反应详情

A stirred solution of 2 (104 mg, 0.3 mmol), N-chlorosuccinimide (80 mg, 0.6 mmol) and concentrated H2SO4 (10 μL) in THF (5 mL) was heated to reflux for 24 h, and then diluted with CHCl3 (50 mL). The reaction mixture was washed with 10% aqueous Na2S2O3 solution (50 mL) and water (2×50 mL), dried over MgSO4, and concentrated in vacuo. The product was purified by column chromatography on silica gel eluting with CHCl3 to afford 37 (56 mg, 49%) as a brown solid. mp 267° C. (decomp.); 1H NMR (CDCl3) δ 8.91 (s, 1H, H4), 7.47 (s, 1H, H6), 6.76-6.91 (m, 3H, H2′+H5′+H6′), 6.08 (AB, 2H, 3′,4′-OCH2O—, Δδ=8.7 Hz, J=1.5 Hz), 5.97 (AB, 2H, 7,8-OCH2O—, Δδ=8.7 Hz, J=1.5 Hz), 5.22 (q, 2H, lactone-CH2—, J=8.7 Hz); MS (EI) m/z 384 [M+2]+, 382 [M]+.

1. temperatureto reflux for 24 h
2. washThe reaction mixture was washed with 10% aqueous Na2S2O3 solution (50 mL) and water (2×50 mL)
3. dry with materialdried over MgSO4
4. concentrationconcentrated in vacuo
5. customThe product was purified by column chromatography on silica gel eluting with CHCl3