Reaktion #462050

Reaktionsgleichung

hexamethylphosphoramide

N-Butyllithium

6-bromo-2-naphthol

N,N-dimethylformamide

tertbutyllithium

→

solid

Ausbeute 81.0%

6-Hydroxy-2-naphthaldehyde

Ausbeute 81.0%

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGThe mixture was stirred for 30 min at -78° C
2. 2
   Sonstigetwo hours
3. 3
   Sonstigeat -20° C
4. 4
   workup.STIRRINGAfter stirring for 20 minutes
5. 5
   Sonstigeto come to room temperature
6. 6
   workup.STIRRINGstirred for 1 hour
7. 7
   Sonstigequenched with aqueous ammonium chloride
8. 8
   workup.ADDITIONThe mixture was poured into water
9. 9
   Extraktionextracted with EtOAc
10. 10
    TrocknenThe organic extracts were dried over MgSO4
11. 11
    SonstigeEvaporation and purification by flash chromatography (hexane/EtOAc 3/1 )

Vorschrift

Step a) N-Butyllithium (35.9 mL, 89.7 mmol) was added dropwise to a cold (-78° C.) solution of 6-bromo-2-naphthol (20.0 g, 89.7 mmol) in THF (200 mL). After stirring for 10 minutes, tertbutyllithium (52.76 mL, 89.7 mmol) was added dropwise. The mixture was stirred for 30 min at -78° C, and two hours at -20° C. Then, hexamethylphosphoramide (15.6 mL, 89.7 mmol) was added to the reaction mixture. After stirring for 20 minutes. N,N-dimethylformamide (6.94 mL, 89.7 mmol) was added dropwise. The mixture was allowed to come to room temperature, stirred for 1 hour, and quenched with aqueous ammonium chloride. The mixture was poured into water, acidified with 2N HCL and extracted with EtOAc. The organic extracts were dried over MgSO4. Evaporation and purification by flash chromatography (hexane/EtOAc 3/1 ), gave a yellow solid (12.5 g, 81% yield, m.p. 173°-174 ° C.).

Quelle