N‐Heteroaromatic Fluoroalkylation through Ligand Coupling Reaction of Sulfones

Abstract Ligand coupling on hypervalent main group elements has emerged as a pivotal methodology for the synthesis of functionalized N ‐heteroaromatic compounds in recent years due to the avoidance of transition metals and the mildness of the reaction conditions. In this direction, the reaction of N‐ heteroaryl sulfur(IV) and N‐ heteroaryl phosphorus(V) compounds has been well studied. However, the ligand coupling of sulfur(VI) is still underdeveloped and the reaction of alkyl N‐ heteroarylsulfones is still elusive, which does not match the high status of sulfones as the chemical chameleons in organic synthesis. Here we present a ligand coupling‐enabled formal SO 2 extrusion of fluoroalkyl 2‐azaheteroarylsulfones under the promotion of Grignard reagents, which not only enriches the chemistry of sulfones, but also provides a novel and practical synthetic tool towards N‐ heteroaromatic fluoroalkylation.