Barium hydroxide, octahydrate → 6-(4-Toluoyl)pyridine-2-sulphonic acid

HRID 2308615Notes

Reaction equation

HRID 2308615 reaction equation
[C:1]1([CH3:16])[CH:6]=[CH:5][C:4]([C:7]([C:9]2[N:14]=[C:13]([SH:15])[CH:12]=[CH:11][CH:10]=2)=[O:8])=[CH:3][CH:2]=1.[OH2:17].[OH2:18].[OH2:19].O.O.O.O.O.[OH-].[Ba+2].[OH-]>O>[C:1]1([CH3:16])[CH:2]=[CH:3][C:4]([C:7]([C:9]2[N:14]=[C:13]([S:15]([OH:19])(=[O:18])=[O:17])[CH:12]=[CH:11][CH:10]=2)=[O:8])=[CH:5][CH:6]=1

Participants

4

Reactant 2

HCID 17749109Barium hydroxide, octahydrateHCID 178425677HCID 178425677, compound

Product 1

HCID 201875136-(4-Toluoyl)pyridine-2-sulphonic acidYield 80.6%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

This thiol (9.16 g) was dissolved in a solution of barium hydroxide octahydrate (12.62 g) in water (250 ml) and the solution filtered. To the stirred and ice-cooled solution was then added dropwise 30% aqueous hydrogen peroxide (14.0 ml). After allowing to warm to room-temperature the mixture was heated on the steam bath for one hour with stirring. The resultant solution was filtered hot and then allowed to cool whereupon the barium salt of the sulphonic acid crystallised from solution. To the suspension of the barium salt was added with stirring 1.0N aqueous sulphuric acid (40 ml) and the resultant mixture heated on the steam bath for 15 minutes and then allowed to cool. The precipitate of barium sulphate was filtered off and the filtrate concentration to dryness in vacuo and the residue treated with ethanol and reconcentrated to dryness. Trituration with ethanol, filtration and washing with acetone gave 6-(4-toluoyl)pyridine-2-sulphonic acid (8.93 g) as a yellow solid. M.p.>300°.

Workup

  1. filtrationthe solution filtered
  2. temperatureice-cooled solution
  3. additionwas then added dropwise 30% aqueous hydrogen peroxide (14.0 ml)
  4. temperatureto warm to room-temperature the mixture
  5. temperaturewas heated on the steam bath for one hour
  6. stirringwith stirring
  7. filtrationThe resultant solution was filtered hot
  8. temperatureto cool whereupon the barium salt of the sulphonic acid
  9. customcrystallised from solution
  10. additionTo the suspension of the barium salt
  11. additionwas added
  12. stirringwith stirring 1.0N aqueous sulphuric acid (40 ml)
  13. temperaturethe resultant mixture heated on the steam bath for 15 minutes
  14. temperatureto cool
  15. filtrationThe precipitate of barium sulphate was filtered off
  16. concentrationthe filtrate concentration to dryness in vacuo
  17. additionthe residue treated with ethanol
  18. filtrationTrituration with ethanol, filtration
  19. washwashing with acetone

Sources & evidence

ORD record
ord-1f01315a525b49529f1338f44e4bb7d0
Source dataset
uspto-grants-1987_09
Patent number
US04690933

Reaction notes

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