The synthesis of multi-substituted pyrrolidinones via a direct [3 + 2] cycloaddition of azaoxyallyl cations with aromatic ethylenes.

A novel [3 + 2] cycloaddition reaction of azaoxyallyl cations and aromatic ethylenes has been developed to afford multi-substituted pyrrolidinones in moderate to good yields. This method not only further expands the synthetic utility of α-halo hydroxamates, but also provides an alternative method for the synthesis of bioactive molecules containing pyrrolidinones.