Synthesis
General procedure for the synthesis of N-Boc-5-aminoindole from tert-butyl 5-nitro-1H-indole-1-carboxylate: tert-butyl 5-nitro-1H-indole-1-carboxylate (525 mg, 2.0 mmol) was dissolved in ethyl acetate (8 mL), and 10% palladium-carbon-catalyst (50 mg) was added. The reaction mixture was stirred overnight at room temperature in a hydrogen atmosphere. Upon completion of the reaction, the catalyst was removed by suction filtration and the filtrate was concentrated under reduced pressure to afford the white solid product N-Boc-5-aminoindole (469 mg, 100% yield).
References
[1] Patent: CN104311541, 2017, B. Location in patent: Paragraph 0164; 0165
[2] Patent: US2009/247568, 2009, A1. Location in patent: Page/Page column 36
[3] Journal of Medicinal Chemistry, 2013, vol. 56, # 15, p. 6273 - 6277
[4] Synthetic Communications, 2006, vol. 36, # 14, p. 2069 - 2077
[5] Journal of Medicinal Chemistry, 2011, vol. 54, # 4, p. 1106 - 1110
