Application of DNA‐Conjugated Aryl Diazonium Intermediates in DNA‐Encoded Libraries

Aryl diazonium intermediates have emerged as highly versatile intermediates in modern organic synthesis and chemical biology, demonstrating remarkable reactivity under mild reaction conditions. Their significance has extended to DNA‐encoded libraries (DELs), where they serve as valuable alternatives to traditional aryl halide‐based cross‐coupling reactions. Aryl diazonium intermediates as N2‐annulation synthons can efficiently transform into benzotriazinone core on DNA besides C–C coupling. This concept paper illuminates recent advances in this field, emphasizing their applications and potential across various facets of DELs, off‐DNA chemistry, DELs selection, and DNA‐based probes. It is anticipated that these developments will propel the broader utilization of DNA‐conjugated aryl diazonium salt intermediates in DELs, protein labeling, hit discovery, and other interdisciplinary fields.