Sulfuric Acid → 6-Bromo-4-(chloromethyl)-7-hydroxy-2H-1-benzopyran-2-one

Participants

Reaction Steps

A solution of 936.1 mg (4.953 mmol) 4-bromoresorcinol, concentrated sulfuric acid (5 mL) and ethyl 4-chloroacetoacetate (1 mL, 7.4 mmol) was stirred for 6 days at room temperature. The reaction mixture was poured into ice-water and stirred for 2 hours to give a fine precipitate. The precipitate was collected by filtration, washed with cold water and dried under vacuum over P2O5 to yield 847.6 mg (2.928 mmol, 59.1% yield) of compound 11 as a solid. 1H NMR (CD3OD) δ 7.96 (1H, s), 6.86 (1H, s), 6.43 (1H, s), 4.83 (2H, s).

Provenance & Evidence