Phosgene → 6-methoxy-2,4-dihydro-1H-3,1-benzoxazine-2,4-dione

HRID 1984836Notes

Reaction equation

HRID 1984836 reaction equation
[NH2:1][C:2]1[CH:10]=[CH:9][C:8]([O:11][CH3:12])=[CH:7][C:3]=1[C:4]([OH:6])=[O:5].[C:13](Cl)(Cl)=[O:14]>C1(C)C=CC=CC=1.C(N(CC)CC)C>[CH3:12][O:11][C:8]1[CH:9]=[CH:10][C:2]2[NH:1][C:13](=[O:14])[O:5][C:4](=[O:6])[C:3]=2[CH:7]=1

Participants

5

Reactant 2

HCID 6371PhosgeneHCID 2779305-Methoxyanthranilic acid

Product 1

HCID 2944796-methoxy-2,4-dihydro-1H-3,1-benzoxazine-2,4-dione

Reagents, catalysts & solvents 2

HCID 1140TolueneSolvent2×HCID 8471TriethylamineSolvent

Procedure

To a suspension of 2-amino-5-methoxy-benzoic acid (8.0 g, 47.8 mmol) in toluene (100 mL) was added a solution of phosgene (20%, 50.0 mL) in toluene and triethyl amine (13.40 mL). The reaction mixture was heated at 80 C. for 1.5 h. The precipitated product was filtered and washed with hexanes and toluene and dried to give 9.00 g of 6-methoxy-1H-benzo[d][1.3]oxazine-2,4-dione as a light brown solid. This was used directly for the next step.

Workup

  1. temperatureThe reaction mixture was heated at 80 C
  2. filtrationThe precipitated product was filtered
  3. washwashed with hexanes and toluene
  4. customdried

Sources & evidence

ORD record
ord-de8a29a61b094041bc44c1078877e5c2
Source dataset
uspto-grants-2009_06
Patent number
US07544699B2

Reaction notes

Loading…