ethyl 5-chloro-1H-indole-2-carboxylate

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

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

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

Conditions: temp:60.01; pressure:0.00; stir:

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

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

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

Procedure: To a partial suspension of ethyl 5-chloroindole-2-carboxylate (698 mg, 3.1 mmol) and N-(phenylthio)succinimide (683 mg, 3.3 mmol) in anhydrous methylene chloride (20 mL) at ambient temperature under an inert gas atmosphere was added boron trifluoride etherate (0.12 mL, 1.0 mmol). The reaction was monitored by tlc (thin layer chromatography) until complete. After 2 hours, the reaction was diluted with chloroform and neutralized with aq. NaHCO3. The organic layer was dried (Na2SO4), filtered through a pad of charcoal, and the solvents evaporated. The residue was triturated with hexanes as the product crystallized out to yield the title product, mp 160°-162° C. [see Table II, mp 163°-164° C⟧ This material was used as is. The organic layer was dried (Na2SO4) filtered through a pad of charcoal the solvents evaporated The residue was triturated with hexanes as the product crystallized out

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

Procedure: To a partial suspension of ethyl 5-chloroindole-2-carboxylate (698 mg, 3.1 mmol) and N-(phenylthio)succinimide (683 mg, 3.3 mmol) in anhydrous methylene chloride (20 mL) at ambient temperature under an inert gas atmosphere was added boron trifluoride etherate (0.12 mL, 1.0 mmol). The reaction was monitored by tlc (thin layer chromatography) until complete. After 2 hours, the reaction was diluted with chloroform and neutralized with aq. NaHCO3. The organic layer was dried (Na2SO4), filtered through a pad of charcoal, and the solvents evaporated. The residue was triturated with hexanes as the product crystallized out to yield the title product, mp 160°-162° C. [see Table II, mp 163°-164° C⟧ This material was used as is. The organic layer was dried (Na2SO4) filtered through a pad of charcoal the solvents evaporated The residue was triturated with hexanes as the product crystallized out

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

Procedure: To a cold (0°), stirred solution of ethyl 5-chloroindole-2-carboxylate (223 mg) in 4.5 mL dry tetrahydrofuran, under argon, was added 0.55 mL of a solution of ethylmagnesium bromide in ether. The resultant mixture was stirred for 30 min then cooled to -78°. Solid S-phenyl benzenethiosulfonate (300 mg) was added and the mixture stirred at 78° for 30 min and 0° for 1 h. The mixture was then diluted with ether and saturated aqueous ammonium chloride added. The organic layer was separated, washed with water and brine and dried over MgSO4. Filtration and concentration gave a yellow oil which was purified by flash chromatography on silica gel. Elution with hexane-ethyl acetate (85:15) gave the title product. then cooled to -78° added The organic layer was separated washed with water and brine dried over MgSO4 Filtration and concentration gave a yellow oil which was purified by flash chromatography on silica gel Elution with hexane-ethyl acetate (85:15)

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

Procedure: After phosphorus oxychloride (2.0 ml) was added to N-methylformanilide (2.9 g), and the mixture was stirred for 15 minutes, 1,2-dichloroethane (50 ml) and ethyl 5-chloroindole-2-carboxylate (4.0 g) were added, and the resultant mixture was heated under reflux for 1 hour. The reaction mixture was poured into an aqueous solution (28 ml) of sodium acetate (14 g) under ice cooling. After stirring for 18 hours, insoluble matter was collected by filtration. This product was successively washed with water and diethyl ether to obtain the title compound (3.56 g). under reflux for 1 hour After stirring for 18 hours insoluble matter was collected by filtration This product was successively washed with water and diethyl ether

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

Procedure: N-Bromosuccinimide (440 mg) was added to a solution of ethyl 5-chloroindole-2-carboxylate (500 mg) in N,N-dimethylformamide (10 ml). The reaction mixture was stirred at room temperature for 18 hours, and the solvent was distilled off under reduced pressure. The residue was partitioned in ethyl acetate and water, and a water layer was extracted with ethyl acetate. The resultant organic layers were combined, washed with saturated aqueous solution of sodium chloride and then dried over anhydrous sodium sulfate. The solvent was distilled off, the residue was purified by column chromatography on silica gel (ethyl acetate:hexane=1:9), and white powder thus obtained was washed with hexane to obtain the title compound (680 mg). the solvent was distilled off under reduced pressure The residue was partitioned in ethyl acetate water, and a water layer was extracted with ethyl acetate washed with saturated aqueous solution of sodium chloride dried over anhydrous sodium sulfate The solvent was distilled off the residue was purified by column chromatography on silica gel (ethyl acetate:hexane=1:9), and white powder thus obtained was washed with hexane

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

Procedure: Ethyl 5-chloroindole-2-carboxylate (1.4 g) was dissolved in N,N-dimethylformamide (30 ml), and potassium carbonate (2.9 g) and benzyl chloride (2.4 ml) were added. The mixture was heated and stirred for 1.5 hours on a hot bath controlled to 100° C. The reaction mixture was concentrated under reduced pressure, and the residue was poured into ice water and extracted with ethyl acetate. The resultant organic layer was washed with saturated aqueous solution of sodium chloride and dried over anhydrous sodium sulfate. The solvent was distilled off, and the residue was purified by column chromatagraphy on silica gel (ethyl acetate:hexane=1:19) and crystallized from diethyl ether-hexane to obtain the title compound (1.6 g). The mixture was heated controlled to 100° C The reaction mixture was concentrated under reduced pressure the residue was poured into ice water extracted with ethyl acetate The resultant organic layer was washed with saturated aqueous solution of sodium chloride dried over anhydrous sodium sulfate The solvent was distilled off the residue was purified by column chromatagraphy on silica gel (ethyl acetate:hexane=1:19) crystallized from diethyl ether-hexane