A [3 + 2] Annulation for the Synthesis of Pyrazolyl Vinyl Sulfonyl Fluorides: A Class of Important Pharmacophore

The accelerating convergence of Sulfur Fluoride Exchange (SuFEx) click chemistry and heterocyclic scaffold diversification has driven unprecedented advances in covalent inhibitor design while offering versatile platforms for generating potential bioactive entities. Herein, we report the use of a stabilized diazo group as a reactive motif, which undergoes a 1,3-dipolar cycloaddition with 1-bromobut-3-ene-1,3-disulfonyl difluoride (BEDF), a versatile connective hub, under mild conditions to afford target compounds with controlled regioselectivity and stereoselectivity. This methodology establishes a robust and efficient route to diverse sulfonyl fluoride building blocks that hold great potential for the development of bioactive molecules.