Synthesis
Fuming nitric acid (20 mL) was slowly added dropwise to the homophthalic acid at 0°C. The reaction mixture was then stirred continuously for 5 hours at room temperature. Upon completion of the reaction, the mixture was carefully poured into ice water to quench the reaction. The precipitated solid product was collected by filtration and washed well with cold water. Finally, the product was dried in a desiccator to afford 2-(carboxymethyl)-5-nitrobenzoic acid (2.01 g, 32% yield). The product was analyzed by ESI/APCI(+) mass spectrometry, showing a molecular ion peak m/z of 207.8 ([M+H]+).
References
[1] Journal of Medicinal Chemistry, 2008, vol. 51, # 24, p. 7717 - 7730
[2] Patent: WO2012/85003, 2012, A1. Location in patent: Page/Page column 111-112
[3] Bioorganic and Medicinal Chemistry, 2003, vol. 11, # 14, p. 3141 - 3152
[4] Tetrahedron, 2017, vol. 73, # 7, p. 819 - 828
[5] Journal of Medicinal Chemistry, 2015, vol. 58, # 7, p. 3188 - 3208