtain a trimethyl [[1-(alkoxy) vinyl] oxy]-
silane crude product; 4, dissolving the trimethyl [[1-(alkoxy) vinyl] oxy]-
silane crude product in a second
organic solvent, adding a catalyst and a
trifluoromethylation reagent at the temperature of-10 DEG C to 0 DEG C under the protection of
nitrogen, and after addition, recovering to
room temperature for stirring reaction; the trifluoro
methylation reagent is a Togni
reagent I or a Togni reagent II, and the trifluoro
methylation reagent is a trifluoro
methylation reagent or a trifluoro methylation reagent or a trifluoro methylation reagent or a trifluoro methylation reagent. 5, adding water for
quenching, extracting,
drying and performing rotary
evaporation to obtain a crude product, and passing through a column to obtain a product; the method has the advantages that the yield is high, the affinity to the environment is good, and the raw materials are easy to obtain.