Hydrochloric Acid → 1-Chloro-5-fluoro-4-isocyanato-2-nitrobenzene

HRID 233432Notes

Reaction equation

Cl.[Cl:2][C:3]1[C:9]([N+:10]([O-:12])=[O:11])=[CH:8][C:6]([NH2:7])=[C:5]([F:13])[CH:4]=1.[C:14](Cl)(Cl)=[O:15]>C1(C)C=CC=CC=1>[Cl:2][C:3]1[C:9]([N+:10]([O-:12])=[O:11])=[CH:8][C:6]([N:7]=[C:14]=[O:15])=[C:5]([F:13])[CH:4]=1

Participants

Conditions

Temperature: 85 °C

Procedure

Dry HCl gas is passed into a solution of 66.7 g (0.35 mol) of 4-chloro-2-fluoro-5-nitroaniline in 1180 ml of toluene at 0° to 5° C. until the solution is saturated. 34.7 g (0.35 ml) of phosgene are subsequently metered in, and the mixture is heated slowly at 85° C. After a further 17.3 g (0.175 mol) of phosgene have been added and the mixture has been heated at 85° C. (1 h), the batch is flushed with nitrogen until free from phosgene and cooled. Removal of the precipitate by filtration and concentration gives 28.6 g (37.7% of theory) of 4-chloro-2-fluoro-5-nitrophenyl isocyanate of melting point 43°-46° C.; boiling point 125° C. at 0.3 torr (bulb-tube distillation).

Workup

temperaturethe mixture has been heated at 85° C. (1 h)
customthe batch is flushed with nitrogen until free from phosgene
temperaturecooled
customRemoval of the precipitate
filtrationby filtration and concentration

Sources & evidence

ORD record: ord-c7813ae7825643d89c4024157d93ba11
Source dataset: uspto-grants-1997_01
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US05593944

Reaction notes

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