Reaktion #340483

Reaktionsgleichung

3-fluoro-4,5-dihydroxybenzaldehyde

cesium carbonate

1,2 Dibromoethane

→

8-fluoro-2,3-dihydro-1,4-benzodioxine-6-carbaldehyde

Ausbeute 87.0%

Lösungsmittel

DMF

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigereaction mixture
2. 2
   WaschenThe mixture was washed with water (2×50 ml), 10% aqueous citric acid (50 ml), brine (50 ml)
3. 3
   Trocknendried over sodium sulfate
4. 4
   Sonstigeevaporated to dryness

Vorschrift

3-fluoro-4,5-dihydroxybenzaldehyde (0.9 g; 5.7 mmol) and cesium carbonate (4.6 g; 14.2 mmol) were stirred in DMF (15 ml) at room temperature for 15 min. 1,2 Dibromoethane (638 μl; 7.4 mmol) was added and reaction mixture was stirred at 80° C. for 2.5 h and then diluted with dichloromethane (100 ml). The mixture was washed with water (2×50 ml), 10% aqueous citric acid (50 ml), brine (50 ml), dried over sodium sulfate and evaporated to dryness to yield 8-fluoro-2,3-dihydro-1,4-benzodioxine-6-carbaldehyde (0.9 g; 87% yield). 1H NMR (400 MHz, CD3OD) δ 9.74 (d, 1H), 7.25 (m, 2H), 4.37 (m, 4H).

Quelle