Benzaldehyde → (Z)-1-Acetyl-3-benzylidenepiperazine-2,5-dione

Participants

Reaction Steps

To a solution of benzaldehyde 4 (0.54 g, 5.05. mmol) in DMF (5 mL) was added compound 1 (2.0 g, 10.1 mmol) and the solution was repeatedly evacuated in a short time to remove oxygen and flushed with Ar, followed by the addition of Cs2CO3 (1.65 g, 5.05 mmol) and the evacuation-flushing process was repeated again. The resultant mixture was stirred for 3.5 h at room temperature. After the solvent was removed by evaporation, the residue was dissolved in the mixture of EtOAc and 10% Na2CO3, and the organic phase was washed with 10% Na2CO3 again and saturated NaCl for three times, dried over Na2SO4 and concentrated in vacuo. The residual solid was recrystalized from MeOH-ether to obtain a off-white solid of 17; yield 1.95 g (79%).

Provenance & Evidence