Molecular Hydride Carbonyl Clusters and Nanoclusters

This minireview outlines the actual status of the chemistry of hydride metal carbonyl clusters (MCCs) by means of pertinent examples, without being comprehensive. Section 1 gives a brief introduction to the topic. Section 2 describes the major synthetic routes for the introduction of hydride ligands in MCCs. Section 3 deals with the structures of hydride MCCs and the different coordination modes of hydride ligands. Section 4 presents some general considerations on 1H NMR studies of hydride MCCs, including fluxionality and the problems of detecting hydrides in larger MCCs. Section 5 deals with electrochemical studies of hydride MCCs, focusing on electrochemistry as an indirect tool for determining the hydride nature of large MCCs, and tuning the redox potentials of MCCs by protonation/deprotonation reactions. Section 6 describes some applications of hydride MCCs in catalysis and electrocatalysis. General conclusions are reported in Section 7.