Synthesis Of The Pyriftalid And Research On Its Formulation Of Water Dispersible Granule

Pyriftalid belongs to pyrimidinylthiobenzoate compounds,it is produced by Syngenta,it is efficient、low toxicity and low residual and environmental protection pesticide,and it can be well applicated for future.At present,the main formulation of the Pyriftalid is 25%SC.This article mainly focuses on the synthetic route of the intermediate(3-methyl-7-nitrophthalide)of pyriftalid、the screening of the reaction conditions and the research about Pyriftalid water dispersible granule.Through a summary of existing paper,we fix a new synthetic route of the important intermediate(3-methyl-7-nitrophthalide).Using 3-Nitrophthalic acid,acetic anhydride and diethyl malonate as raw materials,3-methyl-7-nitrophthalide was successful synthesized through five-step reactions,such as dehydration-condensation、knoevenagel、hydrolysis decarboxylation、synthesis of sodium borohydride reduction and Pd/C catalytic hydrogenation;we make the route successful,through investigating the factors of each step for the experimental effect on the yield,such as reaction solvent,reaction temperature,reaction time and molar ratio and other factors ect.Under the optimized conditions of reactions,the total yield of 3-methyl-7-nitrophthalide was 49.8%,the purity was 98.4%.The structures of the product and the intermediate were confirmed by IR and 1H NMR.In addition,tentatively studying on the 25%WDG of Pyriftalid,through researching the Fillers,wetting agents,dispersing agents,disintegrating agents,binders and other additives for single factor experiments and Filtering to optimize the formulation experiments,ultimately determining the best formulation of 25%WDG of Pyriftalid,the final formulation is:Pyriftalid 25%,wetting agent LH-YLLS 2.5%,dispersing agent LH-EQLL 3.0%,Disintegrants(sodium alginate)2.5%,Binder(LH-120)2.0%,LH-120 2.5%,Emulsifier(LH-11)3.0%,Filler(bentonite)supplement 100%.