Sodium Thiosulfate → 4-Cyano-3-fluorobenzyl bromide

HRID 1987340Notes

Reaction equation

HRID 1987340 reaction equation
[F:1][C:2]1[CH:9]=[C:8]([CH3:10])[CH:7]=[CH:6][C:3]=1[C:4]#[N:5].N(C1(C#N)CCCCC1)=NC1(C#N)CCCCC1.C1C(=O)N([Br:36])C(=O)C1.[O-]S([O-])(=S)=O.[Na+].[Na+]>C(Cl)(Cl)(Cl)Cl.O>[Br:36][CH2:10][C:8]1[CH:7]=[CH:6][C:3]([C:4]#[N:5])=[C:2]([F:1])[CH:9]=1

Participants

7

Reactant 4

HCID 24477Sodium ThiosulfateHCID 67184N-bromobutanimideHCID 749781,1'-Azobis(cyclohexanecarbonitrile)HCID 27784432-Fluoro-4-methylbenzonitrile

Product 1

HCID 27784664-Cyano-3-fluorobenzyl bromideYield 65.1%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 5943Carbon TetrachlorideSolvent

Procedure

To a solution of 2-fluoro-4-methyl-benzonitrile (1.45 g, 10.7 mmol) in CCl4 (100 mL) was added 1,1′-azobis(cyclohexanecarbonitrile) (0.240 g, 0.982 mmol) and NBS (2.19 g, 12.3 mmol). The mixture was stirred and heated at reflux overnight, and then cooled to room temperature. A solution of Na2S2O3 (5 g) in H2O (100 mL) was added, and the organic layer was collected. The aqueous layer was extracted with CH2Cl2 (3×50 mL), and the extracts were combined and dried over Na2SO4. After filtration the solvent was removed by evaporation under vacuum, and the residue was purified on silica gel column (1:10 EtOAc/hexanes), affording 4-bromomethyl-2-fluoro-benzonitrile as a pale yellow oil (1.49 g, 65%). 1H NMR (CDCl3) δ 4.45 (s, 2H), 7.24-7.30 (m, 2H), 7.60 (dd, 1H, J=6.3, 8.1 Hz).

Workup

  1. temperatureheated
  2. temperatureat reflux overnight
  3. customthe organic layer was collected
  4. extractionThe aqueous layer was extracted with CH2Cl2 (3×50 mL)
  5. dry with materialdried over Na2SO4
  6. filtrationAfter filtration the solvent
  7. customwas removed by evaporation under vacuum
  8. customthe residue was purified on silica gel column (1:10 EtOAc/hexanes)

Sources & evidence

ORD record
ord-3dd3ab2761bb47418ff14163eb6b8fbd
Source dataset
uspto-grants-2009_06
Patent number
US07550484B2

Reaction notes

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