Reaktion #322284

Reaktionsgleichung

3,4-dibromothiophene

n-butyllithium

N-methyl-N-methoxypropionamide

→

tan solid

Ausbeute 38.3%

3-bromo-4-(1-oxopropyl)thiophene

Ausbeute 38.3%

Lösungsmittel

ether

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeat -78° C.
2. 2
   workup.STIRRINGthe reaction was stirred for 1 hour
3. 3
   SonstigeThe reaction was quenched with satd NH4Cl
4. 4
   workup.ADDITIONthe mixture was diluted with ether
5. 5
   SonstigeThe ether layer was separated
6. 6
   Waschenwashed with water and brine
7. 7
   Trocknendried over MgSO4
8. 8
   Einengenconcentrated
9. 9
   SonstigeThe residue was triturated with hexanes
10. 10
    Filtrationthe mixture was filtered
11. 11
    SonstigeThe solvent was removed

Vorschrift

A solution of 3,4-dibromothiophene (6.0 g, 24.8 mmol) in 10 mL of ether was cooled to -78° C. and trated with n-butyllithium (9.92 mL, 2.5M solution in hexanes, 24.8 mmol). While holding the temperature at -78° C., the reaction was stirred for 15 minutes, then 2.9 g (24.8 mmol) of N-methyl-N-methoxypropionamide was added and the reaction was stirred for 1 hour. The reaction was quenched with satd NH4Cl, and the mixture was diluted with ether. The ether layer was separated, washed with water and brine, dried over MgSO4 and concentrated. The residue was triturated with hexanes, and the mixture was filtered. The solvent was removed to give 2.08 g of a tan solid. MS 236, 238 (M+NH4)+. NMR (CDCl3) δ:7.99 (d, J=3 Hz, 1H), 7.32 (d, J=3 Hz, 1H), 2.98 (q, J=7 Hz, 2H), 1.21 (t, J=7 Hz, 3H).

Quelle