Study On The Synthesis Technology Improvement Of Pymetrozine & The Synthesis And Bioactivities Of Pymetrozine-Metal Complexes

The broad spectrum insecticide, pymetrozine, is a new heterocycle pesticide controlling aphids and white fillies, which has many characteristics such as high performance、low toxicity、high selectivity and environmentally friendly behavior. In recent years, pymetrozine has been concerned with its profound research value as a novel insecticide.A new synthetic route for industrial manufacture of pymetrozine was developed with the purpose of improvement on the disadvantages. In this article, we studied each reaction in the process of synthesis pymetrozine detailly and optimized some synthetic procedures. In this process, the original material ethyl acetate reacted with hydrazine hydrate by the condensation (yield 97.4%); In addition, by the cyclisation reacted with triphosgene (yield 90.3%); in the third step, reacted with chloroacetone by the alkylation (yield 84%); in the fourth step, reacted with hydrazine hydrate (80%) by the condensation (yield 93.7%), finally pymetrozine was formed by the hydrolysis under acidic condition and reacted with 3-pyridinecarboxaldehyde by the condensation (yield 92.1%).In addition,10 novel metal complexes were synthesized by reacting the ligands pymetrozine with metal salts of Zn (Ⅱ)、Cu (Ⅱ)、Mn (Ⅱ)、Ni (Ⅱ)、Ag (Ⅰ), these synthesized complexes were identified by atomic absorption spectrometry, elemental analysis and IR spectrum. We studied the Controlled Release Properties and found that the complexes of pymetrozine were evaluated for properties of the controlled release. For examples, the releasing ratios of Zn-complexes has exceeded 50% after 3h, the longer, the higher ratios, after 96h, the ratios of them has exceeded 80%.Finally, the bioactivities of pymetrozine and Zn (Ⅱ)、 Cu(Ⅱ)、Mn(Ⅱ)、Ni (Ⅱ)、Ag(Ⅰ) complexes with pymetrozine were determined by the white-backed planthoppers in laboratory. The test results showed Zinc acetate and Copper sulfate complexes had the higher bioactivities than pymetrozine at the same concentration. In the test, Zinc acetate complex has the same bioactivity at two different concentrations on account of its good controlled release property.