4-Amino-2,5-difluorophenol

Uses

4-Amino-2,5-difluorophenolis used in preparation of Phenoxypyridylpyrimidine derivatives for use as Inositol requiring enzyme 1 activity modulators.

Synthesis

1-(Benzyloxy)-2,5-difluoro-4-nitrobenzene (9.21 g) was dissolved in methanol (300 ml) and 10% palladium-carbon catalyst (921 mg) was added. The reaction was stirred at room temperature for 24 hours and 20 minutes under hydrogen atmosphere. Upon completion of the reaction, the atmosphere in the reaction vessel was replaced with nitrogen to terminate the reaction and the catalyst was removed by filtration through diatomaceous earth. The filtrate was concentrated under reduced pressure to afford the title compound 4-amino-2,5-difluorophenol as a brown solid (4.96 g, 99% yield). The product was characterized by 1H-NMR (DMSO-d6): δ 4.67 (1H, s), 6.53-6.64 (1H, m), 9.03 (1H, s).

References

[1] Patent: US2008/214815, 2008, A1. Location in patent: Page/Page column 18
[2] Patent: EP2119706, 2009, A1. Location in patent: Page/Page column 45
[3] Patent: EP1889836, 2008, A1. Location in patent: Page/Page column 82
[4] Patent: WO2013/180949, 2013, A1. Location in patent: Paragraph 0183
[5] Patent: WO2014/22116, 2014, A2. Location in patent: Paragraph 0181