B-spiroBODIPYs as a fluorophore responsive to hydrogen bond donors

Abstract

Boron dipyrromethene (BODIPY) dyes possess excellent photophysical properties and are extensively used in chemical biology and materials science. While peripheral functionalisation of the dipyrromethene core is well established, modification at the boron centre has remained limited. Here, we demonstrate an Au-catalysed modulation of the boron centre, enabling the synthesis of B-spiroBODIPYs with a 1,3-dioxinone moiety on boron. The resulting B-spiroBODIPY exhibits solvent-dependent fluorescence arising from hydrogen-bonding interactions at the carbonyl oxygen on the 1,3-dioxinone moiety, offering a versatile platform for stimulus-responsive fluorescent probes.