Reaction #1802003

Reaction equation

2-ethylbenzonitrile

bromine

→

title compound

5-Bromo-2-ethylbenzonitrile

Conditions

Workup

1. 1
   workup.ADDITIONare added dropwise at 55° C.
2. 2
   workup.ADDITIONadd vigorous
3. 3
   OtherThe temperature is kept at 45-50° C., by means of an ice bath
4. 4
   workup.ADDITIONAfter the addition
5. 5
   Otherthe ice bath is removed
6. 6
   workup.STIRRINGthe mixture is stirred at 50° C. for 20 hours
7. 7
   workup.ADDITION300 ml of methanol are added to the reaction mixture
8. 8
   workup.STIRRINGwhile stirring
9. 9
   Filtrationthe suspension is clarified by filtration through Hyflow
10. 10
    OtherThe filtrate is evaporated
11. 11
    Otherthe residue is partitioned between 100 ml of ethyl acetate and 50 ml of saturated sodium bicarbonate solution
12. 12
    DryingThe organic phase is dried with sodium sulphate
13. 13
    Filtrationfiltered
14. 14
    Otherevaporated

Procedure

9.74 ml of 2-ethylbenzonitrile are added dropwise to 100 g of Na-X zeolite (Linde 13X, STREM) with vigorous stirring. After the exothermic reaction, 5.6 ml of bromine are added dropwise at 55° C., add vigorous stirring of the mixture is continued. The temperature is kept at 45-50° C., by means of an ice bath. After the addition is complete, the ice bath is removed, and the mixture is stirred at 50° C. for 20 hours. 300 ml of methanol are added to the reaction mixture while stirring and the suspension is clarified by filtration through Hyflow. The filtrate is evaporated and the residue is partitioned between 100 ml of ethyl acetate and 50 ml of saturated sodium bicarbonate solution. The organic phase is dried with sodium sulphate, filtered and evaporated. The title compound is obtained as a beige crystalline solid from the residue by flash chromatography. Rt=4.87.

Source