Dimethylformamide → 2,2-Difluoro-5-formylbenzodioxole

HRID 249707Notes

Reaction equation

HRID 249707 reaction equation
Br[C:2]1[CH:12]=[CH:11][C:5]2[O:6][C:7]([F:10])([F:9])[O:8][C:4]=2[CH:3]=1.[Li]CCCC.CN([CH:21]=[O:22])C>C1COCC1>[F:9][C:7]1([F:10])[O:6][C:5]2[CH:11]=[CH:12][C:2]([CH:21]=[O:22])=[CH:3][C:4]=2[O:8]1

Participants

5

Reactant 3

HCID 6228DimethylformamideHCID 27362715-Bromo-2,2-difluoro-1,3-benzodioxoleHCID 178418339Butyllithium

Product 1

HCID 27369732,2-Difluoro-5-formylbenzodioxole

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

A solution of 127 mmol of 5-bromo-2,2-difluorobenzo[d][1,3]dioxole in 200 mL of THF is cooled under argon in a CO2/acetone bath and treated with 1.05 equivalents of n-BuLi in THF. The mixture is stirred for about 10 min in the cold, then treated with 1.2 equivalents of DMF. The mixture is stirred for 30 min in the cold, then the cold bath is removed and the reaction is stirred for 1.5 h at ambient temperature and then quenched with 150 mL of saturated ammonium chloride solution. The organic layer is separated and the aqueous layer is washed 2× with ether. The combined organics are washed with brine, dried over MgSO4 and concentrated in vacuo. Silica gel chromatography (EtOAc/hexanes eluant) yields the title compound.

Workup

  1. stirringThe mixture is stirred for 30 min in the cold, then the cold bath
  2. customis removed
  3. stirringthe reaction is stirred for 1.5 h at ambient temperature
  4. customquenched with 150 mL of saturated ammonium chloride solution
  5. customThe organic layer is separated
  6. washthe aqueous layer is washed 2× with ether
  7. washThe combined organics are washed with brine
  8. dry with materialdried over MgSO4
  9. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-bfddd5d884504ad18c9aa86cd344e352
Source dataset
uspto-grants-2011_01
Patent number
US07863274B2

Reaction notes

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