Low valent managanese complexes as functional models for the manganese catalases and the alternate catalase reaction of the oxygen evolving complex

Synthetic dinuclear manganese complexes were prepared as structural, spectroscopic, and functional models for manganese containing enzymes. We synthesized a series of manganese dimers with the invariant ligand set of the pentadentate N,N'-bis(salicylimino)-1,3-diaminopropan-2-ol (2-OHsalpn). The dimers prepared in this work formed as 1:1 Mn:L complexes with each ligand chelating both Mn ions bridged by the alkoxide oxygen. These complexes were isolated in the four known oxidation states of the manganese catalases: ;The ;We also examined the kinetics of H;These systems provide insight into the reaction chemistry of multinuclear manganese complexes and the mechanistic features observed for the Mn catalases and the alternate catalase reaction of the OEC.