Reaktion #54651

Reaktionsgleichung

2,3-dihydro-7-methoxy-6-benzofuranol

hydrogen chloride

ether

→

2,3-Dihydro-6-hydroxy-7-methoxy-5-benzofurancarboxaldehyde

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONA mixture of 2.49 g
2. 2
   workup.WAITto stand overnight at room temperature
3. 3
   Einengenthen concentrated in vacuo
4. 4
   workup.ADDITIONthe residue treated with 100 ml
5. 5
   Temperaturof 0.1N HCl for 1 hour at reflux
6. 6
   TemperaturAfter cooling
7. 7
   Extraktionether extraction
8. 8
   Sonstigeprovided the product which
9. 9
   Sonstigewas purified by chromatography over silica gel (E. Merck 60)
10. 10
    Wascheneluting with CHCl3
11. 11
    Sonstigeto yield a colorless solid, m.p. 71°-72°

Vorschrift

A mixture of 2.49 g. (15 mmole) of 2,3-dihydro-7-methoxy-6-benzofuranol, 5.87 g. (50 mmole) zinc cyanide and 100 ml. of dry ether was saturated with hydrogen chloride for 1 hour at 0°, then for 2 hours at room temperature. The mixture was then allowed to stand overnight at room temperature then concentrated in vacuo and the residue treated with 100 ml. of 0.1N HCl for 1 hour at reflux. After cooling, ether extraction provided the product which was purified by chromatography over silica gel (E. Merck 60), eluting with CHCl3, to yield a colorless solid, m.p. 71°-72°.

Quelle