To a solution of 2-(4-bromo-phenyl)-3-(3-diethylamino-pyrrolidin-1-yl)-propionic acid (590 mg, 1.6 mmol), DIPEA (1.03 g, 8 mmol), and Pybrop (1.12 g, 2.4 mmol) in CH2Cl2 (10 mL) was added 4-chloro-phenylamine (306 mg, 2.4 mmol). This mixture was stirred overnight at room temperature and then evaporated. The mixture redissolved in EtOAc (20 mL) and washed with water, brine, dried with Na2SO4, concentrated in vacuo. The residue was purified by flash column chromatography to give a white solid. MS: calc'd 478 (MH+), exp 478 (MH+).
