Dimethylformamide → 2,3-Dihydro-1-benzofuran-7-carbaldehyde

HRID 1107866Notes

Reaction equation

HRID 1107866 reaction equation
C([Li])CCC.CN(C)CCN(C)C.[O:14]1[C:18]2[CH:19]=[CH:20][CH:21]=[CH:22][C:17]=2[CH2:16][CH2:15]1.CN(C)[CH:25]=[O:26]>CCCCCC.O>[CH:25]([C:19]1[C:18]2[O:14][CH2:15][CH2:16][C:17]=2[CH:22]=[CH:21][CH:20]=1)=[O:26]

Participants

7

Reactant 4

HCID 6228DimethylformamideHCID 8037N,N,N',N'-TetramethylethylenediamineHCID 10329DihydrobenzofuranHCID 178418339Butyllithium

Product 1

HCID 27950182,3-Dihydro-1-benzofuran-7-carbaldehydeYield 35%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8058HexaneSolvent

Procedure

108 ml of an n-butyllithium solution (2.1M) in hexane and 26.7 g (230 mmol) of tetramethylethylenediamine (TMEDA) are introduced into a 1 liter round-bottomed flask. The mixture is stirred at room temperature for 15 minutes and 23 g (190 mmol) of 2,3-dihydrobenzofuran are added. The mixture is stirred for 4 hours at 35° C., cooled to -78° C. and 13.9 g (190 mmol) of dimethylformamide are added. The temperature is allowed to return to 20° C., 500 ml of water are added and extraction is carried out with ethyl acetate (3×200 ml). The organic phases are combined, dried and concentrated under vacuum. The residue is purified by silica flash chromatography (elution: 5% ethyl acetate in petroleum ether). 9.85 g (Yield: 35%) of 7-formyl-2,3-dihydrobenzofuran are obtained--M.p.: 55° C.

Workup

  1. stirringThe mixture is stirred for 4 hours at 35° C.
  2. temperaturecooled to -78° C.
  3. customto return to 20° C.
  4. extractionextraction
  5. customdried
  6. concentrationconcentrated under vacuum
  7. customThe residue is purified by silica flash chromatography (elution: 5% ethyl acetate in petroleum ether)

Sources & evidence

ORD record
ord-b3d7afba98e9461687c4daf3ee2eb927
Source dataset
uspto-grants-2000_05
Patent number
US06063810

Reaction notes

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