A mixture of ethyl 3-bromo-4-cyanobenzoate (500 mg, 1.97 mmol), XANTPHOS (228 mg, 0.39 mmol), cesium carbonate (1.282 g, 3.94 mmol), cyclopentylamine (233 mg, 2.75 mmol), and tris(dibenzylideneacetone)dipalladium (180 mg, 0.20 mmol) in dioxane (5 mL) was stirred at 100° C. for 17 h. The reaction mixture was partitioned between ethyl acetate (100 mL) and water (50 mL), the organic layer washed with brine (50 mL), dried over sodium sulfate, filtered and concentrated. Column chromatography on silica (hexanes:ethyl acetate 9:1) afforded ethyl 4-cyano-3-(cyclopentylamino)benzoate (366 mg, 72% yield) as a brown oil. 1H NMR (400 MHz, CDCl3): 7.43 (m, 2H), 7.35 (m, 1H), 7.27 (m, 1H), 4.62 (d, 1H), 4.38 (q, 2H), 3.93 (m, 1H), 2.10 (m, 2H), 1.78 (m, 2H), 1.67 (m, 2H), 1.53 (m, 2H), 1.39 (t, 3H). MS (EI) for C15H18N2O2: 259 (MH+).
