2-ethyl-1H-indole

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: In an ice water bath, trifluoroacetic acid (4.4 g, 38.6 mmol), triethylsilane (9.02 g, 77.6 mmol), dichloromethane 15 mL were added into a reaction vessel. After stirring for 5 min, a dichloromethane solution dissolving 2-ethyl-1H-indole (3.74 g, 25.8 mmol) and p-nitro benzaldehyde (4.29 g, 28.4 mmol) was added dropwise slowly into the reaction vessel. After completion of dropwise addition it was reacted maintaining this temperature for 1 h, adjusted to pH=8-9 with 2 M solution of sodium hydroxide. An aqueous solution of sodium chloride was added, and extracted with dichloromethane. The extract was dried over anhydrous sodium sulfate, concentrated to dryness to obtain a red brown solid, washed with a small amount of diethyl ether to obtain a yellow powdered solid 3 g, at a yield of 41.5%. was added dropwise slowly into the reaction vessel After completion of dropwise addition it was reacted maintaining this temperature for 1 h extracted with dichloromethane The extract was dried over anhydrous sodium sulfate concentrated to dryness to obtain a red brown solid washed with a small amount of diethyl ether

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

Procedure: In an ice water bath, 2-methylindole (5 g, 38.1 mmol), 300 mL anhydrous diethyl ether, 2.4 M n-BuLi 47.5 mL (114 mmol), tert-butanol (8.5 g, 75.8 mmol) were added into a reaction vessel. Upon completion of addition, under protection of nitrogen, the reaction was stirred at room temperature for 0.5 h. Then the system was cooled to −70° C., and iodomethane (10.245 g, 72.2 mmol) was added dropwise. Upon completion of addition, it was reacted for 2 h maintaining this temperature. Then it was warmed up to −40° C. 2 mL water was added, and then warmed up to room temperature. The system was poured into water, adjusted to pH=6, extracted with diethyl ether, dried and rotate evaporated to dryness to obtain the product 3.74 g, at a yield of 67.7%. Upon completion of addition Then the system was cooled to −70° C. Upon completion of addition, it was reacted for 2 h maintaining this temperature Then it was warmed up to −40° C warmed up to room temperature extracted with diethyl ether dried rotate evaporated to dryness

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

Procedure: In an ice water bath, 2-methylindole (5 g, 38.1 mmol), 300 mL anhydrous diethyl ether, 2.4 M n-BuLi 47.5 mL (114 mmol), tert-butanol (8.5 g, 75.8 mmol) were added into a reaction vessel. Upon completion of addition, under protection of nitrogen, the reaction was stirred at room temperature for 0.5 h. Then the system was cooled to −70° C., and iodomethane (10.245 g, 72.2 mmol) was added dropwise. Upon completion of addition, it was reacted for 2 h maintaining this temperature. Then it was warmed up to −40° C. 2 mL water was added, and then warmed up to room temperature. The system was poured into water, adjusted to pH=6, extracted with diethyl ether, dried and rotate evaporated to dryness to obtain the product 3.74 g, at a yield of 67.7%. Upon completion of addition Then the system was cooled to −70° C. Upon completion of addition, it was reacted for 2 h maintaining this temperature Then it was warmed up to −40° C warmed up to room temperature extracted with diethyl ether dried rotate evaporated to dryness

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

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

Procedure: 1.2 g (4.2 mmol) 1-benzenesulphonyl-2-ethyl-1H-indole in 10 mL EtOH were combined with 5 mL of a (20 mmol) 4 N aqueous sodium hydroxide solution and refluxed for 8 h. Then the solvent was eliminated using the rotary evaporator and the residue was diluted with ice water. After acidifying with semi-concentrated aqueous hydrochloric acid the grease precipitated was extracted with ethyl acetate. The organic phase was dried on sodium sulphate, filtered off, evaporated down and dried. refluxed for 8 h the rotary evaporator the residue was diluted with ice water precipitated was extracted with ethyl acetate The organic phase was dried on sodium sulphate filtered off evaporated down dried

