Application
2-Hydroxy-4,5-dimethoxybenzoic acid phenyl ester is an important intermediate in the synthesis of 2-aminothiazole compounds. 2-Aminothiazole compounds are an important class of heterocyclic compounds in organic medicinal chemistry, possessing a wide range of biological activities. They can be used as local anesthetics and have anticonvulsant, antiviral, antibacterial, and insecticidal effects.
Synthesis
(1) Toluene (1.5 g), triphenyl phosphite (2.35 g), 2-hydroxy-4,5-dimethoxybenzoic acid (1.5 g) and concentrated sulfuric acid (40.3 μL) were mixed in a reaction flask under argon protection. The reaction mixture was refluxed under stirring conditions for 2.5 hours. After completion of the reaction, it was cooled to room temperature, methanol (5 g) was added and stirring was continued for 30 min. Subsequently, water (2.5 g) was added to the mixture and stirred for another 30 minutes. The precipitated crystals were filtered and dried under reduced pressure to afford phenyl 2-hydroxy-4,5-dimethoxybenzoate (2.0 g) in 96% yield.
References
[1] Patent: WO2006/22252, 2006, A1. Location in patent: Page/Page column 11
[2] Patent: US2013/253222, 2013, A1. Location in patent: Paragraph 0039
[3] Patent: CN105439977, 2016, A. Location in patent: Paragraph 0016
