Potassium Carbonate → (E)-3-(benzooxazol-4-yloxy)-but-2-enoic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

A stirred mixture of benzooxazol-4-ol (0.388 g, 2.87 mmol), ethyl-2-butynoate (1.93 g, 17.2 mmol) a catalytic amount of 4-dimethylaminopyridine and potassium carbonate (0.595 g, 4.30 mmol) in tetrahydrofuran (20 mL) was placed in a sealed tube and heated at 80° C. for 2 h. The reaction mixture was filtered and the filtrate was collected and concentrated in vacuo. The resulting residue was purified by ISCO column chromatography (Silicycle 40 g, 2% to 15% ethyl acetate/hexanes) which afforded (E)-3-(benzooxazol-4-yloxy)-but-2-enoic acid ethyl ester (710 mg, 100%) as a light yellow solid.

Provenance & Evidence