Popis: |
A convenient C(sp3)–C(sp3) oxidative dehydrogenative coupling reaction of 1,4-benzoxazin-2-ones with malonate esters was developed under mild conditions to obtain the respective ester malonates in high yields. Reactions take place in [omim]FeCl4, acting as both the solvent and the catalyst. Under [omim]Cl/FeCl3-DDQ conditions, derivatives of 1 coupled with malonate 2 to give the target molecules within 1–2 h time periods. The ionic liquid was recovered and reused in the next reactions without losing its efficiency. |