Diethyl Oxalate → 7-Methyl-2,4-dioxooctanoic acid ethyl ester

HRID 1724755Notes

Reaction equation

HRID 1724755 reaction equation
[CH3:1][CH:2]([CH3:8])[CH2:3][CH2:4][C:5](=[O:7])[CH3:6].[CH2:9]([O:11][C:12](=[O:18])[C:13](OCC)=[O:14])[CH3:10].CC[O-].[Na+]>>[CH2:9]([O:11][C:12](=[O:18])[C:13](=[O:14])[CH2:6][C:5](=[O:7])[CH2:4][CH2:3][CH:2]([CH3:8])[CH3:1])[CH3:10]

Participants

4

Reactant 3

HCID 7268Diethyl OxalateHCID 80345-Methyl-2-hexanoneHCID 2723922Sodium ethoxide

Product 1

HCID 574350907-Methyl-2,4-dioxooctanoic acid ethyl esterYield 70.4%

Procedure

5-methyl-2-hexanone (5.0084 g, 43.9 mmol) and diethyloxalate (5.95 mL, 43.8 mmol) were mixed together, and then added to a solution of NaOEt (˜3 M, 14.6 mL) stirring in an ice bath under N2. After stirring for 15 minutes, the reaction was warmed to room temperature and stirred overnight. The reaction was quenched at 0° C. with 1N HCl and extracted 2× with CH2Cl2. The combined organics were washed with H2O, dried with Na2SO4, filtered, and concentrated to yield crude 46. The crude material was purified with 1:1 Hexanes: CH2Cl2 to obtain 6.6035 g (70.3%) of 46. 1H (CDCl3, 400 MHz): δ 6.28 (1H, s), 4.25 (2H, q, J=7.0 Hz), 2.40 (2H, t, 7.6 Hz), 1.54-1.41 (3H, m), 1.27 (3H, t, J=7.3 Hz), 0.82 (6H, d, J=6.3 Hz) ppm. 13C (CDCl3, 100 MHz): δ 203.40, 166.27, 161.85, 101.37, 62.15, 38.74, 33.39, 27.46, 21.99, 13.77 ppm. DEPT (CDCl3, 100 MHz): CH3 carbons: 21.99, 13.77; CH2 carbons: 62.15, 38.74, 33.39; CH carbons: 101.37, 27.46 ppm. HPLC: 11.038min.

Workup

  1. stirringAfter stirring for 15 minutes
  2. stirringstirred overnight
  3. customThe reaction was quenched at 0° C. with 1N HCl
  4. extractionextracted 2× with CH2Cl2
  5. washThe combined organics were washed with H2O
  6. dry with materialdried with Na2SO4
  7. filtrationfiltered
  8. concentrationconcentrated
  9. customto yield crude 46
  10. customThe crude material was purified with 1:1 Hexanes

Sources & evidence

ORD record
ord-5ab364365ed5432cb19059587e099df5
Source dataset
uspto-grants-2009_02
Patent number
US07488747B2

Reaction notes

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