Metal-free intramolecular aminofluorination of alkenes mediated by PhI(OPiv)2/hydrogen fluoride-pyridine system.

A convenient, metal-free intramolecular aminofluorination of alkenes has been developed. Employing readily available PhI(OPiv)(2) and hydrogen fluoride-pyridine in the presence of BF(3)·OEt(2), tosyl-protected pent-4-en-1-amines were converted to 3-F-piperidines in one step in good yields as well as high stereoselectivity.