Phosgene → 4-Chloroisatoic anhydride

HRID 635513Notes

Reaction equation

HRID 635513 reaction equation
[Cl:1][C:2]1[CH:3]=[C:4]([NH2:11])[C:5](=[CH:9][CH:10]=1)[C:6]([OH:8])=[O:7].[C:12](Cl)(Cl)=[O:13]>O1CCOCC1.C1(C)C=CC=CC=1>[Cl:1][C:2]1[CH:3]=[C:4]2[NH:11][C:12](=[O:13])[O:8][C:6](=[O:7])[C:5]2=[CH:9][CH:10]=1

Participants

5

Reactant 2

HCID 6371PhosgeneHCID 666462-Amino-4-chlorobenzoic acid

Product 1

HCID 3291054-Chloroisatoic anhydrideYield 76.2%

Reagents, catalysts & solvents 2

HCID 1140TolueneSolventHCID 312751,4-DioxaneSolvent

Procedure

To a mixture of 10.0 g (58.0 mmol) of 4-chloroanthranilic acid in 100 mL of 1,4-dioxane was slowly added 100 mL (193 mmol) of a 1.93 molar solution of phosgene in toluene, at room temperature. The mixture was stirred overnight. The mixture was concentrated to yield a residue which was triturated with ethyl acetate-hexane (1:4), filtered, washed with hexane and dried to afford 8.78 g (76.2%) of the 4-chloroisatoic anhydride as a light brown solid. MS (Cl mode) m/z 198 (M+H, 100%), Cl pattern 200, 35%.

Workup

  1. customat room temperature
  2. concentrationThe mixture was concentrated
  3. customto yield a residue which
  4. customwas triturated with ethyl acetate-hexane (1:4)
  5. filtrationfiltered
  6. washwashed with hexane
  7. customdried

Sources & evidence

ORD record
ord-af21a8ff21644754a3d060d30096b73f
Source dataset
uspto-grants-2001_02
Patent number
US06187923B1

Reaction notes

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