Methanol → 5,12-Dihydro-2,9-dimethylquino(2,3-b)acridine-7,14-dione

HRID 2298712Notes

Reaction equation

HRID 2298712 reaction equation
[CH3:1][C:2]1[CH:28]=[CH:27][C:5]([NH:6][C:7]2[CH:15]=[C:14]([C:16]([OH:18])=O)[C:13]([NH:19][C:20]3[CH:25]=[CH:24][C:23]([CH3:26])=[CH:22][CH:21]=3)=[CH:12][C:8]=2[C:9](O)=[O:10])=[CH:4][CH:3]=1.P(=O)(O)(O)O.CO>O>[CH3:1][C:2]1[CH:28]=[CH:27][C:5]2[NH:6][C:7]3[C:8]([C:9](=[O:10])[C:4]=2[CH:3]=1)=[CH:12][C:13]1[NH:19][C:20]2[CH:25]=[CH:24][C:23]([CH3:26])=[CH:22][C:21]=2[C:16](=[O:18])[C:14]=1[CH:15]=3

Participants

5

Reactant 3

HCID 887MethanolHCID 1004Phosphoric AcidHCID 825242,5-Di-p-toluidinoterephthalic acid

Product 1

HCID 704235,12-Dihydro-2,9-dimethylquino(2,3-b)acridine-7,14-dioneYield 98.8%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
92 °C

Procedure

To 720 g of polyphosphoric acid (117%) heated at 92° C. were added 160 g of 2,5-di(4-methylanilino)terephthalic acid over a period of approximately 65 minutes, the temperature being maintained below 105° C. by adjustment of the addition rate. The reaction mixture was held at 105° C. for five hours and then cooled to 92° C. To this mixture was added 107.9 g of phosphoric acid (75%) dropwise over a period of approximately 30 minutes. The resultant melt was allowed to stir for 15 minutes at 90° C. and then poured slowly into 1120 g of methanol, the temperature being maintained below reflux using a water bath. The slurry was allowed to cool to room temperature and stand for 16 hours. The pigment slurry was heated at reflux for one hour, cooled below 65° C., diluted with water, collected by filtration, and washed with water until free of acid. The resultant presscake was reslurried in water and heated to 45° C. After the slurry was acidified to pH 2.6, an emulsion of 4.7 g of an anionic surfactant, 69.7 g of a petroleum distillate, and 160 g of water was added, and the slurry was stirred for three hours. The resultant slurry was collected by filtration and washed with water. The wet cake can be dried or used as is for specific applications. Here, the wet cake was dried in an oven at 60° C. to give approximately 143 g of 2,9-dimethylquinacridone as a magenta pigment.

Workup

  1. temperaturethe temperature being maintained below 105° C. by adjustment of the addition rate
  2. temperaturethe temperature being maintained
  3. temperaturebelow reflux
  4. temperatureto cool to room temperature
  5. waitstand for 16 hours
  6. temperatureThe pigment slurry was heated
  7. temperatureat reflux for one hour
  8. temperaturecooled below 65° C.
  9. filtrationcollected by filtration
  10. washwashed with water until free of acid
  11. temperatureheated to 45° C
  12. additionan emulsion of 4.7 g of an anionic surfactant, 69.7 g of a petroleum distillate, and 160 g of water was added
  13. stirringthe slurry was stirred for three hours
  14. filtrationThe resultant slurry was collected by filtration
  15. washwashed with water
  16. customThe wet cake can be dried
  17. customHere, the wet cake was dried in an oven at 60° C.

Sources & evidence

ORD record
ord-42a9050584034b8b82294dea40990647
Source dataset
uspto-grants-2002_12
Patent number
US06494948B2

Reaction notes

Loading…