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New nickel and copper bisdithiolene complexes were prepared as tetraphenylphosphonium (Ph4P+) salts, (Ph4P)n[M(3cbdt)2], [n = 1, 2; M = Ni, Cu; 3cbdt = 3-cyanobenzene-1,2-dithiolate]: (Ph4P)2[Ni(3cbdt)2] (1); Ph4P[Ni(3cbdt)2] (2); (Ph4P)2[Cu(3cbdt)2] (3); Ph4P[Cu(3cbdt)2] (4), and characterised by single crystal X-ray diffraction, cyclic voltammetry, EPR and static magnetic susceptibility for the paramagnetic species. These Cu and Ni complexes obtained as stable monoanionic and dianionic anions are the first members of this family of cyano benzene functionalized bisdithiolene transition metal complexes, opening the way to the preparation of analogous compounds with other transition metals and their future use as building blocks for the preparation of molecular materials. Their properties are discussed in comparison with the corresponding complexes based on the 4-cyanobenzene-1,2-dithiolate (4cbdt) ligand previously described by us. The salts (Ph4P)n[M(3cbdt)2], [n = 1, 2; M = Ni, Cu] present the metal complexes always in a square-planar coordination geometry with a ligand trans configuration, but revealing a rich polymorphism. The Ni and Cu compounds are isostructural and occur as two polymorphs (α, β) with the exception of the salt of the monoanionic Ni complex, that was found only as the α-polymorph. The salt of the dianionic Ni complex was found to crystallise also with one acetonitrile molecule, when recrystallised from this solvent. The salts of monoanionic [Ni(3cbdt)2] and dianionic [Cu(3cbdt)2] complexes have been characterised by EPR and static magnetic susceptibility as paramagnetic S = 1/2 species. [ABSTRACT FROM AUTHOR]

The porous metal–organic framework UiO-66(Zr) obtained via non modulated synthesis, has revealed to be a notable heterogeneous catalyst, enabling extremely fast and very efficient desulfurization of a multicomponent model diesel and also a real diesel fuel. [ABSTRACT FROM AUTHOR]

A novel method to prepare silica nano-sized particles incorporating polyoxometalates was developed leading to a new efficient heterogeneous oxidative catalyst. Zinc-substituted polyoxotungstate [PW11Zn(H2O)O39]5− (PW11Zn) was encapsulated into silica nanoparticles using a cross-linked organic–inorganic core, performed through successive spontaneous reactions in water. The potassium salt of PW11Zn and the composite formed, PW11Zn-APTES@SiO2, were characterized by a myriad of solid-state methods such as FT-IR, FT-Raman, 31P and 13C CP/MAS solid-state NMR, elemental analysis and SEM-EDS, confirming the integrity of the PW11Zn structure immobilized in the silica nanoparticles. The new composite has shown to be a versatile catalyst for the oxidation of olefins and also to catalyze the desulfurization of a model oil using H2O2 as the oxidant and acetonitrile as the solvent. The novel composite material was capable of being recycled without significant loss of activity and maintaining its structural stability for consecutive desulfurization and olefin oxidative cycles. [ABSTRACT FROM AUTHOR]

The application of cobalt sepulchrate (sep) complexes as active and robust homogeneous catalysts is reported here for the first time, as well as the crystal structure of the [Co(sep)]2(SO4)3·10H2O compound. The reaction chosen to investigate the catalytic performance of these catalysts was the oxidation of styrene due to the importance of its products in various industrial applications. Sustainable experimental conditions were selected, using H2O2 as the oxidant and ionic liquids as solvents. A similar catalytic activity was found using complexes containing different anions: [Co(sep)]Cl3 and [Co(sep)]2(SO4)3. Different kinetic profiles were found using different ionic liquids (1-butyl-3-methylimidazolium hexafluorophosphate or tetrafluoroborate) or acetonitrile as solvents. Complete conversions were achieved after 24 h of reaction. Benzaldehyde was the main product formed and in some cases the only one observed. The homogeneous cobalt catalysts using an ionic liquid as solvent could be recycled for consecutive cycles without significant loss of activity. In addition, the stability of the cobalt sepulchrate complex was confirmed by 1H NMR after catalytic use. [ABSTRACT FROM AUTHOR]