ethyl 1H-indole-4-carboxylate

Conditions: temp:190.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 3-bromo-5-{(S)-1-[(R)-1-(4-methoxy-phenyl)-ethyl]-pyrrolidin-2-yl}-pyridine (4.0 g, 11 mmol), 1H-indole-4-carboxylic acid ethyl ester (6.3 g, 33 mmol), K2CO3 (2.3 g, 16.6 mmol), copper iodide (0.42 g, 2.2 mmol) in NMP (22 mL) was heated in a microwave tube at 190° C. for 30 minutes. The resulting mixture was cooled to room temperature filtered through celite and concentrated under reduced pressure to give an oil. This oil was purified by silica gel column chromatography (30% ethyl acetate/heptane) to give the titled compound as a yellow solid (2.2 g, 42%). The resulting mixture was cooled to room temperature filtered through celite and concentrated under reduced pressure to give an oil This oil was purified by silica gel column chromatography (30% ethyl acetate/heptane)

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

Procedure: 5 g of 4-ethoxycarbonyl indole are added to a solution of 3.1 g of dimethylamino-2-nitroethylene in 20 ml of trifluoroethyl acetate refrigerated under argon. The reaction mixture is introduced into ice water after it had been standing overnight at room temperature. The aqueous phase is repeatedly extracted with ethyl acetate. The combined ethyl acetate extracts are extracted first with sodium bicarbonate solution, then a saturated sodium chloride solution, dried and evaporated. The residue is recrystallized from ethanol. Yield: 4.5 g of 4-ethoxycarbonyl-3-(2-nitrovinyl)-indole. Yellow crystals with a 197°-199° C. melting point. The aqueous phase is repeatedly extracted with ethyl acetate The combined ethyl acetate extracts are extracted first with sodium bicarbonate solution a saturated sodium chloride solution, dried evaporated The residue is recrystallized from ethanol with a 197°-199° C.

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

Procedure: A mixture of 13.24 g of ethyl indole-4-carboxylate, 15.98 g of acetonylacetone and 13.31 g of p-toluenesulfonic acid monohydrate in 50 ml of ethanol was refluxed for 10 hours. The ethanol was evaporated under reduced pressure, the residue was chromatographed on silica gel column with hexane - ethyl acetate (9 : 1) to give 7.45 g of ethyl 5,8-dimethylcarbazole-4-carboxylate. was refluxed for 10 hours The ethanol was evaporated under reduced pressure the residue was chromatographed on silica gel column with hexane - ethyl acetate (9 : 1)

Conditions: temp:190.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 3-bromo-5-{(S)-1-[(R)-1-(4-methoxy-phenyl)-ethyl]-pyrrolidin-2-yl}-pyridine (4.0 g, 11 mmol), 1H-indole-4-carboxylic acid ethyl ester (6.3 g, 33 mmol), K2CO3 (2.3 g, 16.6 mmol), copper iodide (0.42 g, 2.2 mmol) in NMP (22 mL) was heated in a microwave tube at 190° C. for 30 minutes. The resulting mixture was cooled to room temperature filtered through celite and concentrated under reduced pressure to give an oil. This oil was purified by silica gel column chromatography (30% ethyl acetate/heptane) to give the titled compound as a yellow solid (2.2 g, 42%). The resulting mixture was cooled to room temperature filtered through celite and concentrated under reduced pressure to give an oil This oil was purified by silica gel column chromatography (30% ethyl acetate/heptane)

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

Procedure: 5 g of 4-ethoxycarbonyl indole are added to a solution of 3.1 g of dimethylamino-2-nitroethylene in 20 ml of trifluoroethyl acetate refrigerated under argon. The reaction mixture is introduced into ice water after it had been standing overnight at room temperature. The aqueous phase is repeatedly extracted with ethyl acetate. The combined ethyl acetate extracts are extracted first with sodium bicarbonate solution, then a saturated sodium chloride solution, dried and evaporated. The residue is recrystallized from ethanol. Yield: 4.5 g of 4-ethoxycarbonyl-3-(2-nitrovinyl)-indole. Yellow crystals with a 197°-199° C. melting point. The aqueous phase is repeatedly extracted with ethyl acetate The combined ethyl acetate extracts are extracted first with sodium bicarbonate solution a saturated sodium chloride solution, dried evaporated The residue is recrystallized from ethanol with a 197°-199° C.