Oxalyl chloride → NSC 25351

Participants

Reaction Conditions

Reaction Steps

As shown in FIG. 2A, diacid 2 (8.76 g, 29.2 mmol) was suspended in dry dichloromethane (ca. 300 mL) in a dry, septum-capped round-bottom flask, to which was added a few drops of dry dimethylformamide. The mixture was cooled to 0° C. in an ice-water bath and the flask was connected to a oil-bubbler with flexible plastic tubing. Oxalyl chloride (3.9 g, 30.7 mmol) was added dropwise with a syringe as the suspension was stirred. Within few minutes, gas was released through the oil bubbler as the reaction began. The reaction mixture was adequately cooled prior to the addition of oxalyl chloride to avoid a violent release of gas. The reaction mixture was allowed to warm to room temperature as it was stirred overnight (ca. 16 h), during which the reaction mixture became homogeneous. The solvent was evaporated under vacuum and the resulting crude product was recrystallized from toluene to give the title compound as pale beige crystals (7.41 g, 90%). 1H NMR (500 MHz, CDCl3): 7.45 (4H, dd, J=5.2 and 3.2 Hz), 7.09 (4H, dd, J=5.0 and 3.5 Hz), 5.55 (2H, s).

Provenance & Evidence