- Method for continuously synthesizing buprofezin
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The invention discloses a method for continuously synthesizing buprofezin, and belongs to the technical field of chemical synthesis. The method for continuously synthesizing buprofezin comprises the following steps: S1, continuously acylating N-methylaniline and phosgene in a solvent, and continuously deacidifying to obtain an acyl chloride solution; S2, carrying out continuous chlorination and continuous deacidification on the acyl chloride solution and chlorine under the action of an initiator to obtain a chloride solution; S3, adding buprothiourea, a catalyst and an acid-binding agent intothe chloride solution, carrying out continuous mixing reaction, crystallizing and drying a reaction product to obtain buprofezin of which the content is greater than or equal to 99.0% and the total yield is greater than or equal to 88% based on N-methylaniline. The method for continuously synthesizing buprofezin solves the defects caused by batch production in China, has the advantages of continuous reaction, high automation degree, small equipment size, high operation safety, few side reaction products, high conversion rate and good product quality, can effectively improve the production efficiency and reduce the production cost, and has very good popularization and application values.
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- Synthesis method of buprofezin
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The invention provides a synthesis method of buprofezin. The synthesis method comprises the following step: carrying out a cyclization reaction on raw materials including N-chloromethyl-N-phenylaminoformyl chloride and N-tert-butyl-N'-isopropylthiourea, wherein an acid binding agent takes acetate as a main component. According to the synthesis method provided by the invention, sodium acetate is adopted to replace ammonium bicarbonate and is used as alkali needed for synthesizing the buprofezin; the problem that solvent loss is caused by the release of carbon dioxide generated in a process of synthesizing a product through the ammonium bicarbonate is solved, and a byproduct, namely sodium chloride, can be directly filtered and removed and can be recycled to obtain certain economic benefit;meanwhile, energy consumption generated by wastewater treatment is reduced and zero emission of wastewater is realized; the average yield of the buprofezin prepared by adopting the synthesis method provided by the invention reaches 86 percent or more, and the content of the finished-product buprofezin reaches 97.0 percent or more.
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Paragraph 0045; 0054-0081
(2019/08/03)
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- Preparation method of buprofezin
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The invention provides a preparation method of buprofezin, comprising the steps of 1), adding sodium thiocyanate and water into an esterification kettle until dissolution; adding tertiary butanol andhydrochloric acid to obtain a mixed ester; allowing transposition and catalytic reaction to obtain t-butyl isothiocyanate; 2), adding the t-butyl isothiocyanate into chlorobenzene, stirring, dropwiseadding isopropyl amine to obtain 1-isopropyl-3-tert-butylthiourea solution; 3), adding N-methylaniline into chlorobenzene; introducing carbonyl chloride and chlorine gas in sequence to obtain N-chloromethyl-N-benzenecarbamoylchloride solution; 4), adding sodium bicarbonate into water, and adding the resultant into chlorobenzene; adding the 1-isopropyl-3-tert-butylthiourea solution; dropwise addingthe N-chloromethyl-N-benzenecarbamoylchloride solution, filtering, allowing layering, performing high-vacuum steaming to remove the chlorobenzene, crystallizing, centrifuging, and drying to obtain buprofezin. The substitutive average yield of the preparation process of buprofezin reaches 90% and above; the content of finished buprofezin reaches 98.0% and above; the preparation process is free ofammonia nitrogen wastewater.
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- Buprofenzin process for the preparation of
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The invention relates to a preparation method of buprofezin, which comprises the following steps of actinism, chlorination, synthesis and distillation crystallization. The actinism step employs dioxane or chloroform, the chlorination step employs dioxane or N-chloromethyl-N-phenyl carbamyl chloride as a solvent; and the synthesis step employs organic amine to participate in condensation. According to the invention, dioxane, chloroform or N-chloromethyl-N-phenyl carbamyl chloride are employed as the solvents, so that good dissolving performance is provided to the raw material, and the dioxane, chloroform or N-chloromethyl-N-phenyl carbamyl chloride has little solubility to HCL and is in favor of reaction, the production yield can reach as high as more than 82%; organic amine is employed for replacing ammonium bicarbonate as alkali for synthesis reaction, and can be recovered so that the discharge of ammonia nitrogen in waste water is reduced.
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