Réaction #1846

Équation de réaction

4-bromoanisole

Magnesium

iodine

THF

1,2-dibromoethane

→

Anisylmagnesium Bromide

Conditions de réaction

Traitement

1. 1
   Températureat reflux for 15 min
2. 2
   workup.STIRRINGstirring
3. 3
   AutreAfter an exothermic reaction
4. 4
   workup.STIRRINGstirring
5. 5
   Autrewas accompanied by a rise in temperature to 35° C
6. 6
   TempératureThe mixture was cooled to 20° C.
7. 7
   Températurewith cooling
8. 8
   workup.STIRRINGStirring
9. 9
   workup.ADDITIONafter the addition

Mode opératoire

Magnesium (36 g, 1.5 mol), iodine (a few crystals) and THF (1 L) were heated under nitrogen, with stirring, at reflux for 15 min. The mixture was cooled to 20° C., stirring stopped, and 1,2-dibromoethane (2.5 ml) added. After an exothermic reaction was observed (a few min) stirring was restarted which was accompanied by a rise in temperature to 35° C. The mixture was cooled to 20° C. and 4-bromoanisole slowly added over 1 h at 14°-18° C. with cooling. Stirring was continued for 10 min after the addition was complete.

Source