Half-sandwich complexes of platinum group metals (Ir, Rh, Ru and Os) and some recent biological and catalytic applications

Plasmon-induced Ag decorated CeO2 nanorod array for photodetector application

In this work, glancing angle deposition (GLAD) has been used to grow Ag decorated CeO₂ nanorod (NR) array on n-type Si substrate. The length of the NRs obtained was ∼235 nm and the size of the Ag NPs varied from 13 to 41 nm. The polycrystalline and crystalline nature of CeO₂ and Ag respectively was revealed via selected area electron diffraction (SAED) analysis as well as x-ray diffraction (XRD) pattern. Optical absorption measurement depicts a distinct broad peak around 413 nm that is ascribed to the localized surface plasmon resonance (LSPR) effect of Ag NPs. The Ag decorated CeO₂ NR device exhibited a turn on voltage at ∼3.2 V under dark, which then reduced to ∼1.3 V under 35 min illumination along with the increase in device current from 2.8 to 24.5 μA cm^-2 (4 V) on continuous exposure to light. Under white light illumination, a responsivity of 4.51 A W^-1 was obtained at 370 nm along with the detectivity and noise equivalent power (NEP) values of 4.15 × 10¹² jones and 0.01 pW respectively. Additionally, a fast response characteristic with rise and fall times of 74 ms and 42 ms respectively was demonstrated. Thus, these findings manifest the underlying LSPR mechanism at work in Ag/CeO₂ heterojunction and reveal its high potential in UV photodetector application.

Crystal structure of chlorido-(η 6-p-cymene)-(N-(2-fluorophenyl)-1-(pyridin-2-yl)methanimine-κ 2 N,N′)ruthenium(II) – acetone (1/1), C22H23ClN2F7OPRu

C22H23ClN2F7OPRu, monoclinic, P21/c (no. 14), a = 7.30480(10) Å, b = 12.9540(3) Å, c = 28.7076(6) Å, β = 96.6990(10)°, V = 2697.95(9) Å3, Z = 4, R gt(F) = 0.0196, wR ref(F 2) = 0.0479, T = 100(2) K.

Open clamshell dinuclear palladium(ii) complexes possessing out-of-plane anisotropy

Double cyclometalation of planar, oligomeric phenylpyridines yielded dinuclear palladium(ii) complexes with novel out-of-plane anisotropy. An X-ray crystal structure analysis revealed that the complexes exhibit concave-convex geometry, and 1H NMR measurement evidenced the occurrence of stable out-of-plane anisotropy. The dipole moment and Pd-Pd interaction were investigated by theoretical calculations.

Crystal structure of η6-p-cymene-iodido-(N-isopropyl-1-(pyridin-2-yl)methanimine-κ2 N,N′)ruthenium(II) hexafluorophosphate(V), C19H26IN2F6Ru

C19H26IN2F6Ru, triclinic, P1̄ (no. 2), a = 9.240(2) Å, b = 10.019(3) Å, c = 12.689(3) Å, α = 78.921°, β = 81.596(10)°, γ = 83.654°, V = 1136.30(5) Å3, Z = 2, R gt(F) = 0.0174, wR ref(F 2) = 0.0440, T = 173 K.

FeNi3 magnetic nanoparticles supported on ruthenium silicate-functionalized DFNS for photocatalytic CO2 reduction to formate

For aerobic oxidation, anchoring ruthenium(ii) in the nanospaces of magnetic dendritic fibrous nanosilica (DFNS) afforded a potential nanocatalyst (the complex FeNi₃/DFNS/Ru(ii)), which showed enhanced activity. The FeNi₃/DFNS/Ru(ii) complex exhibited excellent catalytic activity in the reduction of carbon dioxide to formate in the presence of visible-light irradiation. We have analyzed its characteristics by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), a vibrating sample magnetometer (VSM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA).

