Reaktion #731334

Reaktionsgleichung

3-(3,4-Dimethoxy-phenyl)-7-hydroxy-8-methylchromen-4-one

Pyridine

acetic anhydride

→

7-acetoxy-3-(3,4-dimethoxyphenyl)-8-methylchromen-4-one

Ausbeute 42.0%

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe reaction mixture was heated
2. 2
   Temperaturto reflux for 1 hour
3. 3
   Sonstigeto produce a crystalline solid within the reaction mixture
4. 4
   FiltrationThis was filtered
5. 5
   Waschenthe solid was washed with the filtrate and additional water (500 mL)
6. 6
   Sonstigeto yield a brown solid
7. 7
   WaschenFurther washing with ethanol
8. 8
   Sonstigeproduced a white crystalline solid
9. 9
   SonstigeThe solid was dried overnight in a desiccator

Vorschrift

3-(3,4-Dimethoxy-phenyl)-7-hydroxy-8-methylchromen-4-one (94.8 g) was suspended in acetic anhydride (450 mL) under a nitrogen atmosphere. Pyridine (23 mL) was added and the reaction mixture was heated to reflux for 1 hour. The pot was cooled overnight at −18° C. to produce a crystalline solid within the reaction mixture. This was filtered and the solid was washed with the filtrate and additional water (500 mL) to yield a brown solid. Further washing with ethanol produced a white crystalline solid. The solid was dried overnight in a desiccator to yield 7-acetoxy-3-(3,4-dimethoxyphenyl)-8-methylchromen-4-one (44.7 g, 42%).

Quelle