Acetic Anhydride → RAC-5-amino-N-(2,3-diacetoxypropyl)-2,4,6-triiodoisophthalamic acid

HRID 1460939Notes

Reaction equation

HRID 1460939 reaction equation
[OH:1][CH:2]([CH2:20][OH:21])[CH2:3][NH:4][C:5](=[O:19])[C:6]1[C:14]([I:15])=[C:13]([NH2:16])[C:12]([I:17])=[C:8]([C:9]([OH:11])=[O:10])[C:7]=1[I:18].[C:22](OC(=O)C)(=[O:24])[CH3:23].[C:29](OCC)(=[O:31])[CH3:30]>CN(C)C1C=CN=CC=1>[C:22]([O:1][CH:2]([CH2:20][O:21][C:29](=[O:31])[CH3:30])[CH2:3][NH:4][C:5](=[O:19])[C:6]1[C:14]([I:15])=[C:13]([NH2:16])[C:12]([I:17])=[C:8]([C:9]([OH:11])=[O:10])[C:7]=1[I:18])(=[O:24])[CH3:23]

Participants

5

Reactant 3

HCID 7918Acetic AnhydrideHCID 8857Ethyl AcetateHCID 11828334AGN-PC-00GZVS

Product 1

HCID 11767746RAC-5-amino-N-(2,3-diacetoxypropyl)-2,4,6-triiodoisophthalamic acid

Reagents, catalysts & solvents 1

HCID 142844-(Dimethylamino)pyridineCatalyst

Procedure

300 g (0.475 mol) of 5-amino-2,4,6-triiodoisophthalic acid mono-(2,3-dihydroxy-propyl) amide is suspended in 1.4 liter of ethyl acetate, mixed with 178.07 g (1.74 mol) of acetic anhydride and 5.7 g (47.5 mmol) of 4-dimethylaminopyridine and the mixture is heated to boiling. The suspension changes into a solution from which the product quickly crystallizes out in the boiling heat. The acetylation is completed after 1 hour. The excess acetic anhydride is reacted to ethyl acetate by addition of ethanol, cooled to room temperature, the crystallizate is suctioned off, washed with ethyl acetate and dried in a vacuum at 50° C. The yield is 300.2 g (0.42 mol)=88.4% of theory.

Workup

  1. temperaturethe mixture is heated to boiling
  2. customquickly crystallizes out in the
  3. temperatureboiling heat
  4. customThe excess acetic anhydride is reacted to ethyl acetate by addition of ethanol
  5. washwashed with ethyl acetate
  6. customdried in a vacuum at 50° C

Sources & evidence

ORD record
ord-dbf19fe3d6c84dafa90518147269c90a
Source dataset
uspto-grants-1991_12
Patent number
US05073362

Reaction notes

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