Hydroxo-bridged copper(II) cubane complexes

Oxygen-bridged tetranuclear copper complexes having a Cu4O4 cubane-like core represent a really fascinating class of compounds, due to their similarity to copper oxidase active sites or to their molecular magnetism. Among these, hydroxo-bridged copper(II) cubanes are a restricted category when compared to alkoxo-bridged ones, {Cu4(μ3-OH)4}-based compounds structurally described via X-ray being only 18 (to the end of 2014), to the best of our knowledge. In this review, the key features of these compounds will be highlighted, with attention to their structural characterization and classification, their syntheses and their magnetic behavior.