Base-Promoted Formal [4 + 3] Annulation between 2<i>-</i>Fluoro­phenyl­acetylenes and Ketones: A Route to Benzoxepines

The first base-promoted formal [4 + 3] annulation between 2-fluorophenyl­acetylenes and ketones has been disclosed. The reaction proceeds through a tandem α-vinylation of ketones followed by an intramolecular nucleophilic aromatic substitution (S_NAr) reaction of the <i>in situ</i> generated β,γ-unsaturated ketone intermediates, providing a straightforward access to a wide range of functionalized benzoxepines in moderate to high yields. The transition-metal-free methodology featured a wide substrate scope, the use of easily available starting materials, and a high functional group tolerance

Base-Promoted Formal [4 + 3] Annulation between 2<i>-</i>Fluoro­phenyl­acetylenes and Ketones: A Route to Benzoxepines

The first base-promoted formal [4 + 3] annulation between 2-fluorophenyl­acetylenes and ketones has been disclosed. The reaction proceeds through a tandem α-vinylation of ketones followed by an intramolecular nucleophilic aromatic substitution (S_NAr) reaction of the <i>in situ</i> generated β,γ-unsaturated ketone intermediates, providing a straightforward access to a wide range of functionalized benzoxepines in moderate to high yields. The transition-metal-free methodology featured a wide substrate scope, the use of easily available starting materials, and a high functional group tolerance