4-Bromomethyl-3-ethyl-isoxazole-5-carboxylic acid ethyl ester (1.03 g, 3.93 mmol) was dissolved in 40 mL of acetonitrile. N-(2,4-dimethoxybenzyl)glycine ethyl ester (1.09 g, 4.32 mmol), potassium carbonate (1.63 g, 11.8 mmol) and potassium iodide (0.98 g, 5.90 mmol) were added, and the mixture was stirred at room temperature for 16 h. The solvent was removed in vacuo and the residue was partitioned between CH2Cl2 and water. The aqueous layer was extracted with additional CH2Cl2 and the combined organic layer was dried over MgSO4 and concentrated. The crude oil was purified by flash chromatography (0-30% EtOAc/hexanes) to give 0.88 g of the title compound. MS: (+) m/z 435.53 (M+1).
