Alumina-promoted oxodefluorination.

A simple protocol for the clean preparation of heterocyclic compounds containing dibenzofuran's core oxodefluorination of fluoroarenes on activated γ-AlO is reported. Alumina can be considered as a reliable oxygen source enabling one-pot substitution of fluorine atoms and yielding benzoannulated furan derivatives. The corresponding C-F bond activation is selective towards less stable C-Br/C-I and occurs under metal- and solvent-free conditions.