Diethyl Oxalate → 1,4-Dimethylpiperazine-2,3-dione

Participants

Reaction Steps

To a stirred solution of N,N′-dimethylethylenediamine (25.0 g, 0.28 mol) in 150 mL of dry diethyl ether was added diethyl oxalate (38.5 mL, 0.28 mol) in one portion. After a few minutes white crystals started to precipitate. The reaction mixture was stirred at room temperature overnight. The product was filtered and washed with dry diethyl ether. The product was dried under vacuum at 47° C. overnight to give colorless crystals (38.64 g, 96%). 1H NMR (200 MHz, CDCl3, δ): 3.50 (s, 4H), 2.99 (s, 6H). 13C{1H} NMR (200 MHz, CDCl3, δ): 157.35, 45.91, 34.74.

Provenance & Evidence