Hydrochloric Acid → 2,4-Difluoro-3,5-dichlorophenyl isocyanate

HRID 1731552Notes

Reaction equation

HRID 1731552 reaction equation
Cl.[F:2][C:3]1[C:9]([Cl:10])=[C:8]([F:11])[C:7]([Cl:12])=[CH:6][C:4]=1[NH2:5].[C:13](Cl)(Cl)=[O:14]>C1(C)C=CC=CC=1>[F:2][C:3]1[C:9]([Cl:10])=[C:8]([F:11])[C:7]([Cl:12])=[CH:6][C:4]=1[N:5]=[C:13]=[O:14]

Participants

5

Reactant 3

HCID 313Hydrochloric Acid2×HCID 6371Phosgene2×HCID 27740003,5-Dichloro-2,4-difluorobenzenamine

Product 1

HCID 140475992,4-Difluoro-3,5-dichlorophenyl isocyanate

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

Hydrogen chloride was passed into a well-stirred solution of 39.6 gm (0.20 mol) of 2,4-difluoro-3,5-dichloroaniline in 400 ml of toluene until a precipitate no longer separated out. The heterogeneous mixture thus obtained was cooled to 5° to 10° C. At this temperature, 40 gm (0.4 mol) of phosgene were passed in, with stirring. The mixture was then heated slowly, with stirring, so that after about two hours a temperature of 100° to 105° C. was reached. Stirring was then continued for seven hours at this temperature. During this time, a clear solution was formed, and hydrogen chloride was liberated. Nitrogen was then passed into the mixture for one hour at the same temperature to drive off the excess phosgene. Thereafter the solvent was distilled off, in vacuo at the end. The crude product which remained was distilled in a water pump vacuum.

Workup

  1. customno longer separated out
  2. customThe heterogeneous mixture thus obtained
  3. temperaturewas cooled to 5° to 10° C
  4. temperatureThe mixture was then heated slowly
  5. stirringwith stirring
  6. stirringStirring
  7. waitwas then continued for seven hours at this temperature
  8. customDuring this time, a clear solution was formed
  9. waitNitrogen was then passed into the mixture for one hour at the same temperature
  10. distillationThereafter the solvent was distilled off, in vacuo at the end
  11. distillationThe crude product which remained was distilled in a water pump vacuum

Sources & evidence

ORD record
ord-e34b37b7ac934d19947098e2862d2920
Source dataset
uspto-grants-1986_11
Patent number
US04622340

Reaction notes

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