(2-Nitro-phenyl)-acetic acid (2.0 g, 11.04 mmol), 4-amino-1-benzylpiperidine (2.25 mL, 10.03 mmol), 1-hydroxybenzotriazole (1.49 g, 11.04 mmol) and 1-(3-dimethylaminopropyl)-3-ethyl carbodiimide (2.3 g, 12.03 mmol) were combined in ethyl acetate (25 mL). To this solution was added triethylamine (4.2 mL. 30.1 mmol) and the reaction mixture stirred at 40° C. for 2 h. After cooling to room temperature, the mixture was diluted with ethyl acetate and washed with water (2×), 5% sodium bicarbonate, brine (2×), dried over sodium sulfate, and concentrated to afford 3.5 g (98%) of the desired product. LC/MS: tR=1.24 min, 354.30 (MH)+.
