Acetic Anhydride → 4-ethoxy-1H-pyridin-2-one

Temperature

25 °C

A mixture of 4-ethoxypyridine 1-oxide (20 g, 144 mmol) in Ac2O (200 mL, 7.836 mol) was heated to refluxed for 4 h. Then, the solvent was removed in vacuo, and the residue was dissolved in MeOH (50 mL) and water (50 mL) and stirred at 25° C. for 16 h. The mixture was then concentrated and the crude material was purified by silica column chromatography (DCM/MeOH=10:1). All fractions found to contain product by TLC (DCM/MeOH=10:1, Rf=0.6) were combined and concentrated to yield a dark yellow solid of 4-ethoxypyridin-2-ol (17 g, 104 mmol, 72% yield). 1H NMR (400 MHz, MeOH-d4) δ 8.20 (d, J=7.6 Hz, 2H), 7.12 (d, J=7.6 Hz, 2H), 4.18 (q, J=7.2 Hz, 2H), 1.42 (t, J=6.8 Hz, 3H); ES-LCMS m/z: 140.0 (M+H).

1. temperaturewas heated
2. temperatureto refluxed for 4 h
3. customThen, the solvent was removed in vacuo
4. dissolutionthe residue was dissolved in MeOH (50 mL)
5. concentrationThe mixture was then concentrated
6. customthe crude material was purified by silica column chromatography (DCM/MeOH=10:1)
7. concentrationconcentrated

ORD record

ord-9987eea31ef4421fb8741ebdaec8e82b

Source dataset

uspto-grants-2016_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09382238B2