3-Methyl-2-nitrobenzoic acid → HCID 14577205, compound

HRID 1902892Notes

Reaction equation

HRID 1902892 reaction equation
[K].[CH3:2][C:3]1[CH:11]=[CH:10][CH:9]=[C:5]([C:6]([OH:8])=[O:7])[C:4]=1[NH2:12].[N+]([C:16]1[C:24](C)=[CH:23][CH:22]=[CH:21][C:17]=1[C:18]([OH:20])=[O:19])([O-])=O>[Pd].CO.O>[CH3:2][C:3]1[CH:11]=[CH:10][CH:9]=[C:5]([C:6]([OH:8])=[O:7])[C:4]=1[NH:12][C:16]1[CH:24]=[CH:23][CH:22]=[CH:21][C:17]=1[C:18]([OH:20])=[O:19]

Participants

6

Reactant 3

HCID 215753-Methyl-2-nitrobenzoic acidHCID 781012-Amino-3-methylbenzoic acidHCID 5462222Potassium2×

Product 1

HCID 14577205HCID 14577205, compound

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 22242641Methanol--water (1/1)Solvent

Conditions

Temperature
150 °C

Procedure

The potassium salt of 3-methylanthranilic acid was generated by hydrogenation (Palladium-charcoal catalyst) of a solution of the potassium salt of 2-nitro-3-methylbenzoic acid (37.4 gm) in methanol-H2O (1:4 v/v) with following clarification and evaporation to dryness. To this potassium salt were added 2-chlorobenzoic acid (34.5 gm), K2CO3 (34.5 gm), catalytic Cu powder (0.3 gm), CuBr (0.3 gm), N-methyl-2-pyrrolidone (45 ml) and 2-ethoxyethanol (45 ml) and the mixture was heated in an oil bath at 150° C. with stirring for 21/2 hr. Water (1.5 L) was added to the cooled mixture and the whole warmed until the salts had dissolved and crude product was precipitated from the clarified solution by acidiciation with excess HOAc. The product was washed well with boiling water, then dissolved in 5% aqueous Na2CO3 (500 ml) and decolourising charcoal (5 gm) stirred in. To the boiling clarified solution EtOH (500 ml) was added and the mixture acidified by the slow addition of HOAc. The crystalline diacid which separated from the hot solution was collected, washed with boiling water and dried (48.9 gm). Crystallisation from EtOH--H2O provided homogeneous material as colourless needles of mp 258°-259° C.

Workup

  1. customclarification and evaporation to dryness
  2. additionTo this potassium salt were added 2-chlorobenzoic acid (34.5 gm), K2CO3 (34.5 gm), catalytic Cu powder (0.3 gm), CuBr (0.3 gm), N-methyl-2-pyrrolidone (45 ml) and 2-ethoxyethanol (45 ml)
  3. additionWater (1.5 L) was added to the cooled mixture
  4. temperaturethe whole warmed until the salts
  5. dissolutionhad dissolved
  6. customcrude product was precipitated from the clarified solution by acidiciation with excess HOAc
  7. washThe product was washed well with boiling water
  8. dissolutiondissolved in 5% aqueous Na2CO3 (500 ml)
  9. stirringstirred in
  10. additionwas added
  11. additionthe mixture acidified by the slow addition of HOAc
  12. customThe crystalline diacid which separated from the hot solution
  13. customwas collected
  14. washwashed with boiling water
  15. customdried (48.9 gm)
  16. customCrystallisation from EtOH

Sources & evidence

ORD record
ord-57e718c8100f48e588ffbce77dff2b4e
Source dataset
uspto-grants-1982_12
Patent number
US04366318

Reaction notes

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