反应详情

1,5-Bis(4-hydroxy-3-methoxyphenyl)-1, 4-pentadien-3-one (20a, 0.32 g, 1.0 mmol) was dissolved in acetic anhydride (21, 7.00 ml, 74.1 mmol) and stirred for 5 min at room temperature. Pyridine (0.70 ml, 8.7 mmol) was added and the mixture stirred for 30 min at 100° C. The resulting mixture was poured into water, extracted with ethyl acetate, washed with saturated sodium chloride, dried over magnesium sulfate, filtered and evaporated to afford a solid. The crude solid was recrystallized from tetrahydrofuran/hexane to give 0.36 g (88%) of a yellow solid: mp 179-180° C. [expected mp 150° C.]; 1H NMR: δ 2.31 (s, 6H), 3.87 (s, 6H), 6.98 (d, 2H, J=15.9 Hz), 7.06 (d, 2H, J=8.1 Hz), 7.18 (m, 4H), 7.67 (d, 2H, J=15.9 Hz); 13C NMR: δ 20.7, 56.0, 111.7, 121.4, 123.3, 125.5, 133.7, 141.6, 142.6, 151.4, 168.5, 188.3; Exact mass calcd for C23H22O7: 410.1366, observed (M+H) 411.1444.

1. stirringthe mixture stirred for 30 min at 100° C
2. extractionextracted with ethyl acetate
3. washwashed with saturated sodium chloride
4. dry with materialdried over magnesium sulfate
5. filtrationfiltered
6. customevaporated
7. customto afford a solid
8. customThe crude solid was recrystallized from tetrahydrofuran/hexane