Cesium carbonate → 4-(2-Amino-thiazol-5-yloxy)-3-fluoro-benzoic acid ethyl ester

Beteiligte Stoffe

Reaktionsschritte

To a solution of 5-Bromothiazole-2-amine hydrobromide (1.55 g, 5.97 mmol) in acetone (100 mL) was added 3-fluoro-4-hydroxy benzoic acid ethyl ester (1.1 g, 5.97 mmol) and cesium carbonate (3.89 g, 11.94 mmol) under argon atmosphere and refluxed for 5 hrs. The reaction mixture was cooled to room temperature and filtered; the filtrate was concentrated under reduced pressure. The residue was partitioned in between ethyl acetate and water. The layers were separated, the organic layer was washed with cold 2 N NaOH (10 mL), brine and dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to provide 4-(2-amino-thiazol-5-yloxy)-3-fluoro-benzoic acid ethyl ester (0.68 gm).

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