2-Bromopyridine → 2-(2'-Thienyl)pyridine

HRID 2081750Notes

Reaction equation

HRID 2081750 reaction equation
[S:1]1[CH:5]=[CH:4][CH:3]=[CH:2]1.C([Li])CCC.Br[C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][N:13]=1>C1COCC1.[Cl-].[Zn+2].[Cl-]>[N:13]1[CH:14]=[CH:15][CH:16]=[CH:17][C:12]=1[C:2]1[S:1][CH:5]=[CH:4][CH:3]=1

Participants

6

Procedure

To a solution of thiophene (4.7 mL, 59.4 mmole) at 0° C. was added 2.5M n-butyllithium (24 mL, 59.4 mmole) dropwise via syringe. The solution was stirred 3 h and was transferred via cannula into a stirred solution of zinc chloride (8.6 g, 63.4 mmole) in 60 mL THF at room temperature. This solution was stirred for 1 h and was transferred via cannula into a stirred solution of 2-bromopyridine (3.8 mL, 39.6 mmole) and tetrakis-triphenylphosphine palladium (0.22 g, 0.2 mmole) in 100 mL of THF. The solution was stirred overnight at room temperature and was then quenched with saturate ammonium chloride solution (100 mL) and extracted with ether (3×100 mL). The ether extracts were washed with brine (1×100 mL), dried over MgSO4, filtered and concentrated to yield 8.4 g of crude residue. The material was chromatographed (silica gel, 10% ether/hexanes) to yield 5.0 g (78%) of a pale yellow solid.

Workup

  1. stirringThis solution was stirred for 1 h
  2. stirringThe solution was stirred overnight at room temperature
  3. customwas then quenched with saturate ammonium chloride solution (100 mL)
  4. extractionextracted with ether (3×100 mL)
  5. washThe ether extracts were washed with brine (1×100 mL)
  6. dry with materialdried over MgSO4
  7. filtrationfiltered
  8. concentrationconcentrated
  9. customto yield 8.4 g of crude residue
  10. customThe material was chromatographed (silica gel, 10% ether/hexanes)

Sources & evidence

ORD record
ord-865efd57c3fc4e8fa1d83829a6e880b2
Source dataset
uspto-grants-1993_02
Patent number
US05185363

Reaction notes

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