2-Chloro-3-nitropyridine → 7-Chloro-1H-pyrrolo[2,3-c]pyridine

Temperature

-78 °C

2-Chloro-3-nitropyridine 22e (5.0 g) was dissolved in dry THF (200 ml). After the solution was cooled down to −78° C., an excess of vinyl magnesium bromide (1.0 M in THF, 100 ml) was added. Then, the reaction was left at −20° C. for eight hours before being quenched with 20% NH4Cl (150 ml). The aqueous phase was extracted with EtOAc (3×150 ml). The combined organic layer was dried over MgSO4. After filtration and concentration, the crude product was purified by silica gel column chromatography to afford 1.5 g of 7-chloro-6-azaindole 1e in 31% yield.

1. custombefore being quenched with 20% NH4Cl (150 ml)
2. extractionThe aqueous phase was extracted with EtOAc (3×150 ml)
3. dry with materialThe combined organic layer was dried over MgSO4
4. filtrationAfter filtration and concentration
5. customthe crude product was purified by silica gel column chromatography

ORD record

ord-ad0ffa5f287d47419e66a71ebd0496d1

Source dataset

uspto-grants-2010_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07745625B2