Ethylene Glycol → 6-Bromo-1,4-dioxaspiro[4.6]undecane

HRID 903

Reaktionsgleichung

Reaktionsgleichung von HRID 903
[Br:1]Br.[C:3]1(=[O:10])[CH2:9][CH2:8][CH2:7][CH2:6][CH2:5][CH2:4]1.[CH2:11]([OH:14])[CH2:12]O.C(=O)(O)[O-].[Na+]>O1CCCC1>[CH2:11]1[O:14][C:3]2([CH2:9][CH2:8][CH2:7][CH2:6][CH2:5][CH:4]2[Br:1])[O:10][CH2:12]1

Komponenten

6

Edukt 4

HCID 174Ethylene GlycolHCID 10400CycloheptanoneHCID 24408BromineHCID 516892Sodium Bicarbonate

Produkt 1

HCID 2882266-Bromo-1,4-dioxaspiro[4.6]undecane

Reagenzien, Katalysatoren, Lösungsmittel 1

HCID 8028TetrahydrofuranLösungsmittel

Versuchsvorschrift

Bromine (44.8 g, 0.28 mol) was added dropwise to a stirred solution of cycloheptanone (28.5 g, 0.25 mol) in a 1:1 solution (300 mL) of ethylene glycol and tetrahydrofuran at room temperature. The mixture was stirred for 5 hours, then poured into aqueous sodium bicarbonate and extracted 3× with diethyl ether. The combined organic layers were washed with brine, dried over sodium sulfate, filtered, and concentrated in vacuo to give 2-bromocycloheptanone ethylene ketal (60 g). A mixture of this crude bromo ketal and a methanolic solution of sodium methoxide (250 mL, 25 wt. % solution) was heated at reflux overnight. The mixture was cooled to ambient temperature, poured into water, and extracted with hexanes. The organic layer was washed with brine, dried over sodium sulfate, filtered, and concentrated in vacuo to afford 2-cycloheptenone ethylene ketal (39 g).

Aufarbeitung

  1. extractionextracted 3× with diethyl ether
  2. washThe combined organic layers were washed with brine
  3. dry with materialdried over sodium sulfate
  4. filtrationfiltered
  5. concentrationconcentrated in vacuo

Quellen und Nachweise

ORD-Eintrag
ord-c3c99a608b9c4984be003f74893691b4
Quelldatensatz
uspto-grants-1998_03
Patentnummer
US05723462

Verknüpfte Notizen

Wird geladen…