Fluorocyclisation of Oximes to Isoxazolines Through I(I)/I(III) Catalysis

A regioselective fluorocyclisation of β,γ-unsaturated oximes through I(I)/I(III) catalysis is disclosed to generate 5-fluoromethylated isoxazolines. The transformation leverages p-iodotoluene as an inexpensive catalyst, Selectfluor® the terminal oxidant and amine⋅HF complex (1 : 7.5) both fluoride Brønsted acid source. λ3-iodane p-TolIF2, which generated in situ, engages pendant alkene substrate facilitate a cyclisation/fluorination sequence. range 5-fluoromethyl isoxazolines can be using this method, including aliphatic aromatic systems (up 56 % yield). Single crystal X-ray analysis representative example reveals conformation that consistent with stereoelectronic gauche effect between exocyclic C(sp3)−F bond C(sp3)−O isoxazoline (ϕOCCF=−62.0°).