This invention belongs to the field of
organic synthesis technology and relates to a method for synthesizing 3,4-difluoro-2-methoxyphenylacetic acid, comprising the following steps: S1 Using 3,4-difluoro-2-methoxyaniline and a diazotizing
reagent as raw materials, a diazotization reaction is carried out under the action of a
copper catalyst and an inorganic acid to obtain the 3,4-difluoro-2-methoxyaniline diazonium salt; subsequently, a
Sandmeyer reaction is performed with
bromine to obtain 6-bromo-2,3-difluoroanisole; S2 The 6-bromo-2,3-difluoroanisole obtained in step S1 is reacted with
diethyl malonate under the action of a
ferricyanide to obtain 2-(3,4-difluoro-2-methoxyphenyl)
malonic acid; S3 The 2-(3,4-difluoro-2-methoxyphenyl)
malonic acid obtained in step S2 is reacted with concentrated
sulfuric acid to obtain 3,4-difluoro-2-methoxyphenylacetic acid. This invention features mild
reaction conditions, high yield, and high purity, making it suitable for industrial production.