Oxalyl chloride (0.765 mL, 8.73 mmol) was added to a suspension of 4-(phenylmethyl)-2-morpholinecarboxylic acid (1.288 g, 5.82 mmol) and DMF (0.090 mL, 1.165 mmol) in CH2Cl2 (80 mL) at 0° C. over 10 minutes. The reaction mixture was stirred at 25° C. for 2 h, and then concentrated. The residue was dissolved in CH2Cl2 (80 mL), then triethylamine (2.029 mL, 14.56 mmol) and 2-amino-1-(2-chlorophenyl)ethanone (1.2 g, 5.82 mmol) were added to the brown solution at 0° C. The mixture was stirred at 25° C. for 3 hours, and at this time, water (150 mL) was added. The mixture was extracted with EtOAc (3×100 mL), and the combined organics were dried with anhydrous Na2SO4, filtered, and concentrated. The resulting residue was purified by silica gel chromatography using 50% EtOAc in petroleum ether to afford the title compound (350 mg) as a pale yellow solid. LC-MS (ES) m/z=373 [M+H]+.
