Diethyl Oxalate → Ethyl oxo(2-oxocycloheptyl)acetate
Reaction equation
[C:1]1(=[O:8])[CH2:7][CH2:6][CH2:5][CH2:4][CH2:3][CH2:2]1.[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])[CH:2]1[CH2:3][CH2:4][CH2:5][CH2:6][CH2:7][C:1]1=[O:8])[CH3:10]Participants
Procedure
Cycloheptanone (1.9998 g, 17.8 mmol) and diethyloxalate (2.42 mL, 17.8 mmol) were mixed together, and then added to a solution of NaOEt (˜3 M, 5.94 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 13. The crude material was purified with 1:1 Hexanes:CH2Cl2 to obtain 1.9775 g (52.3%) of 13. Note: The product was still not completely pure at this point, but was carried on to the next step. 1H (CDCl3, 400 MHz): δ 4.31 (2H, q, J=7.3 Hz), 2.66-2.58 (2H, m), 2.48-2.43 (2H, m), 1.77-1.59 (6H, m), 1.34 (3H, t, J=7.3H) ppm.
Workup
- stirringAfter stirring for 15 minutes
- stirringstirred overnight
- customThe reaction was quenched at 0° C. with 1N HCl
- extractionextracted 2× with CH2Cl2
- washThe combined organics were washed with H2O
- dry with materialdried with Na2SO4
- filtrationfiltered
- concentrationconcentrated
- customto yield crude 13
- customThe crude material was purified with 1:1 Hexanes
Sources & evidence
- ORD record
- ord-960d352f4f25498dabe777ad059c4715
- Source dataset
- uspto-grants-2011_02
- Patent number
- US07893098B2
Reaction notes
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