TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (claimed): The preparation of (I) comprises adding cyanuric chloride and solvent acetone in reaction container, dripping aminobenzotrifluoride-containing solvent acetone to reaction container while stirring, adding sodium carbonate solution to adjust pH to 5-7, separating solid, recrystallizing to obtain product 2,4-dichloro-6-(4-trifluoromethane aniline)-1,3,5-triazine, with mol ratio of aminobenzotrifluoride to cyanuric chloride at 1:1-1.2; taking 4-chloro-aniline to dissolve in acetone, dripping sodium bicarbonate solution while stirring, adding acetone solution of 2,4-dichloro-6-(4-trifluoromethane aniline)-1,3,5-triazine, desolventizing to obtain crude product, dissolving crude product in ethyl acetate, washing by water, drying ethyl acetate layer via anhydrous sodium sulfate, decompressing to remove solvent, and obtaining 2-chloro-4-(4-chlorobenzene amido)-6-(4-chlorobenzene amido)-1,3,5-triazine via column chromatography purification, with mol ratio of the 2,4-dichloro-6-(4-trifluoromethane aniline)-1,3,5-triazine to 4-cholrine-aniline and sodium bicarbonate at 1:1-1.2:1-1.2; and adding dimethylamine aqueous solution to solvent 1,4-dioxane, adding sodium bicarbonate aqueous solution to reaction system, adding 2-chloro-4-(4-chlorobenzene amido)-6-(4-chlorobenzene amido)-1,3,5-triazine while stirring, dissolving to obtain crude product, dissolving obtained crude product in acetate to remove salt, decompressing to remove solvent, and obtaining 2-dimethylamino-4-(4-chlorobenzene amido)-6-(4-trifluoromethane aniline)-1,3,5-triazine, with mol ratio of 2-dimethylamino-4-(4-chlorobenzeneamido)-6-(4-trifluoromethane aniline)-1,3,5-triazine to the dimethylamine to sodium bicarbonate at 1:1-1.2:1-1.2. Preferred Processes: The reaction is - 5 to 5 degrees C, and reaction time is 2-4 hours. The reaction temperature in preparing 2-chloro-4-(4-chlorobenzene amido)-6-(4-chlorobenzene amido)-1,3,5-triazine is 20-25 degrees C, and reaction time is 5-30 minutes. The reaction temperature in synthesis of 2-dimethylamino-4-(4-chlorobenzene amido)-6-(4-trifluoromethane aniline)-1,3,5-triazine is 70-100 degrees C, and the reaction time is 1-3 hours. ACTIVITY - Insecticide.