Reaktion #816413

Reaktionsgleichung

3- Formylaminothiophene

lithium diisopropylamine

trimethylsilylchloride

→

2-trimethylsilyl-3-formylaminothiophene

Lösungsmittel

THF

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added
2. 2
   workup.STIRRINGAfter stirring for an additional hour at this temperature the mixture
3. 3
   Temperaturwas slowly warmed to room temperature
4. 4
   workup.STIRRINGstirred for 4 hours
5. 5
   SonstigeQuenching with a saturated solution of ammonium chloride
6. 6
   Extraktionextracting with ethyl acetate
7. 7
   Trocknendrying over sodium sulfate
8. 8
   Sonstigeremoving the solvent

Vorschrift

3- Formylaminothiophene (Bull. Soc. Chim. Fr. 1976,151) (2 g), dissolved in dry THF (20 ml), was dropped into a freshly prepared solution of lithium diisopropylamine (0.035 mol) in THF (35 ml) at −70° C. The solution was warmed to −20° C. and stirred for 30 minutes, then cooled again to −70° C., whereupon trimethylsilylchloride (5 ml) was added. After stirring for an additional hour at this temperature the mixture was slowly warmed to room temperature and stirred for 4 hours. Quenching with a saturated solution of ammonium chloride, extracting with ethyl acetate, drying over sodium sulfate, removing the solvent and applying chromatography on silica gel (hexane:ethyl acetate 2:1) yielded 2-trimethylsilyl-3-formylaminothiophene (1.2 g) (m.p. 74-76° C.).

Quelle