Phosphoric Acid → Quinacridone

HRID 463802Notes

Reaction equation

HRID 463802 reaction equation
P(=O)(O)(O)O.[C:6]1([NH:12][C:13]2[CH:21]=[C:20]([C:22](O)=[O:23])[C:19]([NH:25][C:26]3[CH:31]=[CH:30][CH:29]=[CH:28][CH:27]=3)=[CH:18][C:14]=2[C:15](O)=[O:16])[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1>O>[CH:29]1[CH:30]=[C:31]2[C:22]([C:20]3[C:19]([NH:25][C:26]2=[CH:27][CH:28]=1)=[CH:18][C:14]1[C:15]([C:11]2[C:6]([NH:12][C:13]=1[CH:21]=3)=[CH:7][CH:8]=[CH:9][CH:10]=2)=[O:16])=[O:23]

Participants

4

Reactant 2

HCID 1004Phosphoric AcidHCID 823512,5-Dianilinoterephthalic acid2×

Product 1

HCID 13976QuinacridoneYield 15.3%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
50 °C

Procedure

One hundred and thirty-five ml of polyphosphoric acid and 65 ml of 85% phosphoric acid are mixed in a mechanically stirred beaker and cooled to 50° C. Four grams of 2,5-di(phenylamino)terephthalic acid (DAA) are slowly added in small portions and under agitation by Gifford-Wood homogenizer. Each portion is dissolved before adding another one, checked by dipping a glass rod into the viscous reaction mixture and examining for solid particles clinging to the rod. During this time, the temperature of the reaction mixture is kept at 55° C. or below by cooling with an external water bath. After having dissolved all of the DAA, the solution is heated to 100° C. under stirring and kept at that temperature for 1 hour. The reaction mixture is cooled and poured into 2 l of water under mechanical stirring. The slurry which forms is stirred for 10 minutes and filtered. The filter cake is washed acid-free with water and the water-wet solid reslurried in 600 ml of water. The pH of the slurry is adjusted to 12 with concentrated 50% by weight aqueous NaOH solution under stirring. The slurry is heated to 60° C., held at that temperature for 10 minutes with continued stirring and filtered immediately. The filter cake is washed with water and dried in a vacuum oven at 70°-80° C. to give 0.55 g (15% yield) of quinacridone by-product. Combined filtrate and wash water are stirred and acidified with acetic acid to a pH of 4. The formed precipitate is stirred for 10 minutes, filtered and washed acid-free with water. Vacuum oven drying overnight at 70°-80° C., under slight N2 purge, gives 2.8 g (74% yield) of orange microcrystalline 2-(phenyl)amino-3-carboxy-9(10H) acridinone.

Workup

  1. dissolutionEach portion is dissolved
  2. additionbefore adding another one
  3. customis kept at 55° C. or below
  4. temperatureby cooling with an external water bath
  5. temperaturethe solution is heated to 100° C.
  6. temperatureThe reaction mixture is cooled
  7. stirringThe slurry which forms is stirred for 10 minutes
  8. filtrationfiltered
  9. washThe filter cake is washed acid-free with water
  10. concentrationwith concentrated 50% by weight aqueous NaOH solution
  11. stirringunder stirring
  12. temperatureThe slurry is heated to 60° C.
  13. waitheld at that temperature for 10 minutes
  14. stirringwith continued stirring
  15. filtrationfiltered immediately
  16. washThe filter cake is washed with water
  17. customdried in a vacuum oven at 70°-80° C.

Sources & evidence

ORD record
ord-1db765a506f34a03966edefdee211bea
Source dataset
uspto-grants-1985_10
Patent number
US04544746

Reaction notes

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