Ethyl 2-aminobenzoate → 3-(4-Methylphenyl)quinazoline-2,4(1H,3H)-dione

HRID 1735963Notes

Reaction equation

HRID 1735963 reaction equation
[C:1]1([CH3:10])[CH:6]=[CH:5][C:4]([N:7]=[C:8]=[O:9])=[CH:3][CH:2]=1.[C:11](OCC)(=[O:19])[C:12]1[C:13](=[CH:15][CH:16]=[CH:17][CH:18]=1)[NH2:14].C[O-].[Na+]>C1(C)C(C)=CC=CC=1>[C:1]1([CH3:10])[CH:6]=[CH:5][C:4]([N:7]2[C:11](=[O:19])[C:12]3[C:13](=[CH:15][CH:16]=[CH:17][CH:18]=3)[NH:14][C:8]2=[O:9])=[CH:3][CH:2]=1

Participants

5

Reactant 3

HCID 6877Ethyl 2-aminobenzoateHCID 693254-Methylphenyl isocyanateHCID 10942334Sodium Methoxide

Product 1

HCID 4788253-(4-Methylphenyl)quinazoline-2,4(1H,3H)-dioneYield 92.4%

Reagents, catalysts & solvents 1

HCID 7237O-XyleneSolvent2×

Conditions

Temperature
90 °C

Procedure

A solution of p-tolyl isocyanate (133.2 g, 1.00 mol) in xylene (300 ml) is metered at room temperature into a solution of ethyl anthranilate (165.2 g, 1.00 mol) in xylene (600 ml). After addition is complete, the mixture is stirred at 90° C. for 2.5 hours. 18.0 ml of a 30% strength solution of methanolic sodium methoxide (0.10 mol) are metered in and the mixture is stirred at 90° C. for a further 2 hours, ethanol and methanol being distilled off. After cooling, the product is filtered off with suction and washed with 3×75 ml of xylene. The xylene-moist precipitate is treated with dilute hydrochloric acid and the residual xylene is removed by azeotropic distillation. The product is then filtered off with suction, washed with water and dried. 233.0 g of 3-(4-tolyl)-2,4(1H,3H)-quinazolinedione (yield 92.4% of theory) of melting point 267° C. (lit 265° to 266° C.) are obtained.

Workup

  1. additionAfter addition
  2. stirringis stirred at 90° C. for a further 2 hours
  3. distillationethanol and methanol being distilled off
  4. temperatureAfter cooling
  5. filtrationthe product is filtered off with suction
  6. washwashed with 3×75 ml of xylene
  7. additionThe xylene-moist precipitate is treated with dilute hydrochloric acid
  8. customthe residual xylene is removed by azeotropic distillation
  9. filtrationThe product is then filtered off with suction
  10. washwashed with water
  11. customdried

Sources & evidence

ORD record
ord-ca8b6f8e4904455197b654be1c078483
Source dataset
uspto-grants-1996_07
Patent number
US05539114

Reaction notes

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