Triphosgene → 6-hydroxy-2,4-dihydro-1H-3,1-benzoxazine-2,4-dione

HRID 1157435Notes

Reaction equation

HRID 1157435 reaction equation
[OH:1][C:2]1[CH:10]=[C:6]([C:7]([OH:9])=[O:8])[C:5]([NH2:11])=[CH:4][CH:3]=1.Cl[C:13](Cl)([O:15]C(=O)OC(Cl)(Cl)Cl)Cl>C1COCC1>[OH:1][C:2]1[CH:3]=[CH:4][C:5]2[NH:11][C:13](=[O:15])[O:8][C:7](=[O:9])[C:6]=2[CH:10]=1

Participants

4

Reactant 2

HCID 94429TriphosgeneHCID 1645925-Hydroxyanthranilic acid

Product 1

HCID 27593156-hydroxy-2,4-dihydro-1H-3,1-benzoxazine-2,4-dioneYield 161.8%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a suspension of 5-hydroxyanthranilic acid (15.3 g, 100 mmol) in THF (400 mL) at 0° C. was added triphosgene (10.1 g, 34 mmol). The resultant mixture was stirred for 5 min at 0° C. and then allowed to warm to room temperature over 6 h. The reaction mixture was cooled at 0° C. overnight and the resultant gray precipitate collected by filtration to afford 6-hydroxy-1H-benzo[d][1,3]oxazine-2,4-dione (9.8 g, 55 mmol, 55%). The filtrate was concentrated in vacuo, the resultant solid triturated with diethyl ether and collected by filtration to afford additional product (7.3 g, 41 mmol, 41%).

Workup

  1. temperatureThe reaction mixture was cooled at 0° C. overnight
  2. filtrationthe resultant gray precipitate collected by filtration

Sources & evidence

ORD record
ord-bf22f3d26929498f8d78f4c5fecd148b
Source dataset
uspto-grants-2010_10
Patent number
US07807686B2

Reaction notes

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