反应详情

温度

110 °C

25.0 g of global 2,5-piperazinedione 1 [2,5-piperazinedione (Aldrich G640-6), 25.0 g, 0.218 mol] in 100 mL of acetic anhydride (Ac2O) was mixed with sodium acetate (NaOAc) (17.96 g, 0.0218 mol). The mixture was heated at 110° C. for 8 h using a double coiled condenser under an Ar atmosphere. After Ac2O was removed by evaporation, the residue was dissolved in AcOEt, washed with 10% citric acid, 10% NaHCO3 and saturated NaCl (three times each), dried over Na2SO4, and concentrated in vacuo. The residue was triturated with ether to form a solid. This solid was recrystallized from EtOAc with ether-hexane to afford 26.4 g (61%) of N,N′-diacetyl-2,5-piperazinedione 1.

1. customAfter Ac2O was removed by evaporation
2. dissolutionthe residue was dissolved in AcOEt
3. washwashed with 10% citric acid, 10% NaHCO3 and saturated NaCl (three times each),
4. dry with materialdried over Na2SO4
5. concentrationconcentrated in vacuo
6. customThe residue was triturated with ether
7. customto form a solid
8. customThis solid was recrystallized from EtOAc with ether-hexane