Ethyl Acetate → 4-Bromo-2,3,5-trimethyl-1-oxo-1lambda~5~-pyridine

HRID 857932Notes

Reaction equation

HRID 857932 reaction equation
[N+:1]1([O-:10])[CH:6]=[C:5]([CH3:7])[CH:4]=[C:3]([CH3:8])[C:2]=1[CH3:9].C([O-])([O-])=O.[K+].[K+].[Br:17]Br.CCOC(C)=O>C(Cl)(Cl)(Cl)Cl.CO.CCOC(C)=O>[Br:17][C:4]1[C:5]([CH3:7])=[CH:6][N+:1]([O-:10])=[C:2]([CH3:9])[C:3]=1[CH3:8]

Participants

7

Reactant 4

HCID 8857Ethyl AcetateHCID 11430Potassium CarbonateHCID 24408BromineHCID 104869072,3,5-Trimethyl-1-oxidopyridin-1-ium

Product 1

HCID 167371384-Bromo-2,3,5-trimethyl-1-oxo-1lambda~5~-pyridineYield 51%

Reagents, catalysts & solvents 2

HCID 5943Carbon TetrachlorideSolventHCID 21584119Ethylacetate methanolSolvent

Procedure

2,3,5-collidine-N-oxide (1.3 g, 10 mmol) and K2CO3 (2.9 g, 20 mmol) were suspended in 10 mL of CCl4. Bromine (1 mL, 20 mmol) was added dropwise, and the reaction mixture was heated to reflux for 2 h. Work-up (EtOAc) and flash chromatography (10% MeOH/EtOAc) afforded the title compound as a solid (1.05 g, 51% yield). R.t.: 5.24 min. 1H-NMR (CDCl3): δ 8.06 (s, 1H), 2.56 (s, 3H), 2.43 (s, 3H), 2.31 (s, 3H). m/z (%) 216.2 (M+1, 100%), 218.2 (M+3, 100%). Rf (20% MeOH/EtOAc): 0.45.

Workup

  1. temperaturethe reaction mixture was heated
  2. temperatureto reflux for 2 h

Sources & evidence

ORD record
ord-94db0e9f975644bebae7962b3a99ddd2
Source dataset
uspto-grants-2006_12
Patent number
US07148228B2

Reaction notes

Loading…