“…Transforming parent molecular frameworks into structurally related compounds through the insertion of single atoms has gained increased attention over the last decades, further expanding the synthetically accessible chemical space. − Through the insertion of heteroatoms such as oxygen − or nitrogen − into abundant frameworks, rapid access to a diverse array of shape-similar targets with modulated pharmacokinetic properties is possible. Additionally, applying these strategies to diversify target structures at a late stage obviates time-consuming de novo syntheses and directly affords biologically interesting heterocycles expanding available medicinal chemistry libraries. , Recently, various methods were developed to interconvert widely encountered scaffolds such as indoles and pyrroles into the corresponding carbon-atom extended frameworks, including quinolines and pyridines. − Strategies to afford the corresponding N , N -heterocycles were also disclosed, however, these either depend on harsh reaction conditions and present a limited scope or rely on the use of protecting group strategies that require a separate prefunctionalization step (Figure a). , In addition, the strategically related development of a nitrogen atom insertion into pyrroles to access the corresponding pyrimidine motifs is underdeveloped and was showcased for only two selected examples, 2,3,4,5-tetraphenyl-1 H -pyrrole (Figure b) , and ethyl 4-(4-methoxyphenyl)-2,5-dimethyl-1 H -pyrrole-3-carboxylate …”