Hydrogen Bromide → 4-bromophthalonitrile

HRID 1890406Notes

Reaction equation

HRID 1890406 reaction equation
N[C:2]1[CH:3]=[C:4]([C:10]#[N:11])[C:5](=[CH:8][CH:9]=1)[C:6]#[N:7].O.N([O-])=O.[Na+].C(Cl)Cl.[BrH:20]>>[Br:20][C:2]1[CH:3]=[C:4]([C:10]#[N:11])[C:5](=[CH:8][CH:9]=1)[C:6]#[N:7]

Participants

6

Reactant 5

HCID 260Hydrogen Bromide2×HCID 962WaterHCID 6344DichloromethaneHCID 925291,2-Benzenedicarbonitrile, 4-amino-2×HCID 23668193Sodium Nitrite

Product 1

HCID 113562234-bromophthalonitrile

Conditions

Temperature
-10 °C

Procedure

Compound 4 (24 g, 0.17 mol) was suspended in a stirring solution of 100 ml HBr (48%) and 100 ml of H2O cooled to −10° C. Sodium nitrite (14 g, 0.20 mol) was dissolved in ice water and added dropwise to the solution of 4-aminophthalonitrile. The exothermic reaction was carefully monitored and kept under 0° C. After 2 hours of stirring, the solution was added dropwise to a solution of Cu(I)Br (27 g, 0.18 mol) in 100 ml of HBr (48%) at −3° C. and stirred at 0° C. for 2 hours. To minimize foaming as well as increase the yield, methylene chloride was added to the solution and the reaction was allowed to proceed overnight for at least 24 hours. The organic layer was removed, and the aqueous layer was also extracted with toluene. The combined organic layers were washed with water, Na2S2O3 (saturated aqueous solution), water, brine, water, dried over MgSO4 and evaporated under reduced pressure. 25 g of an orange product were collected (73%). 1H NMR (CDCl3) δ: 7.99 (d, 1H), 7.94-7.91 (dd, 1H), 7.72-7.70 (d, 1H).6 13C{1H}NMR (CDCl3) 136.68, 136.42, 134.44, 128.19, 117.39, 114.76, 114.65, 114.04 ppm.

Workup

  1. customThe exothermic reaction
  2. customkept under 0° C
  3. stirringstirred at 0° C. for 2 hours
  4. additionwas added to the solution
  5. waitto proceed overnight for at least 24 hours
  6. customThe organic layer was removed
  7. extractionthe aqueous layer was also extracted with toluene
  8. washThe combined organic layers were washed with water, Na2S2O3 (saturated aqueous solution), water, brine, water
  9. dry with materialdried over MgSO4
  10. customevaporated under reduced pressure
  11. custom25 g of an orange product were collected (73%)

Sources & evidence

ORD record
ord-de316d9a8391495ba7894a58ffbf7874
Source dataset
uspto-grants-2013_08
Patent number
US08507153B2

Reaction notes

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