Grafting Ta(NtBu)(CH2CMe2Ph)3 onto the surface of silica partially dehydroxylated at 300 °C leads to the formation of the surface imido complex (SiO)2Ta(NtBu)(CH2CMe2Ph) as a major species, which was characterized with EXAFS, 13C CP/MAS NMR, diffuse reflectance FTIR, elemental analyses, and chemical reactivity. The obtained material acts as an efficient heterogeneous catalyst for various oxo/imido heterometathesis transformations: imidation of ketones and DMF with N-sulfinylamines and condensation of N-sulfinylamines into sulfurdiimines and phenyl isocyanate into diphenylcarbodiimide.

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The trigonal-bipyramidal [Fe3Au2(CO)12(PPh3)2(μ3-O)] and octahedral [Fe3Rh3(CO)15(μ3-O)]- clusters have been obtained from the reaction between a triangular [Fe3(CO)9(μ3-O)]2- cluster and metal-containing compounds Au(PPh3)X (X = Cl, NO3) and [Rh(CO)2Cl]2, respectively. X-ray structural studies revealed that the addition of two Au(PPh3) or three Rh(CO)2 groups to [Fe3(CO)9(μ3-O)]2- resulted in clusters with a virtually unchanged Fe3(μ3-O) fragment.

In this work, the preparation and characterization of a novel multifunctional collagen–chitosan material containing silver nanoparticles and nonsteroid anti‐inflammatory drug ibuprofen is described. As a starting material, the commercially available collagen–chitosan scaffold was used. Drug‐loading procedure was performed via supercritical CO2‐assisted impregnation technique. Silver nanoparticles were prepared via metal vapor synthesis and introduced into the composite biopolymer matrix. An analysis of the small‐angle X‐ray scattering profiles revealed that silver nanoparticles are characterized by having a logarithmic normal size distribution with the maximum at 25 nm. The average size of particles determined from the broadening of diffraction peaks is in a good agreement with this result. The surface of the materials was characterized by X‐ray photoelectron spectroscopy. The in vitro release kinetics of ibuprofen in phosphate buffer solution with pH = 7.4 from prepared materials was studied. The drug release to solution is governed by Fickian diffusion and can be described within the Ritger–Peppas model. Introduction of silver nanoparticles has no effect on the diffusion mechanism. The as‐prepared materials are promising for the medical applications such as dressings for treatments of infected wounds and infection preventing. These materials can act as a matrix for transdermal drug administration. POLYM. ENG. SCI., 59:2479–2487, 2019. © 2019 Society of Plastics Engineers

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