Technology for synthesizing pyraclostrobin by six-step method

Abstract

The invention provides a technology for synthesizing pyraclostrobin by a six-step method. The synthesis technology comprises the following steps: 1) performing a reduction reaction of ortho-nitrotoluene; 2) performing an acylation reaction of hydroxylamine; 3) performing a methylation reaction; 4) obtaining N-methoxyl-N-2-bromomethyl phenyl methyl carbamate through a bromination reaction; and 5) performing synthesis of 1-(4-chlorophenyl)pyrazolidine-3-ketone; and 6) performing synthesis of pyraclostrobin. Compared with the prior art, the preparation method has the advantages of simple process, easily available raw materials with low cost, and mild reaction condition, and the purity and yield of the target products are high.

Description

technical field [0001] The invention relates to the synthesis of pyraclostrobin, in particular to a six-step synthesis process for preparing pyraclostrobin. Background technique [0002] Azoxystrobin is a methyl methoxyacrylate broad-spectrum fungicide with a pyrazole structure discovered by BASF in 1993. It can prevent and control plant diseases caused by almost all types of fungal pathogens such as Ascomycetes, Basidiomycetes, Deuteromycetes and Oomycetes. At the same time, it is a hormone-type fungicide, which can make crops absorb more nitrogen , to promote the growth of crops. This variety is not only low in toxicity, safe for non-target organisms, but also safe and friendly to users and the environment. Pyraclostrobin can be processed into liquid, aqueous suspension, wettable powder, powder, ointment and other dosage forms. It can also be compounded and mixed with a variety of fungicides to increase the efficiency and expand the effect of fungicides. Since it was p...

AI Technical Summary

Problems solved by technology

[0006] The advantage of the first route is that the purification method is simple, which is conducive to the promotion of the purity of the final product, but the disadvantage is that the bromination of o-nitrotoluene is a low yield; the advantage of the second route is the disappearance of the strong electron-withdrawing group nitro, The yield of bromination is high, but due to the low yield of o-nitrotoluene reduction to hydroxylamine, the condensation yield of the last step is low and the purification of the final product is difficult