Heteroaryl groups are functional groups in organic molecules that contain a heteroaromatic ring with at least one heteroatom, such as nitrogen, oxygen, and sulphur. They are naturally abundant and widely utilized in functionalized organic molecules. For example, pyridine, one of the most prevalent nitrogen-containing heteroarenes, is present in 54 small molecule drugs approved by the FDA between 2013 and 2023. Heteroaryls are also common structural motifs in both coupling partners and catalysts in transition metal catalysis and organocatalysis. The prevalence of heteroaromatic compounds is attributed to several factors. First, different heteroarene cores have distinct electronic and steric properties that effectively alter the target compound's chemical reactivity and biological function. One area where these properties have been leveraged is in the design of covalent modifier drugs with warhead reactivity modulated by heteroaryl groups; examples of this include FDA-approved drugs afatinib and selinexor, as well as other covalent modifiers such as roblitinib, nitrofuran derivative C-176, and TC9-305 (Fig. ). Second, heteroarene cores could be further functionalized with electron-donating or electron-withdrawing substituents at different sites, leading to a large number of regioisomers with a substantially expanded property space of heteroaromatic compounds. Third, structurally diverse functionalized heteroarenes could be synthesized from readily available starting materials via a number of established synthetic methods, including recently developed strategies via site-selective functionalization and skeletal editing .