C-F Bond Insertion into Indoles with CHBr₂F: An Efficient Method to Synthesize Fluorinated Quinolines and Quinolones

A mild and practical method for synthesizing fluorinated quinoline derivatives, which have a wide range of applications in pharmaceuticals, materials, and organic synthesis, was described through C-F bond insertion into indoles using CHBr2F. The simple conditions, readily availability of CHBr2F, as well as the versatility of the transformations make this strategy very powerful in synthesizing 3-fluoroquinoline and 3-fluoroquinolone. The mechanistic studies reveal that bromofluorocarbene generated in-situ under basic condition was the key intermediate.