Reaktion #5722

Reaktionsgleichung

Meldrum's acid

pyridine

stearic acid chloride

→

methyl-3-oxoeicosanoate

Lösungsmittel

methylene chloride

Reaktionsbedingungen

Aufarbeitung

1. 1
   Waschenthe reaction mixture was washed with 4N hydrochloric acid
2. 2
   Extraktionthe aqueous phase was extracted with methylene chloride
3. 3
   Trocknenthe methylene chloride phase was dried
4. 4
   Einengenconcentrated
5. 5
   workup.STIRRINGstirred
6. 6
   Temperaturunder reflux
7. 7
   TemperaturAfter cooling
8. 8
   Filtrationthe precipitated crystals were filtered off
9. 9
   workup.DISSOLUTIONdissolved in methylene chloride
10. 10
    Sonstigechromatographed on silica gel with methylene chloride

Vorschrift

To a solution of 117 g of Meldrum's acid and 131 ml of pyridine in 1.5 1 of methylene chloride, 270 ml of stearic acid chloride were added dropwise at a maximum temperature of 15° C. After stirring, the reaction mixture was washed with 4N hydrochloric acid, the aqueous phase was extracted with methylene chloride, the methylene chloride phase was dried and concentrated. The residue was taken up in methanol and stirred under reflux. After cooling, the precipitated crystals were filtered off, dissolved in methylene chloride and chromatographed on silica gel with methylene chloride to give 175 g of methyl-3-oxoeicosanoate, m.p. 52°-54° C.

Quelle