Triethylamine → 2,6-Dichloro-3-methylpyridine

HRID 505385Notes

Reaction equation

HRID 505385 reaction equation
[Cl:1][C:2]1[C:7]([CH3:8])=[CH:6][CH:5]=[CH:4][N+:3]=1[O-].C(N(CC)CC)C.P(Cl)(Cl)([Cl:19])=O.[OH-].[Na+]>ClCCl.O>[Cl:1][C:2]1[C:7]([CH3:8])=[CH:6][CH:5]=[C:4]([Cl:19])[N:3]=1

Participants

7

Reactant 4

HCID 8471TriethylamineHCID 14798Sodium HydroxideHCID 24813Phosphorus oxychlorideHCID 134316222-Chloro-3-methyl-1-oxo-1lambda~5~-pyridine

Product 1

HCID 8170882,6-Dichloro-3-methylpyridineYield 34.2%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6344DichloromethaneSolvent2×

Procedure

2-Chloro-3-methylpyridine 1-oxide (9.00 g, 62.7 mmol) and triethylamine (10.4 ml, 75.2 mmol) were dissolved in dichloromethane (70 ml), and a solution of phosphorus oxychloride (7 ml, 75.3 mmol) in dichloromethane (40 ml) was added dropwise at 0° C. After stirring for 3 hours while elevating reaction temperature to room temperature, the reaction mixture was stirred under reflux for 1 hour. After the reaction was completed, water (30 ml) was added and the reaction mixture was neutralized with a sodium hydroxide solution, and after extracted with dichloromethane (70 ml), dried over magnesium sulfate. The solvent was evaporated and purified by silica gel column chromatography (eluting solvent: ethyl acetate/n-hexane=3/100), thereby yielding the title compound (3.47 g) as a white solid 10:3 mixture with 2,4-dichloro-3-methylpyridine.

Workup

  1. stirringthe reaction mixture was stirred
  2. temperatureunder reflux for 1 hour
  3. extractionafter extracted with dichloromethane (70 ml)
  4. dry with materialdried over magnesium sulfate
  5. customThe solvent was evaporated
  6. custompurified by silica gel column chromatography (eluting solvent: ethyl acetate/n-hexane=3/100)

Sources & evidence

ORD record
ord-11c8505cb0f04b76b84398dbdf22bb27
Source dataset
uspto-grants-2010_08
Patent number
US07781452B2

Reaction notes

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