Proposed equilibria involving multiple EuIII species with reactivity summarized under the species. The equilibria are based on luminescence-decay, steady-state luminescence measurements, and 1H-NMR data with reactivity and selectivity from Mukaiyama aldol reaction results. Adapted with permission from Averill, D. J.; Allen, M. J. Inorg. Chem. 2014, 6257. Copyright 2014 American Chemical Society