Study On The Synthesis Of 3-Isochromanone

3-Isochromanone and its substituted derivatives are important intermediates in producing the pharmaceutical and agrochemical products, especially for the synthesis of Strobilurins fungicides. Its mechanism of action is inhibition of mitochondrial respiration, with high efficiency, spectral and environment-friendly features.In the first chapter, the development of strobilurin fungicides nowadays and several types of common fungicides are briefly introduced, methoxyimino acetate (one kind of active groups for Strobilurins fungicide)is chosen as an example to emphasize the importance of 3-isochromanone in synthesizing such an active group.In the second chapter, the synthetic methods of 3-isochromanone reported in the past literatures are firstly summarized, which provides an important basis for the title; then the process for synthesizing 3-isochromanone is discussed in detail, and finally comes an optimum synthetic route.O-methyl benzyl cyanide, instead of o-methyl benzyl chloride, is chosen as a raw material to avoid the use of highly toxic sodium cyanide, and o-methylphenylacetic acid is got through hydrolysis; After that, o-chloromethyl phenylacetate is synthesized by dropping sulfuryl chloride instead of ventilating chlorine, and the formation of polychlorinated products are reduced by controlling the reaction temperature and reaction time at the same time; Without the addition of catalyst, nucleophilic substitution reaction is directly carried out in the aqueous phase with basic conditions to get 3-isochromanone. The product is conformed by 1H NMR to be the target compounds, and the structure of by-product is also determined by 1H NMR and 13C NMR.The synthetic method and crafts improvement are deeply discussed in this article. The advantage of this crafts is that the reaction route is simple and the materials are cheap and readily available, we slao have a detailed analysis on the by-product, whichmay infact the yield and purity of final product, and at the same time, a treatment approach to exhaust gas produced in the chlorinated reaction is also informed. The reaction is designed to use low toxic reagents or no solvent, in this way, the pollution to the surrounding environment is reduced to some extent. In this article, you can also get a detailed introduction of 3-isochromanone in the synthesis of strobilurins fungicides. By optimizing the synthetic process, the yield and purity of final product are significantly improved, its less demanding for response equipment makes it more suitable for industrial production, and the recovery of the raw material and reagent reduce the production cost effectively.