Phosphorus tribromide → 2-Chloro-5-fluorobenzyl bromide

HRID 607313Notes

Reaction equation

HRID 607313 reaction equation
[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([F:8])=[CH:4][C:3]=1[CH2:9]O.P(Br)(Br)[Br:12].C(=O)(O)[O-].[Na+]>ClCCl>[Br:12][CH2:9][C:3]1[CH:4]=[C:5]([F:8])[CH:6]=[CH:7][C:2]=1[Cl:1]

Participants

5

Reactant 3

HCID 24614Phosphorus tribromideHCID 516892Sodium BicarbonateHCID 2773605(2-Chloro-5-fluorophenyl)methanol

Product 1

HCID 27736232-Chloro-5-fluorobenzyl bromideYield 82.7%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To a solution of (2-chloro-5-fluoro-phenyl)-methanol (5.0 g, 31.1 mmol) in dichloromethane (40 mL) was added drop wise phosphorus tribromide (87 g, 31.1 mmol). The mixture was stirred at room temperature for 16 h. The reaction was poured onto ice/water. The aqueous phase was made basic with sodium bicarbonate. The aqueous phase was extracted with dichloromethane. The organic phase was concentrated under reduced pressure. The residue was purified by silica gel chromatography eluting with (hexanes/ethyl acetate 90:10) to give the title compound (5.75 g, 82.5%).

Workup

  1. additionThe reaction was poured onto ice/water
  2. extractionThe aqueous phase was extracted with dichloromethane
  3. concentrationThe organic phase was concentrated under reduced pressure
  4. customThe residue was purified by silica gel chromatography
  5. washeluting with (hexanes/ethyl acetate 90:10)

Sources & evidence

ORD record
ord-09fa35d3b6fb49a18d207ff5c48622fd
Source dataset
uspto-grants-2011_03
Patent number
US07915411B2

Reaction notes

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