Uses
Methyl 3-methyl-2-nitrobenzoate is used as a raw material for the synthesis of pesticide intermediate 2-amino-5-chloro-N,3-dimethylbenzamide, and is hydrogenated to produce 2-amino-3-methylbenzoic acid methyl ester.
Synthesis
Acetyl chloride (20 mL) was slowly added dropwise to a suspension of commercially available 3-methyl-2-nitrobenzoic acid (13.45 g, 74.25 mmol) in methanol (200 mL) at 0 °C. The reaction mixture was then heated to reflux temperature with continuous stirring for 20 hours. Upon completion of the reaction, the solvent was removed by distillation under reduced pressure. The residue was dissolved in ethyl acetate (800 mL) and washed sequentially with saturated aqueous NaHCO3 (200 mL) and brine (150 mL). The organic phase was dried over anhydrous Na2SO4 and concentrated under reduced pressure to afford methyl 3-methyl-2-nitrobenzoate as a white solid (12.35 g, 85% yield). The product was characterized by 1H NMR (CDCl3): δ 2.36 (s, 3H), 3.89 (s, 3H), 7.40-7.51 (m, 2H), 7.84 (m, 1H).
References
[1] Tetrahedron, 2013, vol. 69, # 32, p. 6679 - 6686
[2] Tetrahedron, 2004, vol. 60, # 10, p. 2235 - 2246
[3] Patent: WO2005/66136, 2005, A1. Location in patent: Page/Page column 87-88
[4] Patent: CN106467513, 2017, A. Location in patent: Paragraph 0009; 0036; 0037; 0038; 0039
[5] Chemische Berichte, 1907, vol. 40, p. 4413