KO<i>t</i>Bu-Promoted [4+2] Annulation-Dehydration\nCascade Enabling the Construction of Diverse 2‑Pyridone-Fused\nUracils

A KO<i>t</i>Bu-promoted [4+2] annulation-dehydration\ncascade reaction has been developed, enabling the efficient synthesis\nof diverse 2-pyridone-fused uracils through a vinylogous enolization\nstrategy involving <i>o</i>-quinodimethane (<i>o</i>QDM) dienolate intermediates. This method provides a simple yet robust\napproach for constructing structurally interesting fused <i>N</i>-heterocycles that incorporate two privileged scaffolds, both of\nwhich are widely recognized in drug discovery. Consequently, these\ncompounds hold significant potential for biological and pharmacological\napplications. Moreover, further transformations of the products obtained\nfrom this process allow access to highly functionalized and structurally\ndiverse uracil derivatives, expanding the scope of accessible chemical\ndiversity.