Strain‐Driven Dyotropic Rearrangement: A Unified Ring‐Expansion Approach to α‐Methylene‐γ‐butyrolactones

Fehér P, Stirling A, Czégény Z, Bényei A, Novák Z. Synthesis of Hydrofluoroolefin‐Based Iodonium Reagent via Dyotropic Rearrangement and Its Utilization in Fluoroalkylation

[1,2]‐shift of atoms in alkyl fragments belongs to the class of dyotropic rearrangements. Various atoms, including halogens can be involved in the migration, however participation of iodine is unprecedented. Herein, we report our experimental and DFT studies on the oxidation triggered dyotropic rearrangement of iodo and chloro functions via butterfly‐type transition state to demonstrate the migrating ability of λ³‐iodane centre. With the exploitation of dyotropic rearrangement we designed and synthesized a novel fluoroalkyl iodonium reagent from industrial feedstock gas HFO‐1234yf. We demonstrated that the hypervalent reagent serves as an excellent fluoroalkylation agent for various amines and nitrogen heterocycles.