An iron-catalyzed lactonization reaction via intramolecular
C(sp3)-H functionalization is described. The process employs
easily
accessible hydroxamate derivatives from which the noncommon insertion
of the oxygen occurred through a 1,5-hydrogen atom transfer. A mixture
of water and hexafluoroisopropanol as solvent appeared to be the key
parameter of this transformation to reach a high selectivity and efficiency.