Hydrochloric Acid → 6-Fluoro-5-methyl-2-oxindole
Reaktionsgleichung
Cl[CH2:2][C:3]([NH:5][C:6]1[CH:11]=[CH:10][C:9]([CH3:12])=[C:8]([F:13])[CH:7]=1)=[O:4].[Cl-].[Al+3].[Cl-].[Cl-].Cl>>[F:13][C:8]1[CH:7]=[C:6]2[C:11]([CH2:2][C:3](=[O:4])[NH:5]2)=[CH:10][C:9]=1[CH3:12]Komponenten
4
Versuchsvorschrift
An intimate mixture of 11.62 g (57.6 mmol) of N-(2-chloroacetyl)-3-fluoro-4-methylaniline and 30.6 g (229.5 mmol) of anhydrous aluminum chloride was heated to 210°-220° C. After 4 hours, the reaction mixture was cooled and then added to 100 ml of 1N hydrochloric acid and 50 ml of ice. A tan solid formed, which was collected by filtration and recrystallized from aqueous ethanol. Three crops were obtained, weighing 4.49 g, 2.28 g and 1.0 g, respectively. The first two crops comprised a mixture of isomers (4-fluoro-5-methyl and 6-fluoro-5-methyl-2-oxindoles). The crop weighing 1.0 g was further recrystallized from water to give 280 mg of the title compound, mp 168.5°-171° C.