Synthesis And Biological Activities Of Dicyclo And Dihydropyridine Containing Fluorine Neonicotinoids

Because of its unique mechanism of action, neonicotinoid insecticide, who has highinsecticidal activity, high specificity, low toxicity to mammals, no resistance to traditionalpesticides and other characteristics, is one important species of insecticide. But with thelong-term use of neonicotinoid insecticides, part of pests worldwide have a certain degreeof resistance, and the number of bees has significant reduction. Besides, neonicotinoidsinsecticide in the current market has a very similar molecular structure that heterocyclicand pharmacodynamic group are located trans position of double bond, the same mode ofaction (agonist of nAChRs), cross-resistance of each other. Therefore, the development ofnew neonicotinoid insecticide is very urgen.6-Cl-PMNI has high insecticidal activity, but its instability and weak hydrophobicitylimit effectiveness of crop protection. It is the lead compound in this article, and hetero-cyclic and pharmacodynamic group are located cis position of double bond by theformation of the inner light, which improve instability of6-Cl-PMNI. The formation ofether structure improve its weak hydrophobicity. I designed and synthesized38unreportedneonicotinoid insecticides, and all of compunds were detected by infrared spectroscopy (IR)and nuclear magnetic resonance spectroscopy (1H NMR), part of compunds were detectedby mass spectrometry (MS) and single crystal X-ray diffraction.A series of neonicotinoid with bicyclic structure(i): With AlCl3as catalyst,6-Cl-PMNI,containing α, β-unsaturated ketone and the corresponding alcohol reacted and constructedbicyclic structure in order to cis structure. Besides, dehydration reaction constructed etherstructure, so I synthesise16target compounds. Alcohol was both solvent and reactant. Andthis reaction has many advantages, such as mild reaction conditions, high yield withavoiding multi-step reaction. I selected AlCl3as catalysts due to fast response, lessby-products and easy separation.B series of neonicotinoid with dihydropyridine and fluorine(ii):6-Cl-PMNI, ethylorthoformate and ethyl trifluoroacetoacetate participated solvent-free and reflux reaction.The formation of a new six-membered ring was formed to build cis structure and ether structure was builded by dehydration, so22target compounds were synthesized. Thisreaction is fast response, simple operation, high yield, good stability of the product.In this paper, Aphis craccivora Koch, which is an important pest of legume crops, isthe test object of insecticidal activity. The result of biological activity test was showed asfollows:(1) When the concentration is500mg/L, the target compounds had a certain level ofbiological activity.(2) A series of compounds had high activity, and concentration of two compoundsmaking half of the of alfalfa aphid dead were1.615mg/L and1.980mg/L, higher thaninsecticidal activity of imidacloprid (LC50=2.744mg/L), as well as insecticidal activity ofone insecticide listed in2012. Preliminary electrophysiological of CSXA01and CSXA02showed resistant to nAChRs, which was different to most listed neonicotinoid. It may be anew configuration, the new features of the product in the future. According to the results, Isimply analyzed factors of biological activity, such as size of the inner ring, type ofheterocyclic and sterical resistance of substituents and electron-donating ability.(3) B series of compounds had certain degree high activity. When the concentration is500mg/L, corrected mortality of four compounds were more than80%. And Whenconcentration of CSXB22was100mg/L, corrected mortality was more than75%.