2-Bromo-4-fluoro-1-nitrobenzene → 7-bromo-5-fluoro-1H-indole

Temperature

-45 °C

2-bromo-4-fluoro-1-nitrobenzene (3.5 g, 15.9 mmol) was dissolved in anhydrous THF (160 ml) under N2. The reaction was cooled to −45° C. and vinyl magnesium bromide (3 eq, 1M) was added, the mixture was stirred for 30 min at this temperature. The reaction was quenched with NH4Cl (sat.) and 1N HCl. The aqueous layer was then extracted 3× with ether. The combined organic layers were washed with water and brine, dried over MgSO4, filtered and then concentrated under reduced pressure. The product was purified by flash chromatography on silica gel. 1H NMR (500 MHz, DMSO-d6): δ 11.45 (bs, 1H), 7.50 (t, 1H), 7.40 (dd, 1H), 7.25 (dd, 1H), 6.50 (dd, 1H).

1. customThe reaction was quenched with NH4Cl (sat.) and 1N HCl
2. extractionThe aqueous layer was then extracted 3× with ether
3. washThe combined organic layers were washed with water and brine
4. dry with materialdried over MgSO4
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure
7. customThe product was purified by flash chromatography on silica gel

ORD record

ord-557a48af25d444cf849f87ea4e754ccc

Source dataset

uspto-grants-2012_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08158671B2