Acetic Anhydride → 6-Iodo-2-methyl-4H-3,1-benzoxazin-4-one

HRID 13650

Reaction equation

HRID 13650 reaction equation
[NH2:1][C:2]1[CH:10]=[CH:9][C:8]([I:11])=[CH:7][C:3]=1[C:4]([OH:6])=[O:5].[C:12](OC(=O)C)(=O)[CH3:13]>>[I:11][C:8]1[CH:9]=[CH:10][C:2]2[N:1]=[C:12]([CH3:13])[O:5][C:4](=[O:6])[C:3]=2[CH:7]=1

Participants

3

Reactant 2

HCID 7918Acetic AnhydrideHCID 72911Benzoic acid, 2-amino-5-iodo-

Product 1

HCID 9153906-Iodo-2-methyl-4H-3,1-benzoxazin-4-oneYield 90%

Procedure

2-Amino-5-iodobenzoic acid (25.4 g, 96.6 mmol) was added in portions to cold acetic anhydride (100 mL). The suspension was first stirred without cooling, then the resulting thick precipitate was heated at reflux for 1 h (red solution). The product crystallized spontaneously upon cooling. After stirring in ice for 30 min, the crystals were filtered off and washed twice with heptane. The crystals were thoroughly dried at 0.1 mbar/50° C. One obtained 25.1 g (90%) of beige crystals. MS: m/z=287 (M).

Workup

  1. temperaturewithout cooling
  2. temperaturethe resulting thick precipitate was heated
  3. temperatureat reflux for 1 h (red solution)
  4. customThe product crystallized spontaneously
  5. temperatureupon cooling
  6. stirringAfter stirring in ice for 30 min
  7. filtrationthe crystals were filtered off
  8. washwashed twice with heptane
  9. customThe crystals were thoroughly dried at 0.1 mbar/50° C

Sources & evidence

ORD record
ord-f1525804138841f4a88333612dbe8237
Source dataset
uspto-grants-2010_06
Patent number
US07728142B2

Linked notes

Loading…