Phthalic Acid → N-Isopropylaniline

HRID 1707700Notes

Reaction equation

HRID 1707700 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[C:8](O)(=O)[C:9]1C(=CC=C[CH:17]=1)C(O)=O.[BH4-].[Na+].[OH-].[Na+]>CC(C)=O.O1CCCC1>[CH:9]([NH:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1)([CH3:17])[CH3:8]

Participants

7

Reactant 4

HCID 1017Phthalic AcidHCID 6115AnilineHCID 14798Sodium HydroxideHCID 4311764Sodium borohydride

Product 1

HCID 13032N-Isopropylaniline

Reagents, catalysts & solvents 2

HCID 180AcetoneSolventHCID 8028TetrahydrofuranSolvent

Conditions

Temperature
10 °C

Procedure

N-isopropylaniline is synthesized as follows: A mixture of 233 g. (2.5 moles) of aniline, 5 l. of tetrahydrofuran and 250 ml. of acetone is stirred at 24°-25° C. under nitrogen for 2 hours and coooled to 10° C., 675 g. (4.06 moles) of phthalic acid is added rapidly, the resulting suspension is stirred at 10° C. under nitrogen, and 100 g. (2.64 moles) of powdered 98% sodium borohydride is added over a period of 25 minutes with stirring under nitrogen, during the course of which the temperature rises to 28° C. The reaction mixture is stirred under nitrogen at 28° C. for 15 minutes and at 60°-61° C. for 2 hours, cooled to 25° C. and siphoned portionwise into 2.0 l. of 20% sodium hydroxide solution at a rate such that the temperature does not exceed 20° C. The organic phase is separated, 1.0 kg. of anhydrous potassium carbonate is added, the mixture is stirred at 20°-25° C. for 20 minutes, the solid is removed by filtration and washed twice with 250 ml. portions of tetrahydrofuran, the washings are combined with the filtrate, and the tetrahydrofuran is distilled at 20-100 mm. Hg. and a maximum temperature of 55° C. The resulting residual oil is fractionally distilled through a 35 cm. Vigreux column to obtain the 97.4% pure product (295 g. (84.4%)). B.p. 62°-64° C./1 mm. Hg.

Workup

  1. additionA mixture of 233 g
  2. customcoooled to 10° C.
  3. stirringwith stirring under nitrogen, during the course of which the temperature
  4. customrises to 28° C
  5. stirringThe reaction mixture is stirred under nitrogen at 28° C. for 15 minutes and at 60°-61° C. for 2 hours
  6. temperaturecooled to 25° C.
  7. customdoes not exceed 20° C
  8. customThe organic phase is separated
  9. additionof anhydrous potassium carbonate is added
  10. stirringthe mixture is stirred at 20°-25° C. for 20 minutes
  11. customthe solid is removed by filtration
  12. washwashed twice with 250 ml
  13. distillationthe tetrahydrofuran is distilled at 20-100 mm. Hg
  14. customa maximum temperature of 55° C
  15. distillationThe resulting residual oil is fractionally distilled through a 35 cm

Sources & evidence

ORD record
ord-7fec5edd59a04475abf0fc4e60acb927
Source dataset
uspto-grants-1994_10
Patent number
US05354772

Reaction notes

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