Vinylene carbonate → 2-(4-Methylphenyl)-1,3-oxazole

Participants

Reaction Conditions

Reaction Steps

Polyphosphoric acid (20 g), vinylene carbonate (5.73 mL, 90.0 mmol) and p-toluamide (12.2 g, 90.0 mmol) were combined and heated at 170° C. for 2 h. The reaction mixture was allowed to cool to ˜80° C., water (˜100 mL) was carefully added, and stirred for ˜10 min. This mixture was extracted three times with ethyl acetate, combined organic extracts were dried with Na2SO4, and concentrated in vacuo. Purification by medium pressure liquid chromatography (SiO2, 97:3 hexanes/acetone) gave 6.41 g (45%) of the title compound. MS 160 (M+H)+.

Provenance & Evidence