Aniline → 3-Ethoxy-4-hydroxy-azobenzene

HRID 258966Notes

Reaction equation

HRID 258966 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[N:8]([O-])=O.[Na+].C(=O)(O)[O-].[Na+].C([O-])(=O)C.[Na+].[CH2:22]([O:24][C:25]1[CH:30]=[CH:29][CH:28]=[CH:27][C:26]=1[OH:31])[CH3:23]>Cl.O.C(O)C>[CH2:22]([O:24][C:25]1[CH:30]=[C:29]([N:8]=[N:1][C:2]2[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=2)[CH:28]=[CH:27][C:26]=1[OH:31])[CH3:23]

Participants

9

Reactant 5

HCID 6115AnilineHCID 667552-EthoxyphenolHCID 516892Sodium BicarbonateHCID 517045Sodium AcetateHCID 23668193Sodium Nitrite

Product 1

HCID 1356232233-Ethoxy-4-hydroxy-azobenzene

Reagents, catalysts & solvents 3

HCID 313Hydrochloric AcidSolventHCID 702EthanolSolvent2×HCID 962WaterSolvent2×

Procedure

105 g of aniline is dissolved in 290 ml of conc. hydrochloric acid and 350 ml of water, and the solution is cooled to 0° to 5°. At this temperature, an addition is made dropwise, with stirring, of a solution of 84 g of sodium nitrite in 250 ml of water. After 10 minutes' stirring at 0° to 5°, the diazonium salt solution is rendered neutral with 105 g of sodium bicarbonate, and 48 g of sodium acetate (anhydrous) is added. This solution is added dropwise, with stirring, to a solution, cooled to 0° to 5°, of 138 g of 2-ethoxy-phenol in 4300 ml of ethanol, with the temperature being maintained at 0° to 5°. After four hours' stirring at this temperature the greater part of ethanol becomes distilled off. After stirring of the residue with 2000 ml of water, the product is taken up in chloroform. The chloroform layer is subsequently washed with water, dried by means of magnesium sulphate and concentrated by evaporation. There is obtained 3-ethoxy-4-hydroxy-azobenzene, which, as liquid crude product, is used in the next reaction stage.

Workup

  1. additionAt this temperature, an addition
  2. additionis added
  3. additionThis solution is added dropwise
  4. stirringwith stirring, to a solution
  5. temperaturebeing maintained at 0° to 5°
  6. distillationbecomes distilled off
  7. stirringAfter stirring of the residue with 2000 ml of water
  8. washThe chloroform layer is subsequently washed with water
  9. dry with materialdried by means of magnesium sulphate
  10. concentrationconcentrated by evaporation

Sources & evidence

ORD record
ord-02fefb7498a845d1a09628dbce8d3a3e
Source dataset
uspto-grants-1977_07
Patent number
US04035423

Reaction notes

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