Hydrochloric Acid → 3-{4-[5-Methyl-2-(4-trifluoromethyl-phenyl)-oxazol-4-ylmethoxy]-phenyl}-hex-4-ynoic acid ethyl ester

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Reaction Steps

Cesium carbonate (0.51 g, 1.57 mmol) was added to a solution of 18.2 (216 mg, 0.79 mmol) and phenol 16 (220 mg, 0.79 mmol) in DMF (8 mL). The reaction was stirred at room temperature overnight and then taken up in water (500 mL). The solution was adjusted to pH=4.0 with 1N HCl(aq) and extracted with ethyl acetate (2×25 mL). The combined organics were washed with water, followed by brine. The solvent was removed under reduced pressure and the resulting residue was purified via radial chromatography (20% diethyl ether in hexanes) to yield 304 mg (82%) of 3-{4-[5-Methyl-2-(4-trifluoromethyl-phenyl)-oxazol-4-ylmethoxy]-phenyl}-hex-4-ynoic acid ethyl ester. LC/MSD m/e: 472.0 (M+H); 1H NMR (400 MHz) (CDCl3) δ 8.16 (2H, d, J=8.0 Hz), 7.73 (2H, d, J=8.0 Hz), 7.33 (2H, m), 6.99 (2H, m), 5.01 (2H, s), 4.14 (3H, m), 2.72 (2H, m), 2.48 (3H, s), 1.85 (3H, s), 1.26 (3H, t, J=8.0 Hz).

Provenance & Evidence