Search results for "bimetallic"
showing 10 items of 187 documents
Catalytic CO oxidation over pumice supported Pd–Ag catalysts
2001
Abstract Results on the catalytic oxidation of CO at 523 K over bimetallic Pd–Ag catalysts supported on pumice are reported and compared with those obtained from the monometallic Pd and Ag catalysts. The catalysts were prepared by organometallic precursors and were characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) after different treatments with air and with hydrogen. The activity of the catalysts decreases with increasing Ag/Pd atomic ratio, the monometallic palladium exhibiting the highest activity. Furthermore, the treatment with air and with hydrogen always results in a better catalytic performance. On the basis of the structural characterization by XRD…
ChemInform Abstract: Mono(cyclopentadienyl) Complexes of the Rare-Earth Metals
2010
I. Introduction 1953II. Overview of Synthesis, Structure, and Properties 1954A. Synthetic Methods 1954B. Ligands and Structures 1955III. Halo Complexes 1956A. General 1956B. Divalent Halo Complexes 1956C. Trivalent Halo Complexes 1957IV. Chalcogenido Complexes 1958A. General 1958B. Divalent Chalcogenido Complexes 1958C. Trivalent Chalcogenido Complexes 1959V. Pnicogenido Complexes 1960A. General 1960B. Divalent Amido and Phosphido Complexes 1960C. Trivalent Pnicogenido Complexes 19611. Bis(amido) Complexes 19612. Mixed Halo and Chalcogenido Complexes 1962VI. Hydrocarbyl and Silyl Complexes 1963A. General 1963B. Divalent Complexes 19631. Metallacarbaboranes 19632. Bimetallic Naphthalene Comp…
Inside Back Cover: First Step Towards a Devil's Staircase in Spin-Crossover Materials (Angew. Chem. Int. Ed. 30/2016)
2016
International audience; Periodic and aperiodic spin-state concentration waves form during “Devil's staircase”-type spin-crossover in a new bimetallic 2D coordination polymer {Fe[(Hg(SCN)3)2](4,4′-bipy)2}n. In their Communication on page 8675 ff., J. A. Real, E. Collet et al. describe the appearance of spin-state concentration waves between long-range spatially ordered structures of low- and high-spin states during multistep spin-crossover.
Charge-transfer driven by ultrafast spin-transition in a CoFe Prussian blue analogue
2020
Photoinduced charge-transfer is an important process in nature and technology and is responsible for the emergence of exotic functionalities, such as magnetic order for cyanide-bridged bimetallic coordination networks. Despite its broad interest and intensive developments in chemistry and material sciences, the atomic-scale description of the initial photoinduced process, which couples intermetallic charge-transfer and spin transition, has been debated for decades; it has been beyond reach due to its extreme speed. Here we study this process in a prototype cyanide-bridged CoFe system by femtosecond X-ray and optical absorption spectroscopies, enabling the disentanglement of ultrafast electr…
Pd-Cu catalysts supported on anion exchange resin for the simultaneous catalytic reduction of nitrate ions and reductive dehalogenation of organochlo…
2019
International audience; The present work proposes the simultaneous removal of these classes of pollutants by a catalytic hydrotreatment processes. For this purpose, bimetallic Pd-Cu catalysts (with mass ratio Pd:Cu of 4:1) supported on macroporous strong base anion resin were prepared by different methods. The catalysts were characterized (by XRD, SEMEDX, XPS, AAS and H-2 chemisorption) and tested in a continuous flow system. The selected catalyst preparation protocol consists in a two-step method, which implies the deposition of palladium by ion exchange and the subsequent deposition of copper by controlled reaction on the surface of the pre-reduced palladium. The effectiveness of the cata…
Tuning the Basicity of Synergic Bimetallic Reagents: Switching the Regioselectivity of the Direct Dimetalation of Toluene from 2,5‐ to 3,5‐Positions
2008
Meta-meta metalation: Remarkably, toluene can be directly dimanganated or dimagnesiated at the 3,5-positions using bimetallic bases with active Me3SiCH2 ligands (see scheme, blue). In contrast, n-butyl ligands lead to 2,5-metalation (red). tmp=2,2,6,6-tetramethylpiperidide.
