Sulfuric Acid → 3-Hydroxy-2,6-naphthalenedisulfonic acid

HRID 1064211Notes

Reaction equation

HRID 1064211 reaction equation
[OH:1][C:2]1[CH:11]=[C:10]2[C:5]([CH:6]=[CH:7][C:8]([S:12]([OH:15])(=[O:14])=[O:13])=[CH:9]2)=[CH:4][CH:3]=1.[OH:16][S:17](O)(=[O:19])=[O:18]>O>[OH:1][C:2]1[C:3]([S:17]([OH:19])(=[O:18])=[O:16])=[CH:4][C:5]2[C:10]([CH:11]=1)=[CH:9][C:8]([S:12]([OH:15])(=[O:13])=[O:14])=[CH:7][CH:6]=2

Participants

4

Reactant 2

HCID 1118Sulfuric AcidHCID 70897-Hydroxy-2-naphthalenesulfonic acid

Product 1

HCID 119707503-Hydroxy-2,6-naphthalenedisulfonic acidYield 68%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent2×

Conditions

Temperature
115 °C

Procedure

7-Hydroxynaphthalene-2-sulfonic acid (250 g, 1.16 mol) was added in portions to a mixture of concentrated H2SO4 (950 g) and water (50 g). The mixture was stirred at 110-120° C. for 3 hours, cooled to room temperature, added to a mixture of ice and water (5000 ml) and the product precipitated by the addition of sodium chloride. The slurry was warmed to 90° C. to dissolve the product, stirred for 1 hour at this temperature and then allowed to cool. The product was filtered off and the damp product dissolved in water (3000 ml) at pH 10 by the addition of concentrated sodium hydroxide solution. The solution was then filtered to remove a small amount of insoluble material. The pH of the filtrate was lowered to 7 with concentrated HCl and the product precipitated by the addition sodium chloride. The product was filtered off and dried in a vacuum oven to give 117 g of a cream coloured solid (68% yield).

Workup

  1. temperaturecooled to room temperature
  2. customthe product precipitated by the addition of sodium chloride
  3. temperatureThe slurry was warmed to 90° C.
  4. dissolutionto dissolve the product
  5. stirringstirred for 1 hour at this temperature
  6. temperatureto cool
  7. filtrationThe product was filtered off
  8. dissolutionthe damp product dissolved in water (3000 ml) at pH 10 by the addition of concentrated sodium hydroxide solution
  9. filtrationThe solution was then filtered
  10. customto remove a small amount of insoluble material
  11. customthe product precipitated by the addition sodium chloride
  12. filtrationThe product was filtered off
  13. customdried in a vacuum oven
  14. customto give 117 g of a cream

Sources & evidence

ORD record
ord-ad4f754c840545b9910f5bfabbc5d6ad
Source dataset
uspto-grants-2005_11
Patent number
US06969421B2

Reaction notes

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