Trifluoroacetic acid → 4-Allyl-2-(4-methoxy-phenyl)-5-methyl-oxazole

Participants

Reaction Steps

The above prepared N-(1-acetyl-but-3-enyl)-4-methoxy-benzamide (6.45 g, 26.1 mmol) was stirred in a mixture of 43.9 ml of trifluoro-acetic acid (22 eq.) and 21.75 ml of trifluoro-acetic anhydride (6 eq.) for 7 h at 40° and for 16 h at ambient temperature. Pouring onto crashed ice, twofold extraction with EtOEt, three times washing with Na2CO3-solution, drying over natrium sulfate and evaporation of the solvents, followed by flash chromatography (SiO2, hexane/AcOEt=9/1) produced finally 4.51 g of the title compound as colorless oil.

Provenance & Evidence