Tosylimidazole-mediated one-pot synthesis of 2-azetidinones

Cyclocondensation of Schiff bases and substituted acetic acid with tosylimidazole afforded 2-azetidinones in good to excellent yields. This reaction works reliably well for monocyclic and spirocyclic 2-azetidinones. This reaction is green and efficient and the products can be purified by simple crystallisation.