Protonation and Dehydration Reactions of the Mn₄O₄L₆ Cubane and Synthesis and Crystal Structure of the Oxidized Cubane [Mn₄O₄L₆]⁺: A Model for the Photosynthetic Water Oxidizing Complex

Abstract

The synthesis and atomic structure of [Mn4O4L6]+(CF3SO3-), 1+OTf- (L = diphenylphosphinate), is reported. This new model for the photosynthetic water oxidizing complex extends the known [Mn4O4]n+ cubane core type to the Mn4(III,3IV) oxidation state. Synthesis of this cluster is achieved by one-electron oxidation of Mn4O4L6 (1) by molecular oxygen in a series of steps initiated by the protonation or silylation of one oxide bridge in 1.