1,2-Dibromoethane → tert-Butyl 1-acetylcyclopropanecarboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of tert-butyl acetoacetate (497 mL, 3.00 mol), 1,2-dibromoethane (310 mL, 3.60 mmol), potassium carbonate (1.106 k g, 8.00 mmol), and dimethylformamide (2.0 L) was stirred in a water bath at 30° C. for 1.5 hours, in a water bath at 60° C. for 3.5 hours, and in a water bath at 30° C. for 4 days. The reaction mixture was separated by filtration through celite, and the residue on the celite was washed with diethylether (3.5 L). The filtrate and the diethylether used for the washing were combined and added to water (2 L), and the organic layer was separated. The aqueous layer was extracted with diethylether (2 L), and water (1 L) was added to the resulting aqueous layer, and further extraction was conducted by adding diethylether (2 L). All organic layers were combined, and washed with 10% aqueous solution of citric acid (2 L), water (2 L×3), and saturated aqueous solution of sodium chloride (2 L×3), and dried by adding anhydrous sodium sulfate. After removing the dessicating agent by filtration, the solvent was removed by distillation under reduced pressure, and the residue was distilled under reduced pressure to obtain 371.8 g of the target compound (10 mmHg, distillation fraction of 72 to 78° C., 2.02 mol, 67%) as a colorless transparent oil.

Provenance & Evidence