Substitution of the acetonitrile ligands in Fe₄Cu₂C(CO)₁₂(MeCN)₂ with bidentate L–L ligands, such as 4,4′-bipyridine (bipy), pyrazine (pyz) or p-dicyanobenzene (p-DCB), gives rise to either infinite [Fe₄Cu₂(μ₆-C)(CO)₁₂(μ-L–L)]_∞ zigzag chain polymers or to [Fe₄Cu₂(μ₆-C)(CO)₁₂(μ-L–L)]₄·8THF square oligomers, as a function of the crystallization solvent.

The combined steam/dry reforming of clean biogas (CH₄/CO₂ = 50/50 v/v) represents an innovative way to produce synthesis gas (CO + H₂) using renewable feeds, avoiding to deplete the fossil resources and increase CO₂ pollution. The reaction was carried out to optimize the reaction conditions for the production of a syngas with a H₂/CO ratio suitable for the production of methanol or fuels without any further upgrading. Ni-Rh/Mg/Al/O catalysts obtained from hydrotalcite-type precursors showed high performances in terms of clean biogas conversion due to the formation of very active and resistant Ni-Rh bimetallic nanoparticles. Through the utilization of a {Ni₁₀Rh(CO)₁₉}{(CH₃CH₂)₄N}₃ cluster as a precursor of the active particles, it was possible to promote the Ni-Rh interaction and thus obtain low metal loading catalysts composed by highly dispersed bimetallic nanoparticles supported on the MgO, MgAl₂O₄ matrix. The optimization of the catalytic formulation improved the size and the distribution of the active sites, leading to a better catalyst activity and stability, with low carbon deposition with time-on-stream.

The hetero-metallic [Sb@Rh12(CO)27]3− cluster has been known as for over three decades thanks to Vidal and co-workers, and represents the first example of an E-centered (E=heteroatom) icosahedral rhodium carbonyl cluster. However, its synthesis required high temperature (140–160°C) and elevated CO pressure (400atm). Applying the redox condensation method for cluster preparation, we herein report a new synthetic, high-yield route for preparing [Sb@Rh12(CO)27]3− under much milder conditions of temperature and pressure. Notably, when the same synthesis was carried out under N2 instead of CO atmosphere, the new isostructural but unsaturated derivative [Sb@Rh12(CO)24]4− was obtained, for which we report the full X-ray structural characterization. This species represents one of the few examples of an icosahedral cluster disobeying the electron-counting Wade-Mingos rules, possessing less than the expected 170 cluster valence electrons (CVEs). Judging from IR monitoring, the two species can be obtained one from the other by switching between N2 and CO atmosphere, making [Sb@Rh12(CO)27]3− a spontaneous CO-releasing molecule. Finally, the study of the chemical reactivity of [Sb@Rh12(CO)27]3− with PPh3 allowed us to obtain the new [{Sb@Rh12Sb(CO)25}2Rh(CO)2PPh3]7− dimeric compound, for which we herein report the full X-ray structural and 31P NMR analyses