5-Fluororesorcinol → Umbelliferone

Beteiligte Stoffe

Reaktionsschritte

1-Fluoro-3,5-dihydroxybenzene (1.0 g, 7.8 mmol) and ethyl 2-benzyl acetoacetate (1.72 g, 7.8 mmol) are suspended in 20 mL of 70% sulfuric acid at room temperature. The reaction mixture is stirred for 24 hours and poured into ice water. The solid is filtered and washed with water. The yellowish crude product is re-crystallized from hot ethanol to afford the 7-hydroxy coumarin intermediate (929 mg, 42%).

Herkunft & Nachweise