Cyclo-Tetrakis(μ-diphenylphosphido)-1,5-bis(tri-tert-butylphosphine)-Tetracopper

Copper phosphido compound Cu4(μ-PPh2)4(PtBu3)2 was synthesized by three synthetic methods and structurally characterized by X-ray diffraction and 1H, 31P, 13C and 31P HMBC NMR spectroscopy. Cu4(μ-PPh2)4(PtBu3)2 was also demonstrated to be a hydrophosphination pre-catalyst.

Nickel Phosphinidene Molecular Clusters from Organocyclophosphine Precursors

We report a new family of nickel phosphinidene molecular clusters synthesized from the reaction of bis(1,5-cyclooctadiene)nickel(0) ([Ni(cod)₂ ]) with organocyclophosphine and trialkylphosphine. We found that [Ni(cod)₂ ] cleaves the organocyclophosphine P-P bonds to generate phosphinidene groups, establishing the cyclic molecules as valuable precursors for making charge-neutral molecular clusters passivated by two-electron donor capping ligands. The formation of the cluster core structure is controlled by the bulkiness of the precursor and of the capping ligand. As a demonstration of this new cluster-forming reaction, we describe three clusters with different core nuclearity and degree of ligation: Ni₁₂ (PMe)₁₀ (PEt₃ )₈ , Ni₈ (PMe)₆ (PMe₃ )₈ , and Ni₈ (PiPr)₆ (PMe₃ )₆ . In addition, we show that the larger cluster, Ni₁₂ (PMe)₁₀ (PEt₃ )₈ , can be used as a low temperature single-source molecular precursor to the catalytically active nickel phosphide phase Ni₂ P.

Cu42Ge24Na4—A Giant Trimetallic Sesquioxane Cage: Synthesis, Structure, and Catalytic Activity

Unprecedented germanium-based sesquioxane exhibits an extremely high nuclearity (Cu42Ge24Na4) and unusual encapsulation features. The compound demonstrated a high catalytic activity in the oxidative amidation of alcohols, with cost-effective catalyst loading down to 400 ppm of copper, and in the oxidation of cyclohexane and other alkanes with H2O2 in acetonitrile in the presence of nitric acid. Selectivity parameters and the mode of dependence of initial cyclohexane oxidation rate on initial concentration of the hydrocarbon indicate that the reaction occurs with the participation of hydroxyl radicals and alkyl hydroperoxides are formed as the main primary product. Alcohols have been transformed into the corresponding ketones by the catalytic oxidation with tert-butyl hydroperoxide.

Enhanced thermal stability of Cu–silylphosphido complexes via NHC ligation

The thermal stability of the Cu–P(SiMe₃)₂ moiety can be enhanced via N-heterocyclic carbene ligation.

N-Heterocyclic carbene stabilized Ag–P nanoclusters

The N-heterocyclic carbene (NHC) 1,3-di-isopropylbenzimidazole-2-ylidene (ⁱPr₂-bimy) is found to be an excellent ligand for the stabilization of silver–phosphorus polynuclear complexes.

Synthesis and crystal structure of [tBu3SiPAg2]8: A novel Ag16-cluster featuring a remarkable symmetrical structure

The synthesis of [tBu3SiPAg2]8 which features an Ag16-cluster in the solid state was achieved by metathesis reaction of AgOCN with tBu3SiPNa2.

Translational Isomerism in Some Two- and Three-Station [2]Rotaxanes

The template-directed syntheses of three [2]rotaxanes are described. They all have dumbbell components, with both hydroquinone and resorcinol rings inserted into polyether chains terminated by tetraarylmethane stoppers, that become encircled during the key self-assembly processes by the tetracationic cyclophane, cyclobis(paraquat-p-phenylene), with its two pi-electron deficient bipyridinium units. It has been demonstrated by low-temperature (1)H NMR spectroscopy that the pi-electron deficient tetracationic cyclophane has a remarkably high preference to reside around the hydroquinone ring in these molecular shuttles. This observation illustrates how a very small constitutional difference-hydroquinone versus resorcinol recognition sites-can lead to the overwhelming preference for one translational isomer over another in this particular range of [2]rotaxanes.