Sulfuric Acid → 2,6-Difluorobenzamide
Reaction equation
Cl[C:2]1[C:3]([F:11])=[C:4]([C:7]([F:10])=[CH:8][CH:9]=1)[C:5]#[N:6].[H][H].C(N(CC)CC)C.S(=O)(=O)(O)[OH:22]>CO.[C].[Pd]>[F:10][C:7]1[CH:8]=[CH:9][CH:2]=[C:3]([F:11])[C:4]=1[C:5]([NH2:6])=[O:22]Participants
Procedure
For example, when 3-chloro-2,6-difluorobenzonitrile is dissolved in methanol and reacted with hydrogen gas in the presence of palladium-carbon catalyst and triethylamine under the hydrogen pressure of 5 kg/cm2, the DFBN is obtainable. The DFBN is then heated and dissolved at 70° C. and dropwise added to 90% sulfuric acid, and the reaction is performed at 70° to 80° C. to obtain a 2,6-difluorobenzamide. The product is then dissolved in 1,2-dichloroethane and an oxyalyl chloride is dropwise added to the solution at 20° to 40° C., and the reaction is performed under reflux to obtain 2,6-difluorobenzoyl isocyanate. A dioxane solution of 3,5-dichloro-4-(3-chloro-5-trifluoromethyl-2-pyridyloxy) aniline is dropwise added to a dioxane solution of the isocyanate at 40° to 50° C. and the reaction was performed to obtain N-(2,6-difluorobenzoyl)-N'-[3,5-dichloro-4-(3-chloro-5-trifluoromethyl-2-pyridyloxy)phenyl]urea having a melting point of 203° to 205° C. This derivative is effective to combat a various kinds of undesirable insects, as disclosed in the Japanese Unexamined Patent Publication 125677/1979, U.S. Pat. Nos. 4,173,637, 4,173,638 and 4,310,530.
Workup
- temperatureThe DFBN is then heated
- dissolutiondissolved at 70° C.
- customis performed at 70° to 80° C.
Sources & evidence
- ORD record
- ord-fc51f19aca47421c909b7b01c2153de9
- Source dataset
- uspto-grants-1983_09
- Patent number
- US04406841
Reaction notes
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