3,5-Dibromopyridine → 3-Bromo-5-(propan-2-yloxy)pyridine

HRID 1168939Notes

Reaction equation

HRID 1168939 reaction equation
[K].[CH3:2][CH:3]([CH3:5])[O-:4].[K+].Br[C:8]1[CH:9]=[N:10][CH:11]=[C:12]([Br:14])[CH:13]=1>CC(O)C.[Cu]>[Br:14][C:12]1[CH:13]=[C:8]([O:4][CH:3]([CH3:5])[CH3:2])[CH:9]=[N:10][CH:11]=1

Participants

6

Reactant 3

HCID 693693,5-DibromopyridineHCID 5462222PotassiumHCID 23663646Potassium propan-2-olate

Product 1

HCID 105848083-Bromo-5-(propan-2-yloxy)pyridineYield 71.2%

Reagents, catalysts & solvents 2

HCID 23978CopperCatalystHCID 3776IsopropanolSolvent

Procedure

Potassium metal (6.59 g, 168.84 mmol) was dissolved in dry 2-propanol (60.0 mL) under nitrogen. The resulting potassium isopropoxide was heated with 3,5-dibromopyridine (20.00 g, 84.42 mmol) and copper powder (1 g, 5% by weight of 3,5-dibromopyridine) at 140° C. (oil bath temperature) in a sealed glass tube for 14 h. The reaction mixture was cooled to ambient temperature and extracted with diethyl ether (4×200 mL). The combined ether extracts were dried over sodium sulfate, filtered, and concentrated by rotary evaporation. The crude product obtained was purified by column chromatography over aluminum oxide, eluting with ethyl acetate-hexane (1:9, v/v). Selected fractions were combined and concentrated by rotary evaporation, producing a pale-yellow oil (12.99 g, 71.2%).

Workup

  1. extractionextracted with diethyl ether (4×200 mL)
  2. dry with materialThe combined ether extracts were dried over sodium sulfate
  3. filtrationfiltered
  4. concentrationconcentrated by rotary evaporation
  5. customThe crude product obtained
  6. customwas purified by column chromatography over aluminum oxide
  7. washeluting with ethyl acetate-hexane (1:9, v/v)
  8. concentrationconcentrated by rotary evaporation

Sources & evidence

ORD record
ord-4e72c602c3ac4155862ccf6ac0f7860c
Source dataset
uspto-grants-2003_09
Patent number
US06627648B1

Reaction notes

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