Diethyl Oxalate → Ethyl 2-methoxybenzoylformate

HRID 1593397Notes

Reaction equation

HRID 1593397 reaction equation
Br[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=1[O:8][CH3:9].C([Li])CCC.[C:15](OCC)(=[O:21])[C:16]([O:18][CH2:19][CH3:20])=[O:17].[NH4+].[Cl-]>CCOCC.CCCCC>[CH3:9][O:8][C:3]1[CH:4]=[CH:5][CH:6]=[CH:7][C:2]=1[C:15](=[O:21])[C:16]([O:18][CH2:19][CH3:20])=[O:17]

Participants

7

Reactant 4

HCID 7268Diethyl OxalateHCID 113582-BromoanisoleHCID 25517Ammonium ChlorideHCID 178418339Butyllithium

Product 1

HCID 15579652Ethyl 2-methoxybenzoylformate

Reagents, catalysts & solvents 2

HCID 3283Diethyl EtherSolventHCID 8003PentaneSolvent

Procedure

A solution of 27 g of 1-bromo-2-methoxybenzene in 270 ml of ether is cooled to −70° C., under an argon atmosphere, 90 ml of a 1.6 M solution of n-butyllithium in pentane are added drop wise and the mixture is then stirred for 45 minutes. 78 ml of diethyl oxalate are added rapidly and the mixture is stirred while allowing the temperature to return to RT. After stirring for 1 hour at RT, saturated NH4Cl solution is added to the reaction mixture, the phases are separated by settling, the aqueous phase is extracted with ether, the combined organic phases are washed with water, with saturated NaCl solution and dried over Na2SO4, and the solvents are evaporated off under vacuum. The excess diethyl oxalate is removed by distillation under vacuum (b.p.=87° C. at 2000 Pa). The resulting product is chromatographed on silica gel eluting with a DCM/hexane mixture (50/50; v/v) and then with DCM. The product obtained is purified by distillation under vacuum. 13 g of the expected product are obtained; b.p.=110° C. at 3 Pa.

Workup

  1. stirringthe mixture is stirred
  2. customto return to RT
  3. stirringAfter stirring for 1 hour at RT
  4. customthe phases are separated
  5. extractionthe aqueous phase is extracted with ether
  6. washthe combined organic phases are washed with water, with saturated NaCl solution
  7. dry with materialdried over Na2SO4
  8. customthe solvents are evaporated off under vacuum
  9. customThe excess diethyl oxalate is removed by distillation under vacuum (b.p.=87° C. at 2000 Pa)
  10. customThe resulting product is chromatographed on silica gel eluting with a DCM/hexane mixture (50/50; v/v)
  11. customThe product obtained
  12. distillationis purified by distillation under vacuum

Sources & evidence

ORD record
ord-4bc41e922af743d9a4a0c2c2374d2322
Source dataset
uspto-grants-2007_11
Patent number
US07297692B2

Reaction notes

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