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

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

Procedure: This synthesis could be achieved beginning with a standard nitration of 2-ethylindole using sodium nitrate and sulfuric acid similar to that cited in Yokoyama; Tanaka; Yamane; Kurita; Chem. Lett.; 7; 1991; 1125-1128. The resultant 5-nitro-2-ethylindole could be reduced to the desired amino compound using catalytic hydrogenation as in 28b). This synthesis

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

Procedure: Indole-7 carboxyldehyde (I-1). Ethyl Indole-7 m carboxylate was prepared according to literature procedure {Batcho B. and Leimgruber, K., Org. Syn. Vol IIV, page 34-40). To a solution of methyl 7-indolecarboxylate (13 g, 74.2 mmol) in 250 ml of anhydrous THF was added LiAlH4 (10.9 g, 0.288 mol) in portions, and reaction mixture was heated to reflux for 2 h. After cooling to room temperature, the excess hydride was quenched by addition of water (12 mL), 15% NaOH (12 mL) and water (26 mL). The solids were removed by filtration through a pad of Celite and filtrate was evaporated in vacuo to yield (1H-indol-7-yl)-methanol (10.7 g, 98%). 1HNMR (CDCl3). To a solution of the alcohol, (1H-indol-7-yl)-methanol (8.0 g, 54.3 mmol) in 400 mL of methylene chloride was added activated manganese (IV) oxide (85%, 41.0 g, 0.40 mol), and stirred at ambient temperature for 72 h. After additional of 200 mL of methylene chloride and 400 mL of methanol to the reaction mixture, the whole mixture was filtered through a pad of silica gel to remove solid materials. The filtrate was concentrated to afford a crude product, which was purified by a column chromatography on silica gel to yield 1H-indole-7-carbaldehyde, I-1 (6.55 g, 83%). 1HNMR (CDCl3). in portions, and reaction mixture was heated to reflux for 2 h the excess hydride was quenched by addition of water (12 mL), 15% NaOH (12 mL) and water (26 mL) The solids were removed by filtration through a pad of Celite and filtrate was evaporated in vacuo

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

Procedure: 0.66 g (4.2 mmol) 2-ethyl-1H-indole in 10 mL acetic acid were mixed with 1.3 g (20 mmol) sodium cyanoborohydride and stirred for one day at RT. The reaction mixture was evaporated down using the rotary evaporator, combined with 20 mL aqueous 4N hydrochloric acid and stirred for 1 h at RT. While cooling with ice 45 mL of an aqueous 4N sodium hydroxide solution were then added and the mixture was extracted with ethyl acetate. The organic phase was dried on sodium sulphate, filtered, evaporated down and the residue was dried in vacuo. The reaction mixture was evaporated down the rotary evaporator stirred for 1 h at RT While cooling with ice 45 mL of an aqueous 4N sodium hydroxide solution were then added the mixture was extracted with ethyl acetate The organic phase was dried on sodium sulphate filtered evaporated down the residue was dried in vacuo

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

Procedure: 0.66 g (4.2 mmol) 2-ethyl-1H-indole in 10 mL acetic acid were mixed with 1.3 g (20 mmol) sodium cyanoborohydride and the mixture was stirred for one day at RT. The reaction mixture was evaporated down using the rotary evaporator, combined with 20 mL of 4N aqueous hydrochloric acid and stirred for 1 h at RT. While cooling with ice, 45 mL of a 4N aqueous sodium hydroxide solution were then added and the mixture was extracted with ethyl acetate. The organic phase was dried on sodium sulphate, filtered, evaporated down and the residue was dried in vacuo. The reaction mixture was evaporated down the rotary evaporator stirred for 1 h at RT While cooling with ice, 45 mL of a 4N aqueous sodium hydroxide solution were then added the mixture was extracted with ethyl acetate The organic phase was dried on sodium sulphate filtered evaporated down the residue was dried in vacuo