Reaktionsgleichung
[Br:1][C:2]1[C:3]([OH:12])=[C:4]([CH:7]=[C:8]([O:10][CH3:11])[CH:9]=1)[CH:5]=O.Br[CH:14](C(OC)=O)[C:15]([O:17][CH3:18])=[O:16].C(=O)([O-])[O-].[K+].[K+]>C1(C)C=CC=CC=1.[Br-].C([N+](CCCC)(CCCC)CCCC)CCC>[Br:1][C:2]1[C:3]2[O:12][C:14]([C:15]([O:17][CH3:18])=[O:16])=[CH:5][C:4]=2[CH:7]=[C:8]([O:10][CH3:11])[CH:9]=1Komponenten
Edukt 3
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 2
Versuchsvorschrift
To a solution containing 3-Bromo-2-hydroxy-5-methoxy-benzaldehyde (94.7 g, 0.410 mol) and dimethyl bromomalonate (103 g, 0.492 mol) in toluene (1.2 L) was added freshly powdered potassium carbonate (85 g, 0.615 mol) and tetra-n-butylammonium bromide (13.2 g, 0.041 mol). The reaction was heated at reflux under a Dean-Stark trap for 48 h. The reaction was concentrated and the residue dissolved with dichloromethane (−0.5 L) and filtered through Celite, washing with dichloromethane (˜0.5 L). The filtrate was washed with 1 L of 1M sodium hydroxide and water (2×1 L). The organic phase was then passed through a 400 g pad of silica gel washing with dichloromethane (˜1 L) and the filtrate was concentrated to give the desired benzofuran (64 g, 56%) as an orange solid, mp 107–111° C. 1H NMR δ (CDCl3) 7.50 (s, 1H), 7.23 (d, 1H), 7.03 (d, 1H), 3.98 (s, 3H), 3.82 (s, 3H).
Aufarbeitung
- temperatureThe reaction was heated
- temperatureat reflux under a Dean-Stark trap for 48 h
- concentrationThe reaction was concentrated
- dissolutionthe residue dissolved with dichloromethane (−0.5 L)
- filtrationfiltered through Celite
- washwashing with dichloromethane (˜0.5 L)
- washThe filtrate was washed with 1 L of 1M sodium hydroxide and water (2×1 L)
- concentrationthe filtrate was concentrated
Quellen und Nachweise
- ORD-Eintrag
- ord-4168c7d6c6a6492c9e5012519517523b
- Quelldatensatz
- uspto-grants-2006_08
- Patentnummer
- US07094798B1
Verknüpfte Notizen
Wird geladen…