Diethyl Oxalate → 6-(4-Methoxyphenyl)-2,4-dioxohexanoic acid ethyl ester

Reaction equation

[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6]([CH2:9][CH2:10][C:11](=[O:13])[CH3:12])=[CH:5][CH:4]=1.[CH2:14]([O:16][C:17](=[O:23])[C:18](OCC)=[O:19])[CH3:15].CC[O-].[Na+]>CCO>[CH2:14]([O:16][C:17](=[O:23])[C:18](=[O:19])[CH2:12][C:11](=[O:13])[CH2:10][CH2:9][C:6]1[CH:7]=[CH:8][C:3]([O:2][CH3:1])=[CH:4][CH:5]=1)[CH3:15]

Participants

Procedure

4-(4-methoxyphenyl)-2-butanone (14.9908 g, 84.2 mmol) and diethyloxalate (12.3434 g, 84.2 mmol) were mixed together, and then added to a solution of NaOEt (3 M, 28.1 mL) stirring in an ice bath under N2. After stirring for 15 minutes, the reaction was warmed to room temperature and stirred. After 10 min, the reaction completely solidified. An additional 100 mL EtOH was added, the reaction was placed on mechanical shaker 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 22. The crude material was purified with 1:1 Hexanes:CH2Cl2 to obtain 22. 1H (CDCl3, 400 MHz): δ 14.39 (1H, broad s), 7.10 (2H, d, J=7.1 Hz), 6.82 (2H, d, J=6.3 Hz), 6.34 (1H, s), 4.33 (2H, q, J=7.1 Hz), 3.77 (3H, s), 2.91 (2H, t, J=7.3 Hz), 2.78 (2H, t, J=7.3 Hz), 1.36 (3H, t, J=7.1 Hz) ppm. 13C (CDCl3, 100 MHz): δ 202.53, 166.46, 162.29, 158.36, 132.36, 129.44, 114.20, 102.11, 62.75, 55.47, 43.02, 29.94, 14.27 ppm. DEPT (CDCl3, 100 MHz): CH3 carbons: 55.47, 14.27; CH2 carbons: 62.75, 43.02, 29.94; CH carbons: 129.44, 114.20, 102.11 ppm. HPLC: 10.12 min. (Starting material: HPLC: 9.10 min.)