Diethyl Malonate → Diethyl 2,5-dimethylcyclopentane-1,1-dicarboxylate

HRID 1589587

Reaktionsgleichung

Reaktionsgleichung von HRID 1589587
[Na].[C:2]([O:10][CH2:11][CH3:12])(=[O:9])[CH2:3][C:4]([O:6][CH2:7][CH3:8])=[O:5].Br[CH:14]([CH2:16][CH2:17][CH:18](Br)[CH3:19])[CH3:15]>C(O)C>[CH3:19][CH:18]1[CH2:17][CH2:16][CH:14]([CH3:15])[C:3]1([C:4]([O:6][CH2:7][CH3:8])=[O:5])[C:2]([O:10][CH2:11][CH3:12])=[O:9]

Komponenten

5

Edukt 3

HCID 7761Diethyl MalonateHCID 912322,5-DibromohexaneHCID 5360545Sodium

Produkt 1

HCID 14976611Diethyl 2,5-dimethylcyclopentane-1,1-dicarboxylateAusbeute 41,5 %

Reagenzien, Katalysatoren, Lösungsmittel 1

HCID 702EthanolLösungsmittel

Versuchsvorschrift

Sodium metal (16 g, 0.7 mole) was dissolved in absolute ethanol (500 ml) under argon with cooling as necessary to maintain a temperature of <70° C. The solution was cooled and redistilled diethyl malonate (54.3 g, 0.362 mole) was added dropwise, with cooling as necessary, followed by 2,5-dibromohexane (85 g, 0.348 mole) in a single portion. The reaction mixture was stirred overnight at room temperature and then refluxed for 2 hours. The mixture was then concentrated to approximately half the volume under reduced pressure, water (500 ml) added and the mixture extracted with ether (3×200 ml). The combined extracts were dried (Na2SO4), filtered, and evaporated under reduced pressure. The residue was fractionated in vacuo to yield diethyl 2,5-dimethylcyclopentane-1,1-dicarboxylate (35 g), which was homogeneous by GC.

Aufarbeitung

  1. temperaturewith cooling as necessary
  2. temperatureto maintain a temperature of <70° C
  3. temperatureThe solution was cooled
  4. additionwas added dropwise
  5. temperaturewith cooling as necessary,
  6. temperaturerefluxed for 2 hours
  7. concentrationThe mixture was then concentrated to approximately half the volume under reduced pressure, water (500 ml)
  8. additionadded
  9. extractionthe mixture extracted with ether (3×200 ml)
  10. dry with materialThe combined extracts were dried (Na2SO4)
  11. filtrationfiltered
  12. customevaporated under reduced pressure

Quellen und Nachweise

ORD-Eintrag
ord-00fc5a118d284501ad42b2833486b989
Quelldatensatz
uspto-grants-1986_02
Patentnummer
US04571345

Verknüpfte Notizen

Wird geladen…