Reaktion #312941

Reaktionsgleichung

2,2-dimethyl-N-pyridin-3-ylpropanamide

TMEDA

lithium

iodine

→

title compound

Ausbeute 38.0%

N-(4-Iodopyridin-3-yl)-2,2-dimethylpropanamide

Ausbeute 38.0%

Lösungsmittel

tetrahydrofuran

diethyl ether

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGstirred for a further 2 hours
2. 2
   TemperaturThe reaction mixture was again cooled to −78° C.
3. 3
   workup.STIRRINGThe resulting slurry was stirred at −78° C. for 2 hours
4. 4
   TemperaturThe mixture was warmed to 0° C.
5. 5
   Sonstigewas quenched with saturated aqueous sodium thiosulfate solution (50 mL)
6. 6
   SonstigeThe phases were separated
7. 7
   Extraktionthe aqueous phase was extracted with dichloromethane (2×30 mL)
8. 8
   TrocknenThe combined organic phase was dried over magnesium sulfate
9. 9
   Einengenconcentrated in vacuo
10. 10
    SonstigePurification of the residue by column chromatography on silica gel
11. 11
    Wascheneluting with pentane

Vorschrift

A solution of 2,2-dimethyl-N-pyridin-3-ylpropanamide [(1 g, 5.61 mmol), J. Org. Chem, 48(20), 3401;1998]in tetrahydrofuran (10 mL) and diethyl ether (30 mL) was cooled to −78° C. and TMEDA (2.1 mL, 14 mmol) and nbutyl lithium (1.6M in hexane, 8.8 mL, 14 mmol,) were added dropwise. The mixture was stirred for 15 minutes and was then warmed to −10° C. and stirred for a further 2 hours. The reaction mixture was again cooled to −78° C. and a solution of iodine (3.56 g, 14 mmol) in tetrahydrofuran (10 mL) was added dropwise. The resulting slurry was stirred at −78° C. for 2 hours. The mixture was warmed to 0° C. and was quenched with saturated aqueous sodium thiosulfate solution (50 mL). The phases were separated and the aqueous phase was extracted with dichloromethane (2×30 mL). The combined organic phase was dried over magnesium sulfate and concentrated in vacuo. Purification of the residue by column chromatography on silica gel, eluting with pentane:ethyl acetate, 50:50 afforded the title compound as a yellow solid in 38% yield, 655 mg.

Quelle