Hydrochloric Acid → 5-bromo-1H-pyrrolo[2,3-b]pyridine

Temperature

80 °C

To a solution of 5-bromo-3-(2-(trimethylsilyl)ethynyl)pyridin-2-amine (B-7-2) (9.5 g, 35.3 mmol) in t-BuOH (100 mL) was added t-BuOK (10.5 g, 141.3 mmol). The mixture was stirred at 80° C. for 20 hours. TLC (Petroleum ether: EtOAc=5:1) showed that the reaction was complete. Then the mixture was cooled to room temperature. Concentrated hydrochoric acid (50 mL) was added to the mixture. Then the mixture was heated to reflux for 8 hours. TLC (Petroleum ether: EtOAc=5:1) showed that the reaction was complete. The mixture was cooled to room temperature and poured into water (100 mL). The mixture was filtered through a bed of Celite. The filtrate was diluted with water (100 mL) and made basic by the addition of 50% sodium hydroxide. The mixture was extracted with EtOAc (150 mL×3). The organic layers were washed with water (100 mL) and saturated sodium chloride (100 mL), dried over sodium sulfate and concentrated under reduced pressure to afford 5-bromo-1H-pyrrolo[2,3-b]pyridine (B-7-3) (6.2 g, 88.6%) as a light yellow solid.

1. temperatureThen the mixture was cooled to room temperature
2. temperatureThen the mixture was heated
3. temperatureto reflux for 8 hours
4. temperatureThe mixture was cooled to room temperature
5. filtrationThe mixture was filtered through a bed of Celite
6. additionThe filtrate was diluted with water (100 mL)
7. additionmade basic by the addition of 50% sodium hydroxide
8. extractionThe mixture was extracted with EtOAc (150 mL×3)
9. washThe organic layers were washed with water (100 mL) and saturated sodium chloride (100 mL)
10. dry with materialdried over sodium sulfate
11. concentrationconcentrated under reduced pressure

ORD record

ord-bd32561e0b2746f2addea92603f189b6

Source dataset

uspto-grants-2010_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07772246B2