Reaktion #742119

Reaktionsgleichung

5-trimethylsilyl-3-furaldehyde

tert-Butyl lithium

2-(5-bromopentyl)pyridine

acetic anhydride

→

4-[1-Acetoxy-6-(2-pyridyl)hexyl]-2-trimethylsilylfuran

Lösungsmittel

tetrahydrofuran

pentane

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigequenched with water (after 22 hours)
2. 2
   ExtraktionExtraction (ethyl ether) and evaporation of the
3. 3
   Trocknendried (magnesium sulphate)
4. 4
   Sonstigeextracts gave an oil, which
5. 5
   Sonstigechromatographed on silica using 40% ethyl acetate/hexane
6. 6
   SonstigeFractions with Rf of about 0.25 on evaporation
7. 7
   Sonstigegave the title silyfuran as a light brown oil

Vorschrift

tert-Butyl lithium (a 1.7M solution in pentane; 2.4 ml, 4.14 mmol) was added dropwise to a solution of 2-(5-bromopentyl)pyridine (472.3 mg, 2.07 mmol) in tetrahydrofuran (7 ml) at -78° under argon. After 1 hour, a solution of 5-trimethylsilyl-3-furaldehyde (348 mg, 2.07 mmol) in tetrahydrofuran (1 ml) was added, followed by acetic anhydride (0.59 ml, 6.21 mmol) after 2 hours. The mixture was allowed to warm to room temperature and quenched with water (after 22 hours). Extraction (ethyl ether) and evaporation of the dried (magnesium sulphate) extracts gave an oil, which was flash chromatographed on silica using 40% ethyl acetate/hexane. Fractions with Rf of about 0.25 on evaporation gave the title silyfuran as a light brown oil.

Quelle