For aerobic oxidation, anchoring ruthenium(ii) in the nanospaces of magnetic dendritic fibrous nanosilica (DFNS) afforded a potential nanocatalyst (the complex FeNi₃/DFNS/Ru(ii)), which showed enhanced activity.

Facile Arene Ligand Exchange in p-Cymene Ruthenium(II) Complexes of Tertiary P-Chiral Ferrocenyl Phosphines

Half-sandwich arene-metal complexes are commonly used for specific applications. Herein, we report facile arene ligand exchange reactions of two ruthenium(II) complexes of tertiary P-stereogenic ferrocenyl phosphines. By mild photochemical activation, the displacement of p-cymene and subsequent tethering by η⁶-coordination of the terminal phenyl ring of a biphenylyl-substituted ferrocenyl phosphine were enabled. Furthermore, the spontaneous p-cymene displacement in a 2-methoxyphenyl-containing ferrocenyl phosphine and ensuing coordination of the ligand as a P,O chelate were examined. For both reactions, theoretical calculations of the general course of the reaction confirmed the experimental findings. The ease of the controlled arene displacement reported here can offer new pathways for the synthesis and design of novel tailor-made catalysts.

Half-sandwich ruthenium(ii) complexes with tethered arene-phosphinite ligands: synthesis, structure and application in catalytic cross dehydrogenative coupling reactions of silanes and alcohols

The preparation of the tethered arene-ruthenium(ii) complexes [RuCl₂{η⁶:κ¹(P)-C₆H₅(CH₂)_nOPR₂}] (R = Ph, n = 1 (9a), 2 (9b), 3 (9c); R = ⁱPr, n = 1 (10a), 2 (10b), 3 (10c)) from the corresponding phosphinite ligands R₂PO(CH₂)_nPh (R = Ph, n = 1 (1a), 2 (1b), 3 (1c); R = ⁱPr, n = 1 (2a), 2 (2b), 3 (2c)) is presented. Thus, in a first step, the treatment at room temperature of tetrahydrofuran solutions of dimers [{RuCl(μ-Cl)(η⁶-arene)}₂] (arene = p-cymene (3), benzene (4)) with 1-2a-c led to the clean formation of the corresponding mononuclear derivatives [RuCl₂(η⁶-p-cymene){R₂PO(CH₂)_nPh}] (5-6a-c) and [RuCl₂(η⁶-benzene){R₂PO(CH₂)_nPh}] (7-8a-c), which were isolated in 66-99% yield. The subsequent heating of 1,2-dichloroethane solutions of these compounds at 120 °C allowed the exchange of the coordinated arene. The substitution process proceeded faster with the benzene derivatives 7-8a-c, from which complexes 9-10a-c were generated in 61-82% yield after 0.5-10 h of heating. The molecular structures of [RuCl₂(η⁶-p-cymene){ⁱPr₂PO(CH₂)₃Ph}] (6c) and [RuCl₂{η⁶:κ¹(P)-C₆H₅(CH₂)_nOPⁱPr₂}] (n = 1 (10a), 2 (10b), 3 (10c)) were unequivocally confirmed by X-ray diffraction methods. In addition, complexes [RuCl₂{η⁶:κ¹(P)-C₆H₅(CH₂)_nOPR₂}] (9-10a-c) proved to be active catalysts for the dehydrogenative coupling of hydrosilanes and alcohols under mild conditions (r.t.). The best results were obtained with [RuCl₂{η⁶:κ¹(P)-C₆H₅(CH₂)₃OPⁱPr₂}] (10c), which reached TOF and TON values up to 117 600 h^-1 and 57 000, respectively.

Synthesis and characterization of a novel ruthenium(ii) trisbipyridine complex magnetic nanocomposite for the selective oxidation of phenols

Anchoring ruthenium(ii) trisbipyridine complex [Ru(Bpy)₃]²⁺ into a magnetic dendritic fibrous silica nanostructure produces an unprecedented strong nanocatalyst, FeNi₃/DFNS/[Ru(Bpy)₃]²⁺.