Hydrogen Bromide → 3-Bromo-5-(trifluoromethyl)pyridine

Temperature

60 °C

A solution of sodium nitrite (402 mg, 5.83 mmol) in water (6.8 mL) was added slowly to a suspension of 5-(trifluoromethyl)pyridin-3-amine (947 mg, 5.55 mmol) in hydrogen bromide (48% aqueous solution, 1.57 mL) in ice-water bath. After being stirred for 10 min, the resulting orange diazo solution was directly but slowly transferred to a stirring mixture of copper(I) bromide (876 mg, 6.11 mmol) and hydrogen bromide (48% aqueous solution, 0.38 mL). The resulting brown mixture was heated at 60° C. for 1 h. After cooling to room temperature, the mixture was diluted with methylene chloride, washed with 50% NaOH (until pH =11), and water. The aqueous layer was back extracted with methylene chloride. The combined organic extracts were carefully concentrated under vacuum to provide crude product without purification.

1. temperatureAfter cooling to room temperature
2. washwashed with 50% NaOH (until pH =11), and water
3. extractionThe aqueous layer was back extracted with methylene chloride
4. concentrationThe combined organic extracts were carefully concentrated under vacuum
5. customto provide crude product
6. customwithout purification

ORD record

ord-48b467efc96d4a5aa8ca22dc271ff1a6

Source dataset

uspto-grants-2009_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07618970B2