Sulfuric Acid → 10-Benzo[1,3]dioxol-5-yl-5-chloro-9H-furo[3',4':6,7]naphtho[1,2-d][1,3]dioxol-7-one

Participants

Reaction Steps

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]+.

Provenance & Evidence