Acetic Anhydride → HCID 71128531, compound

Temperature

80 °C

A solution of N-(5-bromo-2-methylpyridin-3-yl)acetamide (2.8 g, 12 mmol) and potassium acetate (3.59 g, 36.6 mmol) in toluene (50 mL) was heated at 80° C. under nitrogen. After 30 min, 2-methyl-2-nitropropane (3.77 g, 36.6 mmol) and acetic anhydride (3.73 g, 36.6 mmol) were added, and the resulting mixture was stirred at 80° C. for another 18 h. The reaction mixture was concentrated in vacuo, and the residue was diluted with water (50 mL). The aqueous mixture was extracted with ethyl acetate (3×60 mL). The collected organic extractions were concentrated in vacuo. Purification by flash column chromatography (5→10% ethyl acetate in petroleum ether) afforded 1-(6-bromo-1H-pyrazolo[4,3-b]pyridin-1-yl)ethanone (1.4 g, 48.% yield). 1H NMR (400 MHz, Chloroform-d) δ 8.90 (s, 1 H), 8.75 (s, 1 H), 8.32 (s, 1 H), 2.79 (s, 3 H).

1. concentrationThe reaction mixture was concentrated in vacuo
2. additionthe residue was diluted with water (50 mL)
3. extractionThe aqueous mixture was extracted with ethyl acetate (3×60 mL)
4. extractionThe collected organic extractions
5. concentrationwere concentrated in vacuo
6. customPurification by flash column chromatography (5→10% ethyl acetate in petroleum ether)

ORD record

ord-0137b78479f14421a6734806f50fe255

Source dataset

uspto-grants-2016_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09365583B2