Iodine → 5,6,7-Trimethoxy-4'-nitroflavone

Participants

Reaction Steps

A mixture of 7a (0.80 g, 2.2 mmol) and iodine (20 mg) in DMSO (5 ml) was refluxed for 1 h, and then carefully poured onto crushed ice. The precipitate was filtered and washed with 20% Na2SO3. Recrystallization of the precipitate from acetone afforded 8 (0.73 g, 93%). 1H NMR (400 MHz, CDCl3) δ 3.91 (s, 3H), 3.97 (s, 3H), 3.98 (s, 3H), 6.74 (s, 1H), 6.82 (s, 1H), 8.03 (d, J=8.8 Hz, 2H), 8.34 (d, J=8.8 Hz, 2H).

Provenance & Evidence