The invention provides a synthesis method of 3-chloro-5, 5-dimethyl-4, 5-dihydroisoxazole, which comprises the following steps: mixing isovaleric acid with a catalyst, pumping the mixture and
liquid chlorine into a mixer, uniformly mixing, and slowly introducing the mixture into a microchannel for reaction to obtain 2-chloroisovaleric acid; s2, uniformly mixing 2-chloroisovaleric acid in S1 with an
acylation reagent, and slowly introducing the mixture into the microchannel for reaction to obtain 3, 3-dimethyl crotonyl
chloride; adding
hydroxylamine hydrochloride or
hydroxylamine sulfate and a
solvent into the 3, 3-dimethyl crotonyl
chloride in the step S2 in a reaction kettle for dissolving, controlling the temperature of the
system to be 0-30 DEG C while stirring, adding alkali in batches, and stirring for reaction to obtain 5, 5-dimethyl-3-isoxazolidinone; and S3, diluting the 5, 5-dimethyl-3-isoxazolidinone obtained in the step S3 and a chlorination
reagent with a
solvent respectively, and then pumping the diluted 5, 5-dimethyl-3-isoxazolidinone and the chlorination
reagent into the microchannel reactor respectively for reaction to obtain the 3-chloro-5, 5-dimethyl-4, 5-dihydroisoxazole. In the production process,
tail gas is single in component and convenient to treat, and
environmental protection pressure is small; meanwhile, the used main raw materials are bulk and cheap chemicals, so that the production cost is lower.