The excited-state dynamics and energetics of a series of BODIPY-derived chromophores bound to a catechol at the boron position were investigated with a combination of static and time-resolved spectroscopy, electrochemistry, and density functional theory calculations. Compared with the difluoro-BODIPY-derived parent compounds, the addition of the catechol at the boron reduced the excited-state lifetime by three orders of magnitude. Deactivation of the excited state proceeded through an intermediate charge-transfer state accessed from the initial optically excited π∗ state in <1 ps. Despite differences in the structures of the BODIPY derivatives and absorption maxima that spanned the visible portion of the spectrum, all compounds exhibited the same, rapid, excited-state deactivation mechanism, suggesting the generality of the observed dynamics within this class of compounds.
Bibliographical noteFunding Information:
This work was supported by NSF (DMR-1708177), NSF (CHE-1464711), NSF MRI (MRI-1420373), the Minnesota Supercomputing Institute, NSERC, CFI, University of Manitoba, and WestGrid Canada.
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