6-Chloro-5-fluoro-2-oxindole

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To the mixture of 6-chloro-5-fluoroindolin-2-one (Natrochem) (2.88 g, 15.5 mmol) and 3-chloro-2-fluorobenzaldehyde (3.69 g, 23.3 mmol) (Aldrich) in methanol (140 mL) was added piperidine (3.96 g, 46.6 mmol) (Aldrich) dropwise. The mixture was then heated at 50° C. for 3 h. After cooled to 4° C., the mixture was filtered and resulting precipitate was collected, dried to give E/Z-6-chloro-3-(3-chloro-2-fluoro-benzylidene)-5-fluoro-1,3-dihydro-indol-2-one as a yellow solid (Yield 4.4 g, 87%). After cooled to 4° C. the mixture was filtered resulting precipitate was collected dried

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Compound (III) is obtained by cyclizing (II) with an acid as shown in step [b] of Scheme 1. Compound (II) is dissolved in a mixture of an acid and a cosolvent, preferably the acid is glacial acetic acid in which instance the preferred cosolvent is water or the acid is hydrochloric acid in which instance the preferred cosolvent is methylene chloride. With acetic acid the ratio of the acid and cosolvent mixture ranges from 2:1 to pure acetic acid respectively, the preferred ratio being 6:1. With HCl, much less acid is required, preferably 1:4 3N HCl to CH2Cl2. Once compound (II) is dissolved, the reaction mixture is stirred at ambient temperature for from 6 to 7 hours to produce 5-fluoro-6-chlorooxindole (III). Compound (III) is readily purified by recrystallization from ethyl acetate to yield an off-white solid.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Compound (III) is obtained by cyclizing (II) with an acid as shown in step [b] of Scheme 1. Compound (II) is dissolved in a mixture of an acid and a cosolvent, preferably the acid is glacial acetic acid in which instance the preferred cosolvent is water or the acid is hydrochloric acid in which instance the preferred cosolvent is methylene chloride. With acetic acid the ratio of the acid and cosolvent mixture ranges from 2:1 to pure acetic acid respectively, the preferred ratio being 6:1. With HCl, much less acid is required, preferably 1:4 3N HCl to CH2Cl2. Once compound (II) is dissolved, the reaction mixture is stirred at ambient temperature for from 6 to 7 hours to produce 5-fluoro-6-chlorooxindole (III). Compound (III) is readily purified by recrystallization from ethyl acetate to yield an off-white solid.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Compound (III) is obtained by cyclizing (II) with an acid as shown in step [b] of Scheme 1. Compound (II) is dissolved in a mixture of an acid and a cosolvent, preferably the acid is glacial acetic acid in which instance the preferred cosolvent is water or the acid is hydrochloric acid in which instance the preferred cosolvent is methylene chloride. With acetic acid the ratio of the acid and cosolvent mixture ranges from 2:1 to pure acetic acid respectively, the preferred ratio being 6:1. With HCl, much less acid is required, preferably 1:4 3N HCl to CH2Cl2. Once compound (II) is dissolved, the reaction mixture is stirred at ambient temperature for from 6 to 7 hours to produce 5-fluoro-6-chlorooxindole (III). Compound (III) is readily purified by recrystallization from ethyl acetate to yield an off-white solid.

Conditions: temp:70.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To the mixture of 6-chloro-5-fluoro-1,3-dihydro-indol-2-one (500 mg, 2.7 mmol) and 2-(4-chloro-2-formyl-phenoxy)-2-ethyl-butyric acid methyl ester (844 mg, 2.97 mmol) in methanol (5 mL) was added pyrrolidine (95 mg, 1.35 mmol) dropwise. The mixture was then heated at 70° C. for 1 h. After cooled to room temperature, the mixture was partitioned between EtOAc and diluted HCl solution. The organic phase was washed with water, brine, dried over anhydrous Na2SO4 and concentrated to give the crude product as a red-yellow solid, which was used for the next step reaction without further purification. After cooled to room temperature the mixture was partitioned between EtOAc and diluted HCl solution The organic phase was washed with water, brine dried over anhydrous Na2SO4 concentrated

