Reaktion #2667

Reaktionsgleichung

5-iodo vanillin

boron tribromide

→

expected product

Ausbeute 66.2%

3-iodo-4,5-dihydroxy benzaldehyde

Ausbeute 66.2%

Lösungsmittel

dichloromethane

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Einengenwas then concentrated
2. 2
   Temperaturcooled to 0° C.
3. 3
   SonstigeThe crystallized product was separated out
4. 4
   Waschenwashed with water
5. 5
   Sonstigedried
6. 6
   Sonstigecrystallized from an isopropanol

Vorschrift

37.2 g of 5-iodo vanillin (commercial) and 360 ml of dichloromethane were mixed together under nitrogen and the mixture was cooled to 0° C. 135 ml of a molar solution of boron tribromide in dichloromethane were added and the mixture stood for 16 hours at ambient temperature and was then concentrated, cooled to 0° C. and acidified. The crystallized product was separated out, washed with water, dried and crystallized from an isopropanol--water mixture (1-2 by volume) to obtain 23.4 g of the expected product.

Quelle