Hydrogen Bromide → HCID 18927059, compound

HRID 1600393Notes

Reaction equation

HRID 1600393 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([Cl:8])=[CH:4][C:3]=1[CH3:9].ClC(Cl)C.[Br:14]Br.Br>[Fe]>[Cl:8][C:5]1[C:6]([Br:14])=[CH:7][C:2]([Br:1])=[C:3]([CH3:9])[CH:4]=1

Participants

6

Reactant 4

HCID 260Hydrogen BromideHCID 63651,1-DichloroethaneHCID 24408BromineHCID 844762-Bromo-5-chlorotoluene

Product 1

HCID 18927059HCID 18927059, compoundYield 81.6%

Reagents, catalysts & solvents 1

HCID 23925IronCatalyst

Procedure

51.4 g (0.25 mol) of 2-bromo-5-chlorotoluene, 25 ml of dichloroethane and 1.5 g of iron powder are introduced into a round-bottomed flask. 40 g (0.25 mol) of bromine are added dropwise at 38°-40° C. with stirring, hydrogen bromide being evolved. The product precipitates out during the addition. The suspension is maintained by adding a further 35 ml of dichloromethane with vigorous agitation. Stirring is continued for 30 minutes after addition of the bromine. The crystal slurry is taken intosolution at room temperature using 20 ml of dichloromethane and the iron powder is filtered off. The organic phase is concentrated by evaporation in a Rotavapor.58 g of 5-chloro-2,4-dibromotoluene is obtained, corresponding to 81.6% of theory relative to 2-bromo-5-chlorotoluene, purity (from gas chromatography): 91%, melting range 91°-95°C.

Workup

  1. customThe product precipitates out during the addition
  2. temperatureThe suspension is maintained
  3. additionby adding a further 35 ml of dichloromethane with vigorous agitation
  4. stirringStirring
  5. additionafter addition of the bromine
  6. customis taken intosolution at room temperature
  7. filtrationthe iron powder is filtered off
  8. concentrationThe organic phase is concentrated by evaporation in a Rotavapor

Sources & evidence

ORD record
ord-adecd33ee18646c6a53c194ca5495d29
Source dataset
uspto-grants-1998_04
Patent number
US05744638

Reaction notes

Loading…