The Process Optimization Of 1,1-Dimethoxy-2-Nitroethene And Cycloxaprid

Neonicotinoids are potent broad-spectrum insecticides with unique mechanism of action,low toxicity and environmentally friendly features.Neonicotinoids have become an important part in global integrated pest management.As one of neonicotinoids,cycloxaprid is the first acetylcholine receptor(nAChR)antagonist.It is a broad-spectrum insecticide with reduced toxicity to bees.It will have broad applications against rice planthopper,rice leafroller and imidacloprid resistant pests.Sodium methylate was used to replace 10%sodium hydroxide solution in tandem-synthesis of 1,1-dimethoxy-2-nitroethene.Not only the separation of 1,1-dichloro-2-nitro-ethylene was avoided,but also the waste water was decreased(11.3 tons waste water was decreased for the production of 1.0 ton 1,1-dimethoxy-2-nitroethene).By means of single factor experiment and orthogonal experiment,the yield of 1,1-dimethoxy-2-nitroethene was stable at 63.0%.Through the screening of solvents an bases,the purity of cycloxaprid was not less than 97.0%and two week degradation rate of hot storage stability test was not more than 5%.On the baseis of optimum conditions,4.7 tons waste water could be reduced for the production of 1.0 ton cycloxaprid.According to the new process,yield,purity and thermal storage stability of product was improved.And the reducing of waste water make the production process accord with the concept of EHS.