Reaktion #57041

Reaktionsgleichung

methanesulphonyl chloride

Resorcinol

hydroxyphenyl acetic acid

borontrifluoride etherate

→

daidzein

Ausbeute 44.0%

Lösungsmittel

Et2O Hexane

Et2O Hexane

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe resulting mixture was cooled down at room temperature
2. 2
   workup.ADDITIONN,N-dimthylformamide (46.2 mL) was added dropwise
3. 3
   TemperaturThe mixture was again heated up at 50° C. for 30 minutes
4. 4
   TemperaturAfter cooling down at room temperature
5. 5
   FiltrationThe precipitate was filtered
6. 6
   SonstigeThe filtrate was collected
7. 7
   Sonstigedried
8. 8
   SonstigeThe cure product was recrystallised in 94% ethanol (aq)

Vorschrift

Resorcinol (29 mmol) and 4 hydroxyphenyl acetic acid (29 mmol) were dissolved into freshly distilled borontrifluoride etherate (20 mol eq) under nitrogen. The resulting mixture was stirred and heated at 70° C. for overnight. The reaction was monitored by TLC (80% Et2O/Hexane). The resulting mixture was cooled down at room temperature, then N,N-dimthylformamide (46.2 mL) was added dropwise. The mixture was again heated up at 50° C. for 30 minutes, then methanesulphonyl chloride (7 mL in 10 mL DMF) was added dropwise and the resulting mixture was heated at 60-70° C. until LC (80% Et2O/Hexane) shown that the reaction was almost finished, about 10 hours. After cooling down at room temperature, the mixture was poured into 400 mL ice-cold water. The precipitate was filtered. The filtrate was collected and dried. The cure product was recrystallised in 94% ethanol (aq) and gave a quite pure daidzein (3 g) in 44% yield.

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