Water → 5-Aminoindole-1-carboxylic acid phenylamide

Temperature

80 °C

5-Nitroindole-1-carboxylic acid phenylamide (3.53 g, 12.3 mmol) was dissolved in ethanol (250 ml); water (50 ml), electrolytic iron powder (2.75 g, 49.2 mmol), ammonium chloride (5.26 g, 98.4 mmol) were added thereto; and the reaction mixture was heated and stirred at 80° C. for 2 hours. After cooling to room temperature, the reaction mixture was filtered off; insoluble portions were washed with ethyl acetate; and the filtrate was concentrated under reduced pressure. The residue was partitioned between water and a solvent mixture of ethyl acetate and tetrahydrofuran; and the organic layer was washed with brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was solidified by diethyl ether; the crystals were suspended in diethyl ether, filtered off, washed with diethyl ether, and dried to yield the title compound as pale red powder (681 mg, 2.71 mmol, 22.0%). The mother liquor was concentrated under reduced pressure, which was then treated by the similar methods to yield the title compound (590 mg, 2.35 mmol, 19.1%) as pale red powder (secondary crystals).

1. temperatureand the reaction mixture was heated
2. temperatureAfter cooling to room temperature
3. filtrationthe reaction mixture was filtered off
4. washinsoluble portions were washed with ethyl acetate
5. concentrationand the filtrate was concentrated under reduced pressure
6. customThe residue was partitioned between water
7. additiona solvent mixture of ethyl acetate and tetrahydrofuran
8. washand the organic layer was washed with brine
9. dry with materialdried over anhydrous sodium sulfate
10. concentrationconcentrated under reduced pressure
11. filtrationfiltered off
12. washwashed with diethyl ether
13. customdried

ORD record

ord-9c382c34dc874cad9e0e647f891fb56f

Source dataset

uspto-grants-2008_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07468380B2