Acetic Anhydride → 4-(2,4-difluorobenzyloxy)-1H-pyridin-2-one

HRID 1831913Notes

Reaction equation

HRID 1831913 reaction equation
[F:1][C:2]1[CH:16]=[C:15]([F:17])[CH:14]=[CH:13][C:3]=1[CH2:4][O:5][C:6]1[CH:11]=[CH:10][N+:9]([O-])=[CH:8][CH:7]=1.C(OC(=O)C)(=[O:20])C>>[F:1][C:2]1[CH:16]=[C:15]([F:17])[CH:14]=[CH:13][C:3]=1[CH2:4][O:5][C:6]1[CH:11]=[CH:10][NH:9][C:8](=[O:20])[CH:7]=1

Participants

3

Reactant 2

HCID 7918Acetic AnhydrideHCID 220502194-(2,4-Difluorobenzyloxy)pyridine-1-oxide

Product 1

HCID 220503904-(2,4-difluorobenzyloxy)-1H-pyridin-2-oneYield 31%

Procedure

A solution of 4-(2,4-difluorobenzyloxy)pyridine-1-oxide (13.4 g, 57 mmol) in acetic anhydride (30 mL) was stirred at reflux for 4 h. The solvent was removed under reduced pressure, the residue was diluted with 1:1 MeOH/water (60 mL), and the mixture was stirred at room temperature for 1 h. The solvent was removed under reduced pressure. Purification by flash column chromatography (silica, eluent methylene chloride to 9:1 methylene chloride/methanol) provided 4-(2,4-difluorobenzyloxy)-1H-pyridin-2-one as a light brown solid (4.2 g, 31%): 1H NMR (300 MHz, CDCl3) δ 7.43 (q, J=8 Hz, 1H), 7.23 (d, J=7 Hz, 1H), 6.91-6.87 (m, 2H), 6.02 (dd, J=8, 2 Hz, 1H), 5.97 (d, J=2 Hz, 1H), 5.03 (s, 2H).

Workup

  1. temperatureat reflux for 4 h
  2. customThe solvent was removed under reduced pressure
  3. additionthe residue was diluted with 1:1 MeOH/water (60 mL)
  4. customThe solvent was removed under reduced pressure
  5. customPurification by flash column chromatography (silica, eluent methylene chloride to 9:1 methylene chloride/methanol)

Sources & evidence

ORD record
ord-3f110f26450942f9b5a124df7f5e8598
Source dataset
uspto-grants-2006_06
Patent number
US07067540B2

Reaction notes

Loading…