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

HRID 722241Notes

Reaction equation

HRID 722241 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). HPLC Rt: 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-45bba78c55f74a5c961f2836ef82292d
Source dataset
uspto-grants-2006_11
Patent number
US07138402B2

Reaction notes

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