Reaktion #78761

Reaktionsgleichung

KF

N-methylpyrrole

TMEDA

n-BuLi

3-bromo-benzaldehyde

Me3SnCl

→

3-(1-methyl-1H-pyrrol-2-yl)benzaldehyde

Ausbeute 40.5%

Lösungsmittel

ethyl acetate

Et2O

dioxane

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe solution was heated
2. 2
   Temperaturto reflux under N2 for 1 h
3. 3
   TemperaturAfter warming to room temperature
4. 4
   TemperaturThe slurry was heated
5. 5
   Temperaturto reflux for 18 h
6. 6
   workup.STIRRINGstirred 15 min
7. 7
   FiltrationThe slurry was filtered through celite
8. 8
   SonstigeThe organic layer was separated
9. 9
   Waschenwashed with brine
10. 10
    Trocknendried (MgSO4)
11. 11
    Sonstigeevaporated to an oil
12. 12
    SonstigePurification by flash chromatography on silica gel eluting with 5% ethyl acetate in hexane

Vorschrift

EX-602A) To solution of N-methylpyrrole (0.97 mL, 11 mmol) in Et2O (20 mL) was added neat TMEDA (1.5 mL, 10 mmol) and 1.6 M n-BuLi in hexanes (6.3 mL, 10 mmol). The solution was heated to reflux under N2 for 1 h and then cooled to −78° C. A 1.0 M solution of Me3SnCl in THF was added over 15 min, and the resulting solution stirred for 30 min at −78° C. After warming to room temperature, 3-bromo-benzaldehyde (0.70 mL, 6.0 mmol), Pd(PPh3)2Cl2 (0.25 g, 0.35 mmol) and dioxane (10 mL) were added. The slurry was heated to reflux for 18 h. The cooled mixture was poured into a mixture of saturated KF and ethyl acetate and stirred 15 min. The slurry was filtered through celite. The organic layer was separated, washed with brine, dried (MgSO4) and evaporated to an oil. Purification by flash chromatography on silica gel eluting with 5% ethyl acetate in hexane gave 0.45 g (24%) of the desired 3-(1-methyl-1H-pyrrol-2-yl)benzaldehyde product as a yellow oil. MS: m/z=186.2 [M+H]+.

Quelle