Diethyl Oxalate → HCID 57435092, compound

HRID 1724758Notes

Reaction equation

HRID 1724758 reaction equation
[H-].[Na+].[CH3:3][C:4]([CH3:11])=[CH:5][CH2:6][CH2:7][C:8](=[O:10])[CH3:9].[CH2:12]([O:14][C:15](=[O:21])[C:16](OCC)=[O:17])[CH3:13].CC[O-].[Na+]>CCO>[CH2:12]([O:14][C:15](=[O:21])[C:16](=[O:17])[CH2:9][C:8](=[O:10])[CH2:7][CH2:6][CH:5]=[C:4]([CH3:11])[CH3:3])[CH3:13]

Participants

6

Reactant 4

HCID 7268Diethyl OxalateHCID 98626-Methyl-5-hepten-2-oneHCID 24758Sodium hydrideHCID 2723922Sodium ethoxide

Product 1

HCID 57435092HCID 57435092, compoundYield 43.9%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

Sodium hydride (0.465 g, 19.4 mmol) was added slowly to a NaCl ice bath containing EtOH (5.88 mL, 3.3 M) stirring under N2. 6-Methylhept-5-en-2-one (2.4412 g, 19.3 mmol) and diethyloxalate (2.63 mL, 19.4 mmol) were mixed together, and then added to the chilled NaOEt solution. After stirring for 15 minutes, the reaction was warmed to room temperature and stirred for 6 hours, at which point the reaction was judged complete by TLC. 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, and purified by silica gel chromatography (Combiflash column, 70:30:3 Hexanes: CH2Cl2:2N NH3 in EtOH): Only pure fractions were combined and concentrated to obtain 1.9190 g (43.8%) of 49. 1H (CDCl3, 400 MHz): δ 14.44 (1H, broad s), 6.34 (1H, s), 5.06 (1H, t, J=7.3 Hz, 4.33 (2H, q, J=7.1 Hz), 2.49 (2H, t, J=7.3 Hz), 2.31 (2H, q, J=7.3 Hz), 1.66 (3H, s), 1.60 (3H, s), 1.35 (3H, t, J=7.1 Hz) ppm. 13C (CDCl3, 100 MHz): δ 202.83, 166.39, 162.08, 133.42, 121.90, 101.64, 62.40, 40.92, 25.59, 23.34, 17.61, 13.96 ppm. DEPT (CDCl3, 100 MHz): CH3 carbons: 25.59, 17.62, 13.97; CH2 carbons: 62.40, 40.92, 23.34; CH carbons: 121.90, 101.64 ppm. HPLC: 11.007 min.

Workup

  1. stirringAfter stirring for 15 minutes
  2. stirringstirred for 6 hours, at which
  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. custompurified by silica gel chromatography (Combiflash column, 70:30:3 Hexanes: CH2Cl2:2N NH3 in EtOH)
  10. concentrationconcentrated

Sources & evidence

ORD record
ord-adc2e810d6f5422a925f2077bd6310ee
Source dataset
uspto-grants-2009_02
Patent number
US07488747B2

Reaction notes

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