Iodine → 1-Quinoxalin-2-yl-but-3-yn-1-ol

HRID 422414Notes

Reaction equation

HRID 422414 reaction equation
[Mg].II.[CH2:4](Br)[C:5]#[CH:6].[N:8]1[C:17]2[C:12](=[CH:13][CH:14]=[CH:15][CH:16]=2)[N:11]=[CH:10][C:9]=1[CH:18]=[O:19].[NH4+].[Cl-]>CCOCC.C1COCC1>[N:8]1[C:17]2[C:12](=[CH:13][CH:14]=[CH:15][CH:16]=2)[N:11]=[CH:10][C:9]=1[CH:18]([OH:19])[CH2:6][C:5]#[CH:4]

Participants

8

Reactant 5

HCID 807IodineHCID 7842Propargyl bromideHCID 25517Ammonium ChlorideHCID 594088Quinoxaline-2-carbaldehydeHCID 5462224Magnesium

Product 1

HCID 866302471-Quinoxalin-2-yl-but-3-yn-1-ol

Reagents, catalysts & solvents 2

HCID 3283Diethyl EtherSolvent2×HCID 8028TetrahydrofuranSolvent

Procedure

To a mixture of magnesium (229 mg, 9.41 mmol), mercuric chloride (13 mg, 47 μmol) and few crystals of iodine in Et2O (1.5 mL), a solution of propargyl bromide (0.53 mL, 5.88 mmol) in Et2O (4.5 mL) was added slowly in order to maintain a reflux. The reaction mixture was stirred 1 hour and added to a solution of quinoxaline-2-carbaldehyde (500 mg, 3.16 mmol) in THF (2 mL). The resulting reaction mixture was stirred at 0° C. for 30 min, at room temperature for 30 min and was poured onto saturated NH4Cl solution. The aqueous phase was extracted with Et2O. The aqueous phase was washed with water, brine, dried over MgSO4, filtered and evaporated. The crude residue was purified by C18 flash chromatography (H2O/acetonitrile 100:0 to 80:20) to yield 90 mg (0.45 mmol, 14%) of 1-quinoxalin-2-yl-but-3-ynyl-ol as a yellow oil.

Workup

  1. temperatureto maintain a reflux
  2. customThe resulting reaction mixture
  3. stirringwas stirred at 0° C. for 30 min, at room temperature for 30 min
  4. extractionThe aqueous phase was extracted with Et2O
  5. washThe aqueous phase was washed with water, brine
  6. dry with materialdried over MgSO4
  7. filtrationfiltered
  8. customevaporated
  9. customThe crude residue was purified by C18 flash chromatography (H2O/acetonitrile 100:0 to 80:20)
  10. customto yield 90 mg (0.45 mmol, 14%) of 1-quinoxalin-2-yl-but-3-ynyl-ol as a yellow oil

Sources & evidence

ORD record
ord-96286cff0c7b408389a3c9e7c903bf84
Source dataset
uspto-grants-2012_01
Patent number
US08101637B2

Reaction notes

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