Metallomacrocycles with metalmetal bonds: synthesis, characterization and electrochemistry of [(P)SnRe(CO)5]BF4 and [{(P)Sn}2Re(CO)4]BF4 derivatives…
1996
Abstract The synthesis and characterization of bimetallic and trimetallic porphyrins of the type [(P)SnRe(CO) 5 ]BF 4 and [{(P)Sn} 2 Re(CO) 4 ]BF 4 are reported where P is the dianion of tetra- p -tolyporphyrin (TpTP) or tetra- m -tolyporphyrin (TmTP). These metal-metal bonded complexes were synthesized by reaction of Re 2 (CO) 10 with the corresponding (P)SnCl 2 derivatives in 1,2-dichlorobenzene followed by a reaction with NaBF 4 or TBABF 4 in toluene to give the BF − 4 salt. Each compound was characterized by a variety of spectroscopic and electrochemical techniques while the structures were assigned on the basis of FAB mass spectral data and by comparison of their physicochemical proper…
Magnetic phase transition and magnetic bistability in oxamato-based CoIICuII bimetallic MOF thin films
2019
Abstract Thin films of an anionic oxamato-bridged cobalt(II)–copper(II) 3D MOF have been growth at 120 °C in DMSO through a one-pot reaction from Co(NO3)2·6H2O and (Me4N)2[Cu(2,6-Et2pa)2]·6H2O (2,6-Et2pa = N-2,6-diethylphenyloxamate) over Si(111) surfaces functionalized with carboxylic acid terminating groups. These heterobimetallic CoII2CuII3 MOF thin films (2) of about ten nanometers thickness show a ferrimagnetically ordered phase below ca. 10 K with a relatively large magnetic hysteresis similar to that of the bulk material of formula (Me4N)2[Co2Cu3(2,6-Et2pa)6]·5H2O (1).
Anticancer study of heterobimetallic platinum(II)-ruthenium(II) and platinum(II)-rhodium(III) complexes with bridging dithiooxamide ligand
2019
Abstract Three heterobimetallic platinum (II)/ruthenium (II) and platinum (II)/rhodium (III) complexes, A: Pt{S–S2C2(NR)2H}{μ-S2C2(NR)2}-[Ru (p-cymene)Cl], R = isoamyl; B: Pt{S–S2C2(NR)2H}{μ-S2C2(NR)2}[Rh (phpy)2], R = isoamyl; C: [Pt{S–S2C2(NR)2H}{μ-S2C2(NR)2}-[Rh(C5Me5)Cl]], R = benzyl, were prepared from mononuclear complexes 1 and 2, 1: [Pt (H-isoamyl2DTO)2]; 2: [Pt (H-benzyl2DTO)2], DTO = dithiooxamide, by reaction of 1 or 2 with the corresponding chlorido-bridged dimers, [Rh(C5Me5)Cl (μ-Cl)]2, [Ru (p-cymene)Cl (μ-Cl)]2 or [Rh (phpy)2 (μ-Cl)]2, and then evaluated as anticancer agents for the inhibition of the three proteolytic activities of human 20S proteasome, one of the main target …
2D and 3D bimetallic oxalate-based ferromagnets prepared by insertion of MnIII-salen type complexes
2013
The syntheses, structures and magnetic properties of the compounds of formulae [Mn((R)-salmen)(CH3OH)(CH3CN)][MnCr(ox)3](CH3OH)0.5(CH3CN)1.25 ((R)-1), [Mn((S)-salmen)(CH3OH)(CH3CN)][MnCr(ox)3](CH3OH)0.5(CH3CN)1.25 ((S)-1), [Mn((R)-salmen)(CH3OH)2][MnCr(ox)3](CH2Cl2)0.375(CH3OH)0.125(H2O)0.375 ((R)-2) and [Mn((S)-salmen)(CH3OH)2][MnCr(ox)3](CH2Cl2)0.375(CH3OH)0.375(H2O)0.125 ((S)-2) (ox = oxalate, salmen2− = N,N′-(1-methylethylene)bis(salicylideneiminate)), [Mn(salpn)(CH3OH)1.5(CH3CN)0.5][MnCr(ox)3](CH3OH)0.82(H2O)0.93 (3) (salpn2− = N,N′-(propane)bis(salicylideneiminate)) and [Mn(saltmen)(CH3OH)(CH3CN)][MnCr(ox)3](CH3OH) (4) (saltmen2− = N,N′-(1,1,2,2-tetramethylethylene)bis(salicylideneimi…