Bromide ion → 1,3-Dichloro-5-ethynylbenzene

HRID 1865417Notes

Reaction equation

HRID 1865417 reaction equation
[Br-].[C:2]([Mg]Br)#[CH:3].[Cl:6][C:7]1[CH:8]=[C:9](I)[CH:10]=[C:11]([Cl:13])[CH:12]=1>C1COCC1.[Cl-].[Na+].O.[Zn]>[Cl:6][C:7]1[CH:8]=[C:9]([C:2]#[CH:3])[CH:10]=[C:11]([Cl:13])[CH:12]=1

Participants

7

Reactant 3

HCID 259Bromide ionHCID 764241,3-Dichloro-5-iodobenzeneHCID 178418486HCID 178418486, compound

Product 1

HCID 138235471,3-Dichloro-5-ethynylbenzene

Reagents, catalysts & solvents 3

HCID 23994ZincCatalystHCID 8028TetrahydrofuranSolventHCID 57417360Sodium chloride; waterSolvent

Procedure

To a solution of zinc, bromide (5.0 g, 22.2 mmol) in anhydrous THF (100 mL) at room temperature under a nitrogen atmosphere was added a solution of ethynyl magnesium bromide (0.5 M in THF, 44.4 mL, 44.4 mmol). After 5 minutes 3,5-dichloro-iodobenzene was added (4.03 g, 14.8 mmol) followed by tetrakis-triphenyl phosphine palladium (0) (855 mg, 0.74 mmol). The reaction was stirred at room temperature for 18 hours. The reaction mixture was poured into brine and extracted with ether (4×100 mL). The ether layer was washed with brine, dried over anhydrous MgSO4, filtered and concentrated in vacuo. The residue was purified by flash chromatography with 100% hexanes to give the title compound as a yellow solid. 1H NMR (CDCl3, 500 MHz): 7.4 (d, J=1.6 Hz, 2H), 7.3 (d, J=1.6 Hz, 1H), 3.19 (s, 1H).

Workup

  1. extractionextracted with ether (4×100 mL)
  2. washThe ether layer was washed with brine
  3. dry with materialdried over anhydrous MgSO4
  4. filtrationfiltered
  5. concentrationconcentrated in vacuo
  6. customThe residue was purified by flash chromatography with 100% hexanes

Sources & evidence

ORD record
ord-fba57012f6194f30a15da46caf9e9929
Source dataset
uspto-grants-2009_12
Patent number
US07625938B2

Reaction notes

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