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a slurry of 6-chloro-5-fluoro-2-oxindole (0.04 mole) in acetonitrile (80 ml) was added chlorosulfonyl isocyanate (6.65 g, 0.047 mole) and the mixture was stirred for 45 minutes. Water (100 ml) was then added and the aqueous mixture was stirred for one hour. The precipitate which formed was filtered off and recrystallized from acetonitrile to give 0.92 g of the title product. Extraction of the filtrate from the aqueous reaction mixture with ethyl acetate (300 ml) followed by drying the extract over MgSO4 and then evaporating it under reduced pressure gave additional product. Recrystallization from acetonitrile gave an additional 2.2 g of product, m.p. 229°-231° C. the aqueous mixture was stirred for one hour The precipitate which formed was filtered off recrystallized from acetonitrile

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To the mixture of 6-chloro-5-fluoroindolin-2-one (Natrochem) (2.88 g, 15.5 mmol) and 3-chloro-2-fluorobenzaldehyde (3.69 g, 23.3 mmol) (Aldrich) in methanol (140 mL) was added piperidine (3.96 g, 46.6 mmol) (Aldrich) dropwise. The mixture was then heated at 50° C. for 3 h. After cooled to 4° C., the mixture was filtered and resulting precipitate was collected, dried to give E/Z-6-chloro-3-(3-chloro-2-fluoro-benzylidene)-5-fluoro-1,3-dihydro-indol-2-one as a yellow solid (Yield 4.4 g, 87%). After cooled to 4° C. the mixture was filtered resulting precipitate was collected dried

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Compound (III) is obtained by cyclizing (II) with an acid as shown in step [b] of Scheme 1. Compound (II) is dissolved in a mixture of an acid and a cosolvent, preferably the acid is glacial acetic acid in which instance the preferred cosolvent is water or the acid is hydrochloric acid in which instance the preferred cosolvent is methylene chloride. With acetic acid the ratio of the acid and cosolvent mixture ranges from 2:1 to pure acetic acid respectively, the preferred ratio being 6:1. With HCl, much less acid is required, preferably 1:4 3N HCl to CH2Cl2. Once compound (II) is dissolved, the reaction mixture is stirred at ambient temperature for from 6 to 7 hours to produce 5-fluoro-6-chlorooxindole (III). Compound (III) is readily purified by recrystallization from ethyl acetate to yield an off-white solid.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Compound (III) is obtained by cyclizing (II) with an acid as shown in step [b] of Scheme 1. Compound (II) is dissolved in a mixture of an acid and a cosolvent, preferably the acid is glacial acetic acid in which instance the preferred cosolvent is water or the acid is hydrochloric acid in which instance the preferred cosolvent is methylene chloride. With acetic acid the ratio of the acid and cosolvent mixture ranges from 2:1 to pure acetic acid respectively, the preferred ratio being 6:1. With HCl, much less acid is required, preferably 1:4 3N HCl to CH2Cl2. Once compound (II) is dissolved, the reaction mixture is stirred at ambient temperature for from 6 to 7 hours to produce 5-fluoro-6-chlorooxindole (III). Compound (III) is readily purified by recrystallization from ethyl acetate to yield an off-white solid.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 26.63 g. sample of the N-(2-chloro)-2-chloro-4-fluoroaniline was thoroughly mixed with 64 g. of anhydrous aluminum chloride, and the mixture was heated at 210°-230° C. for 8.5 hours. The reaction mixture was then poured onto a mixture of ice an 1N hydrochloric acid, with stirring. Stirring was continued for 30 minutes, and then the solid was collected by filtration (22.0 g.). The solid was dissolved in 1:1 ethyl acetate-hexane and chromatographed on 800 g. of silica gel. Elution of the column, followed by evaporation of the fractions, produced 11.7 g. of the N-(2-chloroacetyl)-3-chloro-4-fluoroaniline, followed by 3.0 g. of 6-chloro-5-fluorine-2-oxindole. The latter material was recrystallized from toluene to give 1.70 g. (7% yield) of the title compound, m.p. 196°-206° C. Analysis by NMR spectroscopy indicated that the product was contaminated by some 4-chloro-5-fluorooxindole. A second crop weighing 0.8 g. was obtained. Stirring the solid was collected by filtration (22.0 g.) The solid was dissolved in 1:1 ethyl acetate-hexane chromatographed on 800 g Elution of the column followed by evaporation of the fractions produced 11.7 g The latter material was recrystallized from toluene to give 1.70 g

Conditions: temp:0.00; pressure:0.00; stir: