C(Cl)(=O)[C:2](Cl)=[O:3].[F:7][C:8]1[CH:16]=[CH:15][CH:14]=[C:13]([F:17])[C:9]=1[C:10]([NH2:12])=[O:11]>ClCCCl>[F:7][C:8]1[CH:16]=[CH:15][CH:14]=[C:13]([F:17])[C:9]=1[C:10]([N:12]=[C:2]=[O:3])=[O:11]Oxalyl chloride (5.5 g) was added slowly to a suspension of 2,6-difluorobenzamide (6.0 g) in 1,2-dichloroethane maintained at a temperature within the range -10° to -5° C. When the addition was complete the mixture was allowed to warm to the ambient temperature, and then gradually heated to the reflux temperature and maintained thereat for a period of 16 hours. The solvent was then removed by evaporation under reduced pressure and the residual oil purified by distillation to yield 2,6-difluorobenzoyl isocyanate, b.p. 60°-61°/0.7 mm.
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