Syntheses of Trifluoroethylated N-Heterocycles from Vinyl Azides and Togni's Reagent Involving 1,n-Hydrogen-Atom Transfer Reactions.

2,2,2-Trifluoroethyl-substituted 3-oxazolines, 3-thiazolines, and 5,6-dihydro-2H-1,3-oxazines have been obtained by reacting substituted vinyl azides with a combination of Togni's reagent and substoichiometric amounts of iron(II) chloride. The results of density functional theory calculations support the proposed mechanism involving 1,n-hydrogen-atom transfer reactions.