反应详情

温度

91.5 °C

A mixture of 2′,4′,6′-trihydroxyacetophenone (20 g, 0.12 mol, dried in the oven at 140° C.) and anhydrous potassium carbonate (50 g, 0.36 mol) in hexamethylphosphoramide (160 mL) was treated with benzyl chloride (30 mL, 0.26 mol), and the suspension heated at 90-93° C., under an argon atmosphere, for 1.5 h. The mixture was then cooled and filtered. The filtrate was added to 300 mL ice-cold water and acidified to pH 4 with 6N hydrochloric acid. The resulting suspension was heated to 70° C. for 1 h, and then cooled at 4° C. for 16 h. The deposited sticky solid was filtered off and washed with water. This solid was air-dried, and recrystallized from boiling methanol/acetone (2:1). Cooling the solution afforded the product 8 as off-white crystals (27.55 g, 66.5% yield). 1H NMR (300 MHz, CDCl3): δ 2.56 (s, 3H, CH3), 5.06 (s, 4H, CH2), 6.10 and 6.16 (2s, 2H, 3′,5′-Ar—H), 7.40 (m, 10H, Ar—H), 14.01 (s, 1H, OH).

1. temperatureThe mixture was then cooled
2. filtrationfiltered
3. additionThe filtrate was added to 300 mL ice-cold water
4. temperatureThe resulting suspension was heated to 70° C. for 1 h
5. temperaturecooled at 4° C. for 16 h
6. filtrationThe deposited sticky solid was filtered off
7. washwashed with water
8. customThis solid was air-dried
9. customrecrystallized
10. temperatureCooling the solution