Reaktion #62224

Reaktionsgleichung

water

30

2-Methoxy-6,7,8,9-tetrahydro-benzocyclohepten-5-one

3,4,5-trimethoxybromobenzene

n-Butyllithium

→

32

Ausbeute 49.6%

2-Methoxy-5-(3,4,5-trimethoxyphenyl)-6,7,8,9-tetrahydro-benzocyclohepten-5-ol

Ausbeute 49.6%

Lösungsmittel

ether

ether

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigewas brought to −78° C.
2. 2
   workup.ADDITIONwas added dropwise
3. 3
   workup.ADDITIONwas added dropwise
4. 4
   workup.STIRRINGto stir until the temperature
5. 5
   Temperaturwarmed up to room temperature
6. 6
   Extraktionthe product was extracted with ether (3×50)
7. 7
   Trocknenwere dried over anhydrous magnesium sulfate
8. 8
   Filtrationfiltered
9. 9
   Sonstigeevaporated under reduced pressure
10. 10
    SonstigePurification by column chromatography (silica gel, 20:80 EtOAc:Hexanes)

Vorschrift

200 mL of anhydrous ether was, added to 3,4,5-trimethoxybromobenzene (1.23 g, 4.97 mmol) in a 500 mL round bottom flask under nitrogen. The temperature of the reaction mixture was brought to −78° C. n-Butyllithium (4.5 mL, 11.25 mmol) was added dropwise. The reaction mixture was then stirred until the temperature was raised gradually to −30° C. 30 (0.86 g, 4.5 mmol) dissolved in 25 mL of dry ether was added dropwise and the reaction mixture was allowed to stir until the temperature warmed up to room temperature. 25 mL of water was added and the product was extracted with ether (3×50), combined organic phases were dried over anhydrous magnesium sulfate, filtered and evaporated under reduced pressure. Purification by column chromatography (silica gel, 20:80 EtOAc:Hexanes) yielded 800 mg (49%) of 32 as pale yellow oil Rf: 0.16 (30:70, EtOAc:Hexanes).

Quelle