Hydrogen Bromide → 5-Fluoro-2-methoxybenzyl bromide

HRID 736032Notes

Reaction equation

HRID 736032 reaction equation
[BrH:1].[F:2][C:3]1[CH:4]=[CH:5][C:6]([O:11][CH3:12])=[C:7]([CH2:9]O)[CH:8]=1>C(Cl)(Cl)Cl>[Br:1][CH2:9][C:7]1[CH:8]=[C:3]([F:2])[CH:4]=[CH:5][C:6]=1[O:11][CH3:12]

Participants

4

Reactant 2

HCID 260Hydrogen BromideHCID 22014996(5-Fluoro-2-methoxyphenyl)methanol

Product 1

HCID 201117455-Fluoro-2-methoxybenzyl bromide

Reagents, catalysts & solvents 1

HCID 6212ChloroformSolvent

Procedure

Add Sodium borohydride (540 mg, 13.95 mmol) in portions to a solution of 5-Fluoro-2-methoxy-benzaldehyde (2.15 g, 13.94 mmol) in absolute EtOH (20 ml) and stir at room temperature. After 1 h, evaporate the solvent, dilute the residue in CH2Cl2 and treat with aqueous 3M HCl. Separate the phases, wash the organic one twice with H2O, dry over Na2SO4 and concentrate at vacuum to obtain pure (5-Fluoro-2-methoxy-phenyl)-methanol as white solid. Add aqueous concentrated HBr (15 ml) to a solution of (5-Fluoro-2-methoxy-phenyl)-methanol (1.9 g, 12.17 mmol) in CHCl3 (10 ml) and stir at room temperature. After 1 h, separate the phases, wash the aqueous one with CH2Cl2, combine organic phases, wash with H2O, dry over Na2SO4 and concentrate at vacuum to obtain a residue. Purify the residue by column chromatography on silica gel eluting with hexane to afford 2-Bromomethyl-4-fluoro-1-methoxy-benzene as white solid. 1H-NMR (CDCl3, 200 Mz): δ 7.06 (dd, J=3.0 and 8.6 Hz, 1H), 6.98 (m, 1H), 6.81 (dd, J=4.4 and 9.0 Hz, 1H), 4.50 (s, 2H), 3.87 (s, 3H).

Workup

  1. customseparate the phases
  2. washwash the aqueous one with CH2Cl2
  3. washwash with H2O
  4. dry with materialdry over Na2SO4
  5. concentrationconcentrate at vacuum
  6. customto obtain a residue
  7. customPurify the residue by column chromatography on silica gel eluting with hexane

Sources & evidence

ORD record
ord-6de5b070eecf4bc19eee40a655577ebf
Source dataset
uspto-grants-2009_09
Patent number
US07595315B2

Reaction notes

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