5-Bromo-2-chloro-3-nitropyridine → 4-Bromo-7-chloro-1H-pyrrolo(2,3-c)pyridine

Temperature

-70 °C

To a solution of 5-bromo-2-chloro-3-nitro-pyridine (7 g) in dry tetrahydrofuran (150 ml) at −70° C. under an atmosphere of nitrogen was added dropwise a solution of vinylmagnesium bromide (1.0M in tetrahydrofuran; 94.5 ml) over 1 h. The solution was stirred at −70° C. for 1 h and then quenched with saturated ammonium chloride (150 ml) and the aqueous was extracted twice with ethyl acetate. The combined organics were dried (MgSO4) and evaporated to give a deep red oil. The residue was triturated with diethyl ether (100 ml) and the solid was then filtered off, sucked dry then dried at 40° C. under vacuum to afford the title compound (1.75 g).

1. customquenched with saturated ammonium chloride (150 ml)
2. extractionthe aqueous was extracted twice with ethyl acetate
3. dry with materialThe combined organics were dried (MgSO4)
4. customevaporated
5. customto give a deep red oil
6. customThe residue was triturated with diethyl ether (100 ml)
7. filtrationthe solid was then filtered off
8. customsucked dry
9. customthen dried at 40° C. under vacuum

ORD record

ord-431b470d792447fdaa0f09cc6918b5e8

Source dataset

uspto-grants-2009_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07589206B2