Hydrazine → 1H-pyrazolo(3,4-b)pyridine

Temperature

150 °C

2-Chloro-3-formylpyridine (15.02 g, 106 mmol, 1 equiv), hydrazine (10 mL, excess), and dioxane (90 mL) were combined in a sealed tube and heated at 150° C. for 16 hr. After cooling to room temperature, the solvent was evaporated in vacuo to provide a crude residue which was diluted with dichloromethane (600 mL). The organic solution was washed with water (50 mL), brine (50 mL) and dried over anhydrous sodium sulfate. The solvent was removed in vacuo to provide 1H-pyrazolo[3,4-b]pyridine as a yellow powder which was used without further purification: LCMS (ES) M+H 120.3, Rf 0.20 min (Agilent Zorbax SB-C18, 2.1×50 mm, 5μ, 35° C., 1 ml/min flow rate, a 2.5 min gradient of 20% to 100% B with a 1.1 min wash at 100% B; A=0.1% formic acid /5% acetonitrile /94.9% water, B=0.1% formic acid /5% water/94.9% acetonitrile).

1. temperatureAfter cooling to room temperature
2. customthe solvent was evaporated in vacuo
3. customto provide a crude residue which
4. washThe organic solution was washed with water (50 mL), brine (50 mL)
5. dry with materialdried over anhydrous sodium sulfate
6. customThe solvent was removed in vacuo

ORD record

ord-160d05d97f9e4868980756491e54774a

Source dataset

uspto-grants-2009_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07524845B2