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Showing 1 to 18 of 18 for “"Pincer ligand."”.
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Synthesis, Characterization And Reactivity Studies Of Nickel Complexes Supported By A Phosphinimine-Based Pincer Ligand
Tridentate pincer-type ligands offer both electronic and steric flexibility and have been used to stabilize highly reactive species, including late transition metal complexes with metal–ligand multiple bonds. Herein, we report a series of novel nickel complexes supported by a pincer-type …
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Catalytic hydrofunctionalization and small molecule reactivity at a low-valent cobalt center supported by a bis(carbene) CCC pincer ligand
… metal compounds, the presence of a weak ligand field engenders a high-spin electron configuration and one-electron events at the expense of two-electron elementary steps. Accordingly, our lab and many others have endeavored to utilize a strong ligand field approach whereby a …
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Early Transition Metal CCC-NHC Pincer Complexes: Synthesis, Characterization, and Catalysis
… methodology for the metalation of CCC-NHC pincer ligand precursors has been extended to other early-transition metals and ligands. Specifically, synthetic results for the preparation of imidazole based CCC-NHC pincer Ti (IV), CCC-NHC pincer Ta (V) will be discussed. In addition, the …
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Synthesis, Characterization And Application Of Pt Complexes With Pincer Ccc-Bis(Nhc) Ligands
… route for the synthesis of CCC-bis(NHC) pincer ligand supported transition metal complexes was extended to Pt. Several platinum complexes were synthesized. The identity of these complexes was confirmed through multiple technologies, including nuclear magnetic resonance spectroscopy, mass …
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Chemistry of highly reactive group 5 and 6 transition metal compounds
… the group 6 chemistry, the first [CCC] X₃-donor pincer ligand for a transition metal was synthesized by two consecutive cyclometalations of a terphenyl complex of the group 5 metal tantalum. Chapter 1 describes two new transformations that occur between W(PMe₃)₄(η²-CH₂PMe₂))H and haloarenes, …
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Effects of different ligands on the binding of a palladium center in a pyridyl spaced dicarbene
… is a pyridine bridged N-heterocyclic carbene pincer ligand. These compounds have been characterized by NMR and IR spectroscopies. Furthermore, X-ray crystallography has permitted the solid-state structures of these complexes to be determined. VT-NMR and IR experiments have allowed for the …
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Synthesis, characterization, and catalytic reactivity of first-row transition metal CCC pincer complexes
… in the desired reactions is to use strong-field ligand frameworks. Strong-field ligands cause the d-orbital splitting of the metal center to increase in energy, often leading to low-spin electronic configurations which favor two-electron reactivity. N-heterocyclic carbenes (NHCs) are popular …
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The catalytic hydrogenation of carbon-carbon and carbon-nitrogen multiple bonds by a cobalt(I) complex
… an electron-rich monoanionic bis(carbene) aryl pincer ligand, MesCCC, was chosen study two-election chemistry with cobalt. With the MesCCC pincer ligand platform well-suited to stabilize a range of oxidation states of cobalt (Co(III), Co(II), and Co(I)), studies into the room temperature …
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SUSTAINABLE CATALYSIS VIA IRON AND ZINC COMPLEXES: FROM TUNABLE METALLATE SYSTEMS TO PHOTOCHEMICAL REACTIVITY
… macrocyclic pyclen based iron complexes. These ligands stabilize iron centers in well defined oxidation and spin states, allowing detailed spectroscopic characterization and controlled photochemical reactivity. Mössbauer spectroscopy proved essential for resolving ambiguities arising from …
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Ligand Cooperative Iridium PCP Complexes for Small Molecule Activation
… This thesis presents the synthesis of a new PCP pincer ligand framework bearing benzo[b]thiophene linking groups as an alternative to the parent ortho-phenylene linkers. This ligand was installed onto an iridium center via double C-H activation at the central carbon atom, resulting in a carbene …
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Catalytic Activity of Molybdenum-Dioxo Complexes
… supported by a dianionic meridional pincer ligand. Rational substrate scope was explored using aliphatic diols, aromatic diols, and biomass derived diols. Various reductants were tested for ability to catalyze the reaction. The substrate specific mechanism of DODH was explored …
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Earth-Abundant Metal Complexes Binding N-Heterocyclic Carbene-Based Ligands for the Photocatalytic Carbon Dioxide Reduction Reaction
… achieve this goal. N-heterocylic carbene (NHC) ligands have been used widely in organometallic catalyst applications owing to its strong sigma-donor properties that can enhance the stability of the transition metal-based catalysts. The combination of an NHC-based ligand with a pyridyl ring to …
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Ligand design in nickel and cobalt complexes for homogeneous catalysis
… for a monoanionic, bidentate NHC-CAryl ligand framework ([H(BrCC)]Br) were developed. The metalation of this ligand precursor with nickel was achieved by both initial metalation with Ni(II) followed by reduction and direct metalation with Ni(0). The presence of a Ni-CAryl bond in the …
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Low-temperature protonation studies of transition metal alkyl complexes and the synthesis and characterization of early transition metal PCP pincer complexes and two-coordinate alkylamido complexes
… studies, the procedures to synthesize the DFMPM ligand and the Cp*Os(DFMPM)Br intermediate have been improved. A laboratory-scale procedure was developed to synthesize diethylzinc in which the α-CH2 positions are isotopically labeled with carbon-13 and/or deuterium; these reagents were then …
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Developments of time-resolved XAFS spectroscopy techniques - applications in homogeneous catalysis
… of substituents at the para-position of the NCN-pincer ligand benzene ring allows one to tune the metal center of the complex electronically and consequently the reactivity of the catalytically active pincer. In Chapