Reaktion #323571

ord-d023268cb2704454b9e08b7fc8b542e4

Lösungsmittel

Reaktionsbedingungen

Temperatur
200°CELSIUS
Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    Filtrationthe solution filtered
  2. 2
    Sonstigeto remove
  3. 3
    workup.ADDITIONThis filtered solution was then added to
  4. 4
    Sonstigea similarly prepared
  5. 5
    SonstigeA mildly exothermic reaction
  6. 6
    Temperaturthe mixture was further heated
  7. 7
    SonstigeAt about 145° C., precipitation
  8. 8
    TemperaturThe quantity of brown precipitate increased
  9. 9
    Temperaturwith continued heating
  10. 10
    workup.ADDITIONa further 2 liters of NMP was added
  11. 11
    workup.STIRRINGto facilitate stirring
  12. 12
    Temperaturmaintained for 2 hours, before the mixture
  13. 13
    Temperaturto cool
  14. 14
    SonstigeThe precipitate was collected
  15. 15
    Waschenwashed with NMP
  16. 16
    Sonstigeroughly dried
  17. 17
    Waschenwashed with acetone
  18. 18
    workup.STIRRINGThe material was then stirred well with acetone
  19. 19
    Filtrationfiltered
  20. 20
    Waschenagain washed
  21. 21
    Sonstigebefore being dried overnight at 150° C. under vacuum
  22. 22
    Sonstigethe characteristic imide structure, absorption bands at 1712s and 1765w cm-1

Vorschrift

108 gms (1.0 mole) of p-phenylenediamine was dissolved in 1 liter of warm NMP under a nitrogen atmosphere and the solution filtered to remove suspended particles. This filtered solution was then added to a similarly prepared filtered solution of 928 gms (2.0 moles) of tetrabromophthalic anhydride in 2 liters of warm NMP in the apparatus described in Example 2. A mildly exothermic reaction took place and the mixture was further heated while stirring. At about 145° C., precipitation began. The quantity of brown precipitate increased with continued heating and a further 2 liters of NMP was added to facilitate stirring, the temperature being raised to 200° C. and maintained for 2 hours, before the mixture was allowed to cool. The precipitate was collected, washed with NMP, roughly dried and washed with acetone. The material was then stirred well with acetone, filtered and again washed before being dried overnight at 150° C. under vacuum. The product was a fine, rusty-gold precipitate with a melting point above 500° C. The yield was 486 gms (49%), the infrared spectrum having the characteristic imide structure, absorption bands at 1712s and 1765w cm-1. The compound was insoluble in water, methanol, ether, xylene, dimethyl sulphoxide and dimethyl acetamide.

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US04644066uspto-grants-1987_02