反应详情

To the solution of 0.8 gram (3.0 mmoles) of 2-trimethylsilyl-naphtho[2,3-b]furan-4,9-dione in 20 mL of acetonitrile at room temperature, 0.53 grams (3.3 mmoles) of bromine in 20 mL of acetonitrile was added dropwise over 5 minutes. The mixture was further stirred for 30 minutes at room temperature, and then evaporated to dryness. The residue was crystallized in ethanol/water. Pure crystal product was filtered and dried under vacuum. 0.75 grams of product (yield 90%) was obtained and characterized by 1H NMR and mass spectrum. 1H NMR (in CDCl3) δ 6.96 (s, 1H), 7.76-7.82 (m, 2H), 8.18-8.25 (m, 2H). Mass (M+H) is 277 and 279.

1. customevaporated to dryness
2. customThe residue was crystallized in ethanol/water
3. filtrationPure crystal product was filtered
4. customdried under vacuum