Ethyl chloroformate → Ethyl (4-chloro-2-fluorophenyl)carbamate

HRID 1290628Notes

Reaction equation

HRID 1290628 reaction equation
[Cl:1][C:2]1[CH:8]=[CH:7][C:5]([NH2:6])=[C:4]([F:9])[CH:3]=1.Cl[C:11]([O:13][CH2:14][CH3:15])=[O:12]>N1C=CC=CC=1>[Cl:1][C:2]1[CH:8]=[CH:7][C:5]([NH:6][C:11](=[O:12])[O:13][CH2:14][CH3:15])=[C:4]([F:9])[CH:3]=1

Participants

4

Reactant 2

HCID 10928Ethyl chloroformateHCID 938984-Chloro-2-fluoroaniline

Product 1

HCID 887936Ethyl (4-chloro-2-fluorophenyl)carbamateYield 93.9%

Reagents, catalysts & solvents 1

HCID 1049PyridineSolvent

Procedure

A solution of 6.9 grams (47 mmole) of 4-chloro-2-fluoroaniline in 75 mL of pyridine was stirred and cooled in an ice bath. During 15 minutes, 5.4 grams (50 mmole) of ethyl chloroformate was added dropwise. Upon completion of the addition the reaction mixture was heated at 60°-70° C. for 1.5 hours, then concentrated under reduced pressure to a residue. The residue was stirred with 150 mL of aqueous 3N hydrochloric acid, and the resulting precipitate was collected by filtration. The precipitate was washed with aqueous 3N hydrochloric acid and then with water. The precipitate was dried under ambient conditions for about 18 hours, then dried under vacuum for two hours, yielding 9.6 grams of ethyl N-(4-chloro-2-fluoro-phenyl)carbamate. The NMR spectrum was consistent with the proposed structure.

Workup

  1. temperaturecooled in an ice bath
  2. additionUpon completion of the addition the reaction mixture
  3. temperaturewas heated at 60°-70° C. for 1.5 hours
  4. concentrationconcentrated under reduced pressure to a residue
  5. filtrationthe resulting precipitate was collected by filtration
  6. washThe precipitate was washed with aqueous 3N hydrochloric acid
  7. customThe precipitate was dried under ambient conditions for about 18 hours
  8. customdried under vacuum for two hours

Sources & evidence

ORD record
ord-f8ac787b1c5342abbdf466482f6f4315
Source dataset
uspto-grants-1998_05
Patent number
US05753595

Reaction notes

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