Water → HCID 21536165, compound

HRID 1077283Notes

Reaction equation

HRID 1077283 reaction equation
[F:1][C:2]1[CH:3]=[C:4]([N:9]([OH:13])[C:10]([NH2:12])=[O:11])[CH:5]=[CH:6][C:7]=1[F:8].Cl[C:15](OCC)=[O:16].O>[OH-].[Na+]>[F:1][C:2]1[CH:3]=[C:4]([N:9]2[C:10](=[O:11])[NH:12][C:15](=[O:16])[O:13]2)[CH:5]=[CH:6][C:7]=1[F:8]

Participants

5

Reactant 3

HCID 962WaterHCID 10928Ethyl chloroformateHCID 21536151HCID 21536151, compound

Product 1

HCID 21536165HCID 21536165, compound

Reagents, catalysts & solvents 1

HCID 14798Sodium HydroxideSolvent

Procedure

1-(3,4-Difluorophenyl)-1-hydroxyurea (0.2 mole) dissolved in aqueous sodium hydroxide (200 ml; 2N) is charged into a glass reaction vessel equipped with a mechanical stirrer and thermometer. The solution is cooled to a temperature of about 10°C and ethyl chloroformate (0.21 mole) is slowly added with stirring. After the addition is completed stirring is continued for a period of about one hour. The reaction mixture is then poured into 2 liters of water. The resulting aqueous solution is then filtered and the filtrate is cooled and acidified with concentrated hydrochloric acid to form a precipitate. The precipitate is recovered by filtration and is dried. The dried product is then dissolved in a methylene chloride-tetrahydrofuran mixture and the resulting solution is dried over anhydrous magnesium sulfate, filtered and stripped of solvent to yield the desired product 2-(3,4-difluorophenyl)-1,2,4-oxadiazolidin-3,5-dione as the residue.

Workup

  1. additionis charged into a glass reaction vessel
  2. customequipped with a mechanical stirrer
  3. additionis slowly added
  4. additionAfter the addition
  5. stirringis completed stirring
  6. filtrationThe resulting aqueous solution is then filtered
  7. temperaturethe filtrate is cooled
  8. customto form a precipitate
  9. filtrationThe precipitate is recovered by filtration
  10. customis dried
  11. dissolutionThe dried product is then dissolved in a methylene chloride-tetrahydrofuran mixture
  12. dry with materialthe resulting solution is dried over anhydrous magnesium sulfate
  13. filtrationfiltered

Sources & evidence

ORD record
ord-3f1192254f0242b59edd81775cce6600
Source dataset
uspto-grants-1976_05
Patent number
US03959478

Reaction notes

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