Oxazinoazaarenes as Versatile Intermediates for Regioselective Late-Stage C-H-Functionalization and Skeletal Editing of Pyridines, Isoquinolines and Quinolines.

Azaarenes, particularly pyridines, represent some of the most important structural and functional motifs across various fields. Consequently, late-stage C-H bond functionalization and skeletal editing of azaarenes hold significant value, particularly for accelerating structure-activity relationship studies. Dearomatized intermediates derived from such azaarenes offer an innovative strategy for selectively modifying these valuable cores. Among them, oxazinoazaarenes are a practical and scalable platform for regioselective meta- and para-C-H functionalization and skeletal editing of the azaarene moiety. This short review highlights the advancements in oxazinoazaarene-based pyridine modification methods achieved by our group and others.