Sulfuric Acid → 1-Methyl-3-oxo-1,3-dihydro-2,1-benzoxazole-5,7-dicarboxylic acid

HRID 2049908Notes

Reaction equation

HRID 2049908 reaction equation
[C:1]([C:4]1[CH:5]=[C:6]([C:14]([OH:16])=[O:15])[C:7]2[NH:11][O:10][C:9](=[O:12])[C:8]=2[CH:13]=1)([OH:3])=[O:2].[C:17](=O)([O-])[O-].[Na+].[Na+].COS(OC)(=O)=O.S(=O)(=O)(O)O>>[CH3:17][N:11]1[C:7]2[C:6]([C:14]([OH:16])=[O:15])=[CH:5][C:4]([C:1]([OH:3])=[O:2])=[CH:13][C:8]=2[C:9](=[O:12])[O:10]1

Participants

5

Reactant 4

HCID 1118Sulfuric AcidHCID 6497Dimethyl SulfateHCID 10340Sodium CarbonateHCID 134113503-Oxo-1,3-dihydro-2,1-benzoxazole-5,7-dicarboxylic acid

Product 1

HCID 233458821-Methyl-3-oxo-1,3-dihydro-2,1-benzoxazole-5,7-dicarboxylic acid

Procedure

Crude 1C is dissolved in a slight excess of aqueous sodium carbonate solution and treated with a 10% excess of dimethylsulfate. The reaction is warmed on a steam bath under nitrogen with swirling until the solution becomes homogeneous. The warm reaction mixture is immediately made acidic with concentrated sulfuric acid and allowed to cool. The precipitate which forms on cooling is collected, dried and used directly in the next step. Mass spectrum, m/e 237 (m+).

Workup

  1. temperatureThe reaction is warmed on a steam bath under nitrogen
  2. customThe warm reaction mixture
  3. temperatureto cool
  4. temperatureon cooling
  5. customis collected
  6. customdried

Sources & evidence

ORD record
ord-26b768ae90274fdda60d82289f95956a
Source dataset
uspto-grants-1980_04
Patent number
US04199354

Reaction notes

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