Reaction #1846

Reaction equation

4-bromoanisole

Magnesium

iodine

THF

1,2-dibromoethane

→

Anisylmagnesium Bromide

Conditions

Workup

1. 1
   Temperatureat reflux for 15 min
2. 2
   workup.STIRRINGstirring
3. 3
   OtherAfter an exothermic reaction
4. 4
   workup.STIRRINGstirring
5. 5
   Otherwas accompanied by a rise in temperature to 35° C
6. 6
   TemperatureThe mixture was cooled to 20° C.
7. 7
   Temperaturewith cooling
8. 8
   workup.STIRRINGStirring
9. 9
   workup.ADDITIONafter the addition

Procedure

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