A kind of production technology that uses solid superacid to synthesize tricyclazole

Abstract

The invention discloses a production process for synthesizing tricyclazole by using a solid super acid. The process takes an intermediate 4-methyl-2-hydrazinobenzothiazole as a raw material, formic acid as a ring-closing agent, chlorobenzene as a solvent, and the solid super acid as a catalyst for synthesizing the tricyclazole, wherein the solid super acid is perfluorosulfonic acid resin. The process comprises the following steps: mixing 4-methyl-2-hydrazinobenzothiazole with chlorobenzene, then adding formic acid, conducting heating for refluxing until the 4-methyl-2-hydrazinobenzothiazole iscompletely converted into an oximido intermediate; then adding the solid super acid, conducting refluxing for dehydrating, when the reaction reaches the end point, filtering out the solid super acidwhile the system is hot, then removing the solvent from the mother liquor, adding water for crystallization, conducting cooling, filtering, water washing and drying to obtain the tricyclazole. The production process disclosed by the invention creatively introduces the solid super acid as the catalyst, and uses a slight excess of formic acid to efficiently synthesize the tricyclazole, thereby increasing the utilization rate of formic acid from 10% to 70% or more, and greatly improving the utilization rate of formic acid.

Description

technical field

[0001] The invention relates to the technical field of pesticides, in particular to a production process for synthesizing tricyclazole with a solid superacid. Background technique

[0002] Tricyclazole is a special fungicide for the control of rice blast. It belongs to the thiazole tricyclazole. It has the characteristics of high efficiency, long-lasting effect and less frequency of use in the field control of rice blast. Its bactericidal mechanism is mainly to inhibit the formation of episporium melanin, thereby inhibiting spore germination and epispora formation, preventing the invasion of pathogens and reducing the production of spores of blast fungus.

[0003] There are many synthetic routes for the synthesis of tricyclazole. At present, the vast majority of production units use o-toluidine as the starting material to prepare through the synthetic route of condensation, cyclization, substitution, and secondary cyclization. In the last step In the reactio...

Images