Cesium carbonate → HCID 23590013, compound

Participants

Reaction Steps

4-[2-(2-Phenyloxazol-4-yl)ethoxy]phenol (3.7 g, 13.0 mmol) and cesium carbonate (4.71 g, 14.5 mmol) were suspended in anhydrous DMF (100 mL) and treated with dropwise addition of ethyl 2-bromoisobutyrate (2.54 g, 13.0 mmol, 1.93 mL). The reaction mixture was stirred at ambient temperature for 24 h and then partitioned between ether (200 mL) and 1.0 N HCl (200 mL). The organic layer was washed with water (100 mL), dried over MgSO4 and concentrated to a brown oil, which was purified by gradient column chromatography (200 mL SiO2, 100% hexanes to 20% EtOAc/hexanes) to provide 2-methyl-2-{4-[2-(2-phenyloxazol-4-yl)ethoxy]phenoxy}propionic acid, ethyl ester (2.54 g, 50%) as a colorless, viscous oil: Rf=0.5 in 20% EtOAc/hexanes; 1H NMR (250 MHz, CDCl3) δ 7.96-8.02 (m, 2H), 7.37-7.46 (m, 3H), 6.81 (s, 4H), 4.32 (q, 2H), 4.20 (t, 2H), 3.03 (t, 2H), 1.52 (s, 6H), 1.27 (t, 3H).

Provenance & Evidence