Tandem Oxidative Nucleophilic Hydrogen Substitution/B-O Cyclization Enables Chiral Near-Infrared N,O,B-Chelated BODIPYs.

We report a mild, modular tandem strategy that transforms readily available B-substituted BODIPYs into a new class of N,O,B-chelated BODIPYs with intense near-infrared absorption/emission. The key transformation involves oxidative nucleophilic substitution of α-hydrogens (ONSH) followed by intramolecular B-O cyclization, operating with diverse ketones (acetophenones, indanones, tetralones, acenaphthenone). X-ray crystallography reveals a tetrahedral boron center that is inherently stereogenic. Chiral resolution by HPLC and circular dichroism spectroscopy confirm the optical activity of the enantiomers.