Sulfuric Acid → 2-Amino-5-n-propylbenzenesulfonic acid

HRID 344659Notes

Reaction equation

HRID 344659 reaction equation
[CH2:1]([C:4]1[CH:9]=[CH:8][C:7]([NH:10]C(N)=O)=[CH:6][CH:5]=1)[CH2:2][CH3:3].[S:14](=O)(=[O:17])([OH:16])[OH:15]>>[NH2:10][C:7]1[CH:8]=[CH:9][C:4]([CH2:1][CH2:2][CH3:3])=[CH:5][C:6]=1[S:14]([OH:17])(=[O:16])=[O:15]

Participants

3

Reactant 2

HCID 1118Sulfuric AcidHCID 142764214-n-Propylphenylurea

Product 1

HCID 149947812-Amino-5-n-propylbenzenesulfonic acidYield 64.1%

Procedure

A solution of 31.4 g of p-n-propylaniline dissolved in 116 ml of acetic acid and 232 ml of water was added dropwise into 200 ml of a mixed solution comprising 130 g of sodium isocyanate and 900 ml of water, and then stirred in an ice-bath for 30 minutes. The crystals precipitated were filtered, washed with water and dried to give 38.88 g of 4-n-propylphenylurea. After the 4-n-propylphenylurea was added in portions into 107.6 ml of 20% fuming sulfuric acid, the reaction was carried out at 60° C. for 2 hours. Under cooling in an ice-bath, about 400 ml of ice was added into the reaction mixture, followed by heating under reflux for 4 hours. The crystals precipitated by cooling were filtered, washed with water and then dried to give 30.09 g of the above title product (yield: 64.1%). Melting point: 30 261.7°-262.3° C.

Workup

  1. temperatureUnder cooling in an ice-bath
  2. temperatureby heating
  3. temperatureunder reflux for 4 hours
  4. customThe crystals precipitated
  5. temperatureby cooling
  6. filtrationwere filtered
  7. washwashed with water
  8. customdried

Sources & evidence

ORD record
ord-4cfab121bead4d55b5fafd7bd40b7eb7
Source dataset
uspto-grants-1991_10
Patent number
US05053409

Reaction notes

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