Diethyl Oxalate → HCID 57435094, compound

Participants

Reaction Steps

Sodium hydride (0.6447 g, 25.52 mmol) was added slowly to a NaCl ice bath containing EtOH (10 mL, 2.6 M) stirring under N2. 4-(2,2,6-trimethylcyclohexyl)-butan-2-one (5.0072 g, 25.50 mmol) and diethyloxalate (3.7241 g, 25.48 mmol) were mixed together, and then added to the chilled NaOEt solution. After stirring for 5 minutes, the reaction was warmed to room temperature. The reaction quickly solidified. An additional 10 mL EtOH was added, and the reaction was allowed to stand for another 3 h. 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, concentrated, and purified by silica gel chromatography (Combiflash column, 1:1 Hexanes:CH2Cl2): Only pure fractions were combined and concentrated to obtain 52. 1H (CDCl3, 400 MHz): δ 14.51 (1H, broad s), 6.34 (1H, s), 4.34 (2H, q, J=7.1 Hz), 2.44 (2H, t, J=8.3 Hz), 1.96-1.84 (1H, m), 1.68-1.22 (m), 1.36 (3H, t, J=7.1 Hz), 1.18-0.98 (m), 0.94 (3H, s), 0.87 (3H, s), 0.85 (3H, d, J=7.3 Hz) ppm. Partial 13C (CDCl3, 100 MHz): δ 203.45, 167.17, 162.40, 101.80, 62.71, 49.28, 42.60, 30.46, 20.86, 14.27 ppm. Partial DEPT (CDCl3, 100 MHz): CH3 carbons: 14.27; CH2 carbons: 62.71; CH carbons: 101.80 ppm. HPLC: 12.576 min.

Provenance & Evidence