Study On The Synthetic Process Of Metalaxyl-M

The expansion of agricultural production is inseparable from the development of pesticides.Amide fungicides have also become widely concerned about a class of fungicides.Amide fungicides have a variety of chemical structure,distinctive mechanism of action,as well as efficient,wide range of effects,small toxicity,and environmentally friendly advantages,so that in the fungicide market a firm foothold.Metalaxyl is used for the treatment of a variety of plant downy mildew,phytophthora and other inhalation of fungicides,Metalaxyl-M is its R-single configuration of the body,the bactericidal effect is better.With the continuous advancement of science and technology,the product will have a greater market value.On the basis of reading a large number of domestic and foreign literatures,this paper introduces the synthetic methods of Metalaxyl-M spirit,analyzes the advantages and disadvantages of the existing methods in the literature,selects the best route for synthesizing the target products,and optimizes the synthetic process The And finally determined the route of S-lactic acid as the starting material,after esterification,sulfonylation,alkylation,chlorination and acylation reaction.The main side reactions in each reaction were discussed in detail by analyzing the reactions of each step.Under optimized conditions,reduce the amount of impurities,while avoiding product racemization.The total yield was 55.06%(in terms of S-lactic acid).Wherein the methoxyacetyl chloride used is prepared from methoxyacetic acid and thionyl chloride.The reaction conditions of the synthesis process are easy to realize,the operation is simple,the product yield is high,the chemical purity is high,the optical purity is high,and it is suitable for large-scale production.Finally,the analytical methods of optical purity were determined by means of nuclear magnetic identification structure,high performance liquid chromatography(HPLC),and the intermediates were characterized by gelatin and its intermediates.