The invention provides a synthesis method of
fluxapyroxad, which belongs to the technical field of
chemical synthesis and comprises the following steps: mixing
nickel chloride hexahydrate, tetraethoxysilane and
potassium hydrogen oxalate in water, performing high-
temperature treatment, cooling, separating and
drying to obtain a
nickel-based
silicate carrier; loading aluminum
chloride and
ferric citrate on a
nickel-based
silicate carrier to obtain a composite catalyst; the preparation method comprises the following steps: mixing 3-(difluoromethyl)-1-methyl-1H-
pyrazole-4-
carboxylic acid,
thionyl chloride, N, N-
dimethylformamide and a composite catalyst, heating and stirring, cooling and separating, and carrying out reduced pressure
distillation to obtain a
mixed solution; mixing 3 ', 4', 5 '-trifluorobiphenyl-2-amine,
toluene, the composite catalyst and the
mixed solution, heating and stirring, cooling and separating, performing reduced pressure
distillation, stirring and pulping, centrifugally washing and
drying to obtain the
fluxapyroxad. The
fluxapyroxad prepared by the method is higher in purity and yield, an additional acid-binding agent does not need to be added in the preparation process, the influence caused by byproducts is reduced, and the fluxapyroxad has a good industrial application prospect.