Reaktion #80447

Reaktionsgleichung

n-butyllithium

diethyl 3-pyridylmethylphosphonate

furfuraldehyde

→

2-[2-{3-pyridyl}ethenyl]furan

Ausbeute 49.4%

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe cold reaction mixture
2. 2
   workup.STIRRINGThe reaction was stirred 2 hours at -78° C.
3. 3
   Sonstigethe ice bath removed
4. 4
   workup.STIRRINGto stir at ambient temperature overnight
5. 5
   workup.ADDITIONSaturated NH4Cl was added
6. 6
   workup.ADDITIONthe mixture was diluted with ether
7. 7
   WaschenThe organic layer was washed with brine
8. 8
   Trocknendried (MgSO4)
9. 9
   Einengenconcentrated in vacuo
10. 10
    SonstigeThe resulting residue was purified by column chromatography on silica gel eluting with 40% ethyl acetate-hexanes

Vorschrift

To a stirred -78° C. solution of diethyl 3-pyridylmethylphosphonate (3.0 g, 13 mmol), prepared as in step 3, in THF (50 mL) was added n-butyllithium (25 mL, 55 mmol, 2.5M in hexanes). The cold reaction mixture was stirred 0.5 hours followed by the slow addition of furfuraldehyde (1.24 g, 13 mmol). The reaction was stirred 2 hours at -78° C. and the ice bath removed and allowed to stir at ambient temperature overnight. Saturated NH4Cl was added and the mixture was diluted with ether. The organic layer was washed with brine, dried (MgSO4) and concentrated in vacuo. The resulting residue was purified by column chromatography on silica gel eluting with 40% ethyl acetate-hexanes to afford 1.1 g of 2-[2-{3-pyridyl}ethenyl]furan.

Quelle