Synthesis of the Intermediate of Nitenpyram
|School||Nanjing University of Technology|
|Keywords||insecticides nitenpyram intermediate product synthesis|
Nitenpyram is a new chloro-nicotine type insecticide. It possesses good properties of high efficiency, low poison, better environmental safety, quick in preliminary effect, long in effective persistency, high internal absorbability, and showing no mutual anti-effects. Synthesis methods of Nitenpyram from intermediate products are outlined. Meanwhile, the synthesis of intermediate products is introduced.The vinylidene chloride was produced by reacting 1,1,2- trichlorethane and sodium hydroxide. Effects of temperature, reaction time, molar ratio of 1,1,2- trichlorethane and sodium hydroxide on the yield of vinylidene chloride were discussed,The optimum operation conditions were as followed: reaction temperature of 65℃, reaction time for 1.5h, at the molar ratio of 1,1,2- trichlorethane and sodium hydroxide 1:1.15.The purity is 95%.The yield was 99%.The1,1-dichloro-2-nitro-ethylene was produced by reacting vinylidene chloride with nitric acid and hydrogen chloride. Effects of temperature, reaction time, molar ratio of vinylidene chloride and nitric acid and hydrogen chloride on the yield were discussed.The optimum operation conditions were as followed: reaction temperature of 20℃,reaction time for 3h,n(nitric acid):n(hydrogen chloride):n(vinylidene chloride)=1.3:1.3:1.The purity was 94%. The yield was 85%(vinylidene chloride). Structure of Cl2C=CH-NO2 was characterized by GC-MS. The N-(6-chloro-3-pyridyl) methyl-N-ethylamine was produced by reacting 2-chloro-5-chloro-methylpyridine and ethylamine. Effects of temperature, reaction time, molar ratio of 2-chloro-5-chloro-methylpyridine and ethylamine on the yield were discussed. The optimum operation conditions were as followed: at the roomtemperature for 1.5h, at the molar ratio of 2-chloro-5-chloro-methylpyridineand ethylamine 1:5. The purity was 92%.The yield was 97%.Structure of compound was characterized by GC-MS. ⅰ <WP=5>The1,1-bis(methylthio)-2-nitroethene was produced by reacting nitromethane and carbon bisulfide. Effects of temperature, reaction time, methylating agent, solvent,molar ratio of nitromethane and carbon bisulfide on yield of 1,1-bis(methylthio)-2-nitroethane were discussed. The optimum operation conditions were as followed: the reaction temperature of 35℃, reaction time for 3.0h. In the processof dimethyl sulfate methylation, the optimum operation condition was at the room temperature for 3.0h. The yield was 84%. Crude product was purified by recrystalliation. 1,1-Bis(methylthio)-2-nitroethene was characterized by IR and 1H-NMR.