Dimethylformamide → HCID 86587404, compound

HRID 1830564Notes

Reaction equation

HRID 1830564 reaction equation
Br[C:2]1[C:6]2[CH:7]=[CH:8][CH:9]=[CH:10][C:5]=2[O:4][C:3]=1[CH:11]1[O:15][CH2:14][CH2:13][O:12]1.CN([CH:19]=[O:20])C.O.O.C(O)(=O)C(O)=O>CCOCC.O.CCOC(C)=O>[O:12]1[CH2:13][CH2:14][O:15][CH:11]1[C:3]1[O:4][C:5]2[CH:10]=[CH:9][CH:8]=[CH:7][C:6]=2[C:2]=1[CH:19]=[O:20]

Participants

7

Reactant 3

HCID 6228DimethylformamideHCID 61373Oxalic acid dihydrateHCID 12337274HCID 12337274, compound

Product 1

HCID 86587404HCID 86587404, compoundYield 72%

Reagents, catalysts & solvents 3

HCID 962WaterSolvent2×HCID 3283Diethyl EtherSolvent2×HCID 8857Ethyl AcetateSolvent

Conditions

Temperature
-78 °C

Procedure

3-Bromo-2-(1,3-dioxolan-2-yl)-1-benzofuran (6.6 g 24.5 mmol) is dissolved in Et2O (100 ml) in a 3-neck, flame-dried, round-bottom flask under nitrogen and cooled to −78° C. tert-butylithium (31.7 ml, 53.9 mmol) is added dropwise, and the chilled solution is stirred 1 h. DMF (2.18 ml, 28.2 mmol) is dissolved in Et2O (25 ml) and also added dropwise, and the mixture is stirred at −78° C. for another 7 h. The reaction is warmed to rt, whereby oxalic acid dihydrate (6.18 g, 49.0 mmol) and water (25 ml) are added. The reaction continued stirring at rt overnight and is then diluted with water (125 ml) and EtOAc (175 ml). The layers are allowed to separate, and the aqueous is extracted with EtOAc (1×100 ml). The organics are combined, dried over sodium sulfate, filtered, and concentrated to a brown oil. The crude material is chromatographed over 350 g slurry-packed silica, eluting with 30% ethyl acetate/hexane. The appropriate fractions are combined and concentrated to afford 3.84 g (72%) of 2-(1,3-dioxolan-2-yl)-1-benzofuran-3-carbaldehyde as a yellow/orange oil. MS (EI) m/z: 218 (M+).

Workup

  1. customflame-dried
  2. additionis added dropwise
  3. additionalso added dropwise
  4. stirringthe mixture is stirred at −78° C. for another 7 h
  5. temperatureThe reaction is warmed to rt
  6. stirringThe reaction continued stirring at rt overnight
  7. customto separate
  8. extractionthe aqueous is extracted with EtOAc (1×100 ml)
  9. dry with materialdried over sodium sulfate
  10. filtrationfiltered
  11. concentrationconcentrated to a brown oil
  12. customThe crude material is chromatographed over 350 g slurry-packed silica
  13. washeluting with 30% ethyl acetate/hexane
  14. concentrationconcentrated

Sources & evidence

ORD record
ord-bc43d9e39ebc403683ecd96529c02875
Source dataset
uspto-grants-2006_06
Patent number
US07067515B2

Reaction notes

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