Ammonium Chloride → 4-(2,6-dibromopyridin-4-yl)sulfonylaniline

HRID 1603553Notes

Reaction equation

HRID 1603553 reaction equation
[Br:1][C:2]1[CH:7]=[C:6]([S:8]([C:11]2[CH:16]=[CH:15][C:14]([N+:17]([O-])=O)=[CH:13][CH:12]=2)(=[O:10])=[O:9])[CH:5]=[C:4]([Br:20])[N:3]=1.[NH4+].[Cl-]>CO.O1CCOCC1.O.[Fe]>[Br:1][C:2]1[CH:7]=[C:6]([S:8]([C:11]2[CH:12]=[CH:13][C:14]([NH2:17])=[CH:15][CH:16]=2)(=[O:9])=[O:10])[CH:5]=[C:4]([Br:20])[N:3]=1

Participants

7

Procedure

22.30 g (0.052 mol) of 2,6-dibromo-4-(4-nitrobenzenesulphonyl)-pyridine were suspended in a mixture of 275 ml of methanol and 275 ml of dioxane, treated with 22.30 g of powdered iron and a solution of 22.30 g of NH4Cl in 550 ml of water and heated at reflux for 1.5 hrs. Then, the organic solvents were distilled off on a rotary evaporator and the residue was diluted with 1.0 l of dichloromethane and suction filtered. The filter material was suspended in a mixture of 250 ml of methanol and 250 ml of dichloromethane in an ultrasound bath, again suction filtered and the filtrate was retained. The first filtrate was separated in a separating funnel and the organic phase was washed with sat. sodium chloride solution, dried over MgSO4, filtered and concentrated together with the second filtrate. The residue was chromatographed on silica gel with dichloromethane. There were obtained 16.6 g (80%) of 4-(2,6-dibromopyridine-4-sulphonyl)-phenylamine as yellowish crystals; m.p.: 196-198° C. (dec.).

Workup

  1. temperatureat reflux for 1.5 hrs
  2. distillationThen, the organic solvents were distilled off on a rotary evaporator
  3. additionthe residue was diluted with 1.0 l of dichloromethane and suction
  4. filtrationfiltered
  5. additionThe filter material was suspended in a mixture of 250 ml of methanol and 250 ml of dichloromethane in an ultrasound bath
  6. filtrationagain suction filtered
  7. customThe first filtrate was separated in a separating funnel
  8. washthe organic phase was washed with sat. sodium chloride solution
  9. dry with materialdried over MgSO4
  10. filtrationfiltered
  11. concentrationconcentrated together with the second filtrate
  12. customThe residue was chromatographed on silica gel with dichloromethane

Sources & evidence

ORD record
ord-300368ec227c40b198f2e8ebc31d38e7
Source dataset
uspto-grants-1999_11
Patent number
US05990105

Reaction notes

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