Who is Who in the Carbene Chemistry of N‐Sulfonyl Hydrazones

Comprehensive Summary Over the past few decades, N‐sulfonyl hydrazones have been recognized as alternative precursors for hazardous diazo compounds in organic synthesis, allowing for diverse innovative and original chemical transformations that were otherwise difficult to achieve. This critical review summarizes the major advancements in the carbene chemistry of N‐sulfonyl hydrazones. The contents of this review are organized based on research conducted by leading scientists who have made significant contributions to this field. The individual carbene transfer reactions and their mechanisms, as well as the potential applications in the synthesis of natural products and complex bioactive molecules, are thoroughly discussed. This review examines key scientists who have made significant contributions to the emerging carbene chemistry of N‐sulfonyl hydrazones. Current challenges in this field are summarized, and a brief outlook for future development is prospected.