Synthesis
General procedure for the synthesis of o-aminophenylacetonitrile from 2-nitrophenylacetonitrile: 2-nitrophenylacetonitrile (30 g, 185 mmol) and 10% palladium/carbon catalyst (2 g) were suspended in acetic acid (450 mL). The suspension was transferred to a Parr hydrogenation unit and the hydrogenation reaction was carried out at 30 psi hydrogen pressure and room temperature for 2 hours. Upon completion of the reaction, the reaction mixture was filtered through a Celite pad to remove the catalyst. The filtrate was concentrated to dryness under reduced pressure. The resulting residue was dissolved in ethyl acetate (250 mL) and washed sequentially with water (2 x 100 mL) and saturated sodium chloride solution (50 mL). The organic phase was dried over anhydrous sodium sulfate, filtered and concentrated. The crude product was purified by column chromatography (100-200 mesh silica gel) using petroleum ether solution of 8% ethyl acetate as eluent to give o-aminophenylacetonitrile (13.5 g, 55% yield) as a white solid.1H NMR (CDCl3) δ ppm: 7.3-7.1 (m, 2H), 6.9-6.7 (m, 2H), 3.7 (br, 2H), 3.5 (s, 2H).
References
[1] Chemical and Pharmaceutical Bulletin, 1983, vol. 31, # 10, p. 3424 - 3445
[2] Patent: US2011/111046, 2011, A1. Location in patent: Page/Page column 17
[3] Patent: WO2011/58473, 2011, A1. Location in patent: Page/Page column 34; 35
[4] Tetrahedron Letters, 2006, vol. 47, # 2, p. 159 - 162
[5] Journal of the American Chemical Society, 1950, vol. 72, p. 3047,3049
