One-Carbon Ring Expansion of Indoles and Pyrroles: A Straightforward Access to 3-Fluorinated Quinolines and Pyridines

3-Fluorinated quinolines and pyridines are prevalent pharmacophores, yet their synthesis is often challenging. Herein, we demonstrate that dibromofluoromethane as bromofluorocarbene source enables the one-carbon ring expansion of readily available indoles and pyrroles to structurally diverse 3-fluorinated quinolines and pyridines. This straightforward protocol requires only a short reaction time of ten minutes and can be performed under air atmosphere. Preliminary investigations reveal that this strategy can also be applied to the synthesis of other valuable azines by using different 1,1-dibromoalkanes as bromocarbene sources. 1,1-Dibromoalkanes as bromocarbene sources make one-carbon ring expansion of indoles and pyrroles facile, allowing for direct access to structurally diverse azines, especially the pharmaceutically important 3-fluorinated quinolines and pyridines. This straightforward protocol features bench-stable reagents, a broad range of substrates, and good compatibility with various functional groups.image