Acetic Anhydride → 1-Acetylpyrazolo[3,4-c]pyridine

To a suspension of 3-acetylamino-4-methylpyridine (301.5 mg, 2.0 mmol, 1 equiv) in toluene (3 mL) was added tert-butyl nitrite (t-BuONO) (420 μL, 3.2 mmol, 1.6 equiv), acetic anhydride (560 μL, 6.0 mmol, 3 equiv) and potassium acetate (235.2 mg, 2.4 mmol, 1.2 equiv). The resultant mixture was heated at 80° C. for 2 hours, cooled to room temperature, and diluted with ethyl acetate (200 mL). The mixture was washed with saturated sodium bicarbonate solution (50 mL), water (50 mL) and brine (50 mL). The organic layer was dried over sodium sulfate and concentrated in vacuo to provide a crude residue. The residue was purified by flash chromatography (silica, 15% ethyl acetate/hexane to 50% ethyl acetate/hexane) to give 1-pyrazolo[3,4-c]pyridin-1-yl-ethanone (20.2 mg) which was used without further purification.

1. washThe mixture was washed with saturated sodium bicarbonate solution (50 mL), water (50 mL) and brine (50 mL)
2. dry with materialThe organic layer was dried over sodium sulfate
3. concentrationconcentrated in vacuo
4. customto provide a crude residue
5. customThe residue was purified by flash chromatography (silica, 15% ethyl acetate/hexane to 50% ethyl acetate/hexane)

ORD record

ord-04d3b9ec478944b8a8eddf7ffa9ec078

Source dataset

uspto-grants-2009_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07524845B2