Bromine → 3-Bromo-5-chloro-2-methoxypyridine

HRID 280187Notes

Reaction equation

HRID 280187 reaction equation
C([O-])(=O)C.[Na+].[Cl:6][C:7]1[CH:8]=[CH:9][C:10]([O:13][CH3:14])=[N:11][CH:12]=1.[Br:15]Br>C(O)(=O)C>[Br:15][C:9]1[C:10]([O:13][CH3:14])=[N:11][CH:12]=[C:7]([Cl:6])[CH:8]=1

Participants

5

Reactant 3

HCID 24408BromineHCID 517045Sodium AcetateHCID 47382765-Chloro-2-methoxypyridine

Product 1

HCID 135677513-Bromo-5-chloro-2-methoxypyridine

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent2×

Conditions

Temperature
80 °C

Procedure

To a stirred suspension of 2.5 g of anhydrous sodium acetate in 10 ml of acetic acid was added 4.3 g of 5-chloro-2-methoxypyridine followed by a solution of 3.1 ml of bromine in 10 ml of acetic acid. The mixture was warmed to 80° C. for 6 hours and then allowed to cool and stirred at 23° C. for 64 hours. It was then partitioned between ether and water and the resulting ether layer was washed with aqueous 1N sodium hydroxide solution and then with aqueous 5% sodium bisulfite solution, dried over potassium carbonate and concentrated at reduced pressure to leave a residual brown solid. This residue was bulb-to-bulb distilled with the material distilling at 140°-150° C. at 20 torr collected to give 3-bromo-5-chloro-2-methoxypyridine as a solid melting at about 45°-47.5° C.

Workup

  1. temperatureto cool
  2. customIt was then partitioned between ether and water
  3. washthe resulting ether layer was washed with aqueous 1N sodium hydroxide solution
  4. dry with materialwith aqueous 5% sodium bisulfite solution, dried over potassium carbonate
  5. concentrationconcentrated at reduced pressure
  6. customto leave a residual brown solid
  7. distillationdistilled with the material
  8. distillationdistilling at 140°-150° C. at 20 torr
  9. customcollected

Sources & evidence

ORD record
ord-a57e399a64054ad68499af284a975daa
Source dataset
uspto-grants-1986_05
Patent number
US04588733

Reaction notes

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