Synthetic, Electrochemical, and Theoretical Studies of Tetrairidium Clusters Bearing Mono- and Bis[60]fullerene Ligands

Phosphine, isocyanide, and alkyne reactivity at pentanuclear molybdenum/tungsten–iridium clusters

Trigonal-bipyramidal molybdenum/tungsten–iridium clusters undergo ligand substitution with isocyanides and triphenylphosphine, and react with alkynes with CC cleavage or triiridium-face-specific addition.

Cyclic voltammetry modeling, geometries, and electronic properties for metallofullerene complexes withμ3-η2:η2:η2-C60bonding mode

Reduction potential (E(red)) values have been calculated and compared with available cyclic voltammetry (CV) data for 10 metallofullerene complexes with the mu(3)-eta(2):eta(2):eta(2)-C(60) (M(3)-C(6)[C(60)]) bonding mode. Consideration of bulk solvent effects is essential for the calculation of the E(red) values. Scaling factors for the electrostatic terms of the solvation energies have been introduced to fully describe the experimental cyclic voltammograms with a small mean deviation of 0.07 V. Multiple electron reductions induce movement of the metal cluster moieties on the C(60) surface, which is accompanied with the changes in some M-C[C(60)] bonds from pi-type to sigma-type mode. However, the changes in M(3)-C(60) distances, as well as the geometric changes of M(3) and C(60), are small for the reductions, which is in harmony with the high chemical and electrochemical stability of the metallofullerenes. Our population analyses reveal that the added electrons are not localized at the C(60) moieties, and electron population in the metal clusters is significant, more than 20% (av. 37%), for all the reductions. Furthermore, we demonstrated that the two close one-electron redox waves in CV diagrams are strongly correlated with significant electron delocalization, about 40-80%, to the metal-cluster moieties in these metallofullerene complexes.