Reaktion #80448

Reaktionsgleichung

lithium diisopropylamide

iodine

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

→

2-iodo-5-[2-{3-pyridyl}ethenyl]furan

Ausbeute 67.3%

Lösungsmittel

THF

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe cold reaction mixture
2. 2
   SonstigeThe ice bath was removed
3. 3
   workup.STIRRINGto stir at ambient temperature overnight
4. 4
   workup.ADDITIONSaturated NH4Cl was added
5. 5
   workup.ADDITIONthe mixture diluted with ether
6. 6
   WaschenThe organic layer was washed with brine
7. 7
   Trocknendried (MgSO4)
8. 8
   Einengenconcentrated in vacuo
9. 9
   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 2-[2-{3-pyridyl}ethenyl]furan (0.95 g, 5.5 mmol), prepared as in step 4, in THF (25 mL) was added lithium diisopropylamide (4 mL, 6 mmol, 1.5M in hexanes). The cold reaction mixture was stirred 1 hour, followed by the addition of a THF (3 mL) solution of iodine (1.39 g, 5.5 mmol). The ice bath was removed and the reaction mixture allowed to stir at ambient temperature overnight. Saturated NH4Cl was added and the mixture 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-iodo-5-[2-{3-pyridyl}ethenyl]furan.

Quelle