Synthesis
In a single-necked round-bottomed flask (2L), diethyl 2-(2-nitrobenzyl)malonate (8.7 g, 0.029 mol), 6N hydrochloric acid (131 mL) and acetic acid (131 mL) were added. The reaction mixture was heated and refluxed for 48 h, during which the reaction progress was monitored by thin layer chromatography (TLC). Upon completion of the reaction, the reaction mixture was alkalized with 6 M sodium hydroxide solution (500 mL) and subsequently extracted with ethyl acetate (3 x 250 mL). The organic phases were combined, dried with anhydrous magnesium sulfate and concentrated under reduced pressure to remove the solvent. The crude product was purified by column chromatography (silica gel: 100-200 mesh, eluent: 40% hexane solution of ethyl acetate) to give 3-(2-nitrophenyl)propionic acid (5.4 g, 94% yield).
References
[1] Patent: WO2010/127855, 2010, A1. Location in patent: Page/Page column 145; 146
[2] Chemische Berichte, 1923, vol. 56, p. 2450
[3] Patent: WO2005/40119, 2005, A1. Location in patent: Page/Page column 48-49
[4] Patent: WO2005/40100, 2005, A1. Location in patent: Page/Page column 75-77
