Synthesis
GENERAL STEPS: A suspension of 2-hydroxymethyl-6-chloroindole (1 mmol) with activated MnO2 (10 mmol) in DMF (30 mL) was stirred at room temperature for 12 hours. After completion of the reaction, the mixture was filtered through a diatomaceous earth pad. The filtrate was concentrated under vacuum and the residue was purified by column chromatography to afford 6-chloro-1H-indole-2-carbaldehyde using EtOAc-hexane mixed solvent as eluent.
References
[1] European Journal of Medicinal Chemistry, 2016, vol. 121, p. 561 - 577
[2] Patent: US2003/144282, 2003, A1
[3] Journal of Medicinal Chemistry, 2007, vol. 50, # 6, p. 1380 - 1400
[4] Patent: US2008/9485, 2008, A1. Location in patent: Page/Page column 31
[5] Journal of Medicinal Chemistry, 2014, vol. 57, # 2, p. 364 - 377
