Chloroacetaldehyde → HCID 57648848, compound

To a solution of 3-Amino-1H-pyridin-2-one (2.0 g, 18.7 mmol) in water (2 mL) was added 15% HCl (10 mL, 18 mmol) followed by ammonium thiocyanate (1.5 g, 18 mmol) and the mixture was heated to reflux for two hours. Upon cooling the intermediate thiourea was found to precipitate as a red-brown solid. The mixture was filtered and the solid washed with water (5 mL). To a solution of the thiourea (1.3 g, 7.7 mmol) in EtOH (20 mL) and water (5 mL) was added chloroacetaldehyde (2.3 mL), 16.4 mmol) and the mixture was heated to reflux for four hours. On cooling, the mixture was diluted with EtOAc (30 mL) and washed with 10% NaHCO3 and brine. The organic phase was dried over MgSO4 and concentrated in vacuo. The residue was purified by flash column chromatography (100% EtOAc) to afford the title compound as a pale green solid (1.43 g, 40%): 1H NMR (400 MHz, CDCl3) δ 1.6 (1H, s), 6.45 (1H, t), 6.75 (1H, s), 7.05-7.10 (1H, m), 7.40-7.42 (1H, m), 8.35-8.5 (2H, m); M+H 194.1, M−H 192.1.

1. temperaturethe mixture was heated
2. temperatureto reflux for two hours
3. customto precipitate as a red-brown solid
4. filtrationThe mixture was filtered
5. washthe solid washed with water (5 mL)
6. temperaturewas heated
7. temperatureto reflux for four hours
8. temperatureOn cooling
9. washwashed with 10% NaHCO3 and brine
10. dry with materialThe organic phase was dried over MgSO4
11. concentrationconcentrated in vacuo
12. customThe residue was purified by flash column chromatography (100% EtOAc)

ORD record

ord-338eec8af5fd4624aa679efe9a13dc1f

Source dataset

uspto-grants-2011_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07960415B2