Ethylene Glycol → 2-(4-Bromothiophen-2-yl)-1,3-dioxolane

HRID 900989Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 900989
[Br:1][C:2]1[CH:3]=[C:4]([CH:7]=[O:8])[S:5][CH:6]=1.[CH2:9](O)[CH2:10][OH:11]>C1(C)C=CC=CC=1.C1(C)C=CC(S(O)(=O)=O)=CC=1>[Br:1][C:2]1[CH:3]=[C:4]([CH:7]2[O:11][CH2:10][CH2:9][O:8]2)[S:5][CH:6]=1

Komponenten

5

Edukt 2

HCID 174Ethylene GlycolHCID 877924-Bromothiophene-2-carbaldehyde

Produkt 1

HCID 38572552-(4-Bromothiophen-2-yl)-1,3-dioxolaneAusbeute 98 %

Reagenzien, Katalysatoren, Lösungsmittel 2

HCID 6101p-Toluenesulfonic acidKatalysatorHCID 1140TolueneLösungsmittel

Versuchsvorschrift

A mixture of 4-bromo-thiophene-2-carbaldehyde (175 g, 916 mmol), ethylene glycol (71.1 g, 1.15 mol) and p-toluenesulfonic acid (0.19 g, 1.0 mmol) in toluene (250 mL) is heated to reflux for 7 h using a Dean-Stark apparatus. After cooling, the solution is washed with aq NaHCO3, dried over Na2SO4, filtered and concentrated in vacuo. The residue is distilled to give 2-(4-bromo-thiophen-2-yl)-[1,3]dioxolane (210.6 g, 98%) as a colorless liquid: bp 133-143/11-14 mBar; 1H NMR (CDCl3, 300 MHz) δ 7.21 (s, 1 H), 7.04 (s, 1 H), 6.04 (s, 1 H), 3.95-4.18 (m, 4 H).

Aufarbeitung

  1. temperatureis heated
  2. temperatureto reflux for 7 h
  3. temperatureAfter cooling
  4. washthe solution is washed with aq NaHCO3
  5. dry with materialdried over Na2SO4
  6. filtrationfiltered
  7. concentrationconcentrated in vacuo
  8. distillationThe residue is distilled

Quellen und Nachweise

ORD-Eintrag
ord-3ef4551a5af34ca18169c18ad9c958ae
Quelldatensatz
uspto-grants-2008_04
Patentnummer
US07361671B2

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