反应详情

A suspension of [2-(4,5-difluoro-2-nitro-phenyl)-vinyl]-dimethyl-amine (7.0 g, 30.7 mmol) and 10% palladium on charcoal (1.4 g) in methyl alcohol was hydrogenated in a Parr apparatus at 50 psi for 2 h and then filtered through Celite. The filtrate was concentrated in vacuo and the crude product purified by silica gel column chromatography (hexanes/ethyl acetate, 8:2) to afford 5,6-difluoroindole (1.28 g, 28%) as a yellow solid. 1H-NMR δ(400 MHz, CDCl3) 8.10 (1H, br s), 7.36 (1H, dd, J=10.7, 7.8 Hz), 7.22 (1H, t, J=2.8 Hz), 7.17 (1H, dd, J=7.4, 3.1 Hz), 6.50 (1H, m).

1. filtrationfiltered through Celite
2. concentrationThe filtrate was concentrated in vacuo
3. customthe crude product purified by silica gel column chromatography (hexanes/ethyl acetate, 8:2)