Phosphorus tribromide → 6-(1-Bromoethyl)quinoxaline

HRID 642877Notes

Reaction equation

HRID 642877 reaction equation
O[CH:2]([C:4]1[CH:5]=[C:6]2[C:11](=[CH:12][CH:13]=1)[N:10]=[CH:9][CH:8]=[N:7]2)[CH3:3].P(Br)(Br)[Br:15]>CCOCC>[Br:15][CH:2]([C:4]1[CH:5]=[C:6]2[C:11](=[CH:12][CH:13]=1)[N:10]=[CH:9][CH:8]=[N:7]2)[CH3:3]

Participants

4

Reactant 2

HCID 24614Phosphorus tribromideHCID 451216111-(Quinoxalin-6-yl)ethanol

Product 1

HCID 585927736-(1-Bromoethyl)quinoxalineYield 37%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Procedure

To a solution of 6-(1-hydroxyethyl)quinoxaline (0.4 g, 0.23 mMol) in ether (4 mL) and hexanes (2 mL) at zero degrees was added phosphorus tribromide (0.196 mL, 2.07 mMol) and the mixture stirred at zero degrees for one hour and then allowed to warm to room temperature. After two hours at room temperature the reaction mixture was poured over ice and then partitioned between ethyl acetate (100 mL) and water (100 mL). The aqueous layer was discarded and the organics washed with saturated sodium bicarbonate, then dried (MgSO4), and concentrated to dryness to yield 20 mg (37% yield) of 6-(1-bromo-ethyl)-quinoxaline as a light yellow oil. 1H NMR (CDCl3): δ=8.79 (m, 2H), 8.06 (d, 1H, J=9.0 Hz), 8.04 (d, 1H, J=2.2 Hz), 7.85 (dd, 1H, J=9.0, 2.2 Hz), 5.34 (q, 1H, J=6.9 Hz), 2.10 (d, 3H, J=6.9 Hz).

Workup

  1. additionAfter two hours at room temperature the reaction mixture was poured over ice
  2. custompartitioned between ethyl acetate (100 mL) and water (100 mL)
  3. washthe organics washed with saturated sodium bicarbonate
  4. dry with materialdried (MgSO4)
  5. concentrationconcentrated to dryness

Sources & evidence

ORD record
ord-1ad8d254dcd54f95a72ac283ae2d3989
Source dataset
uspto-grants-2010_04
Patent number
US07696210B2

Reaction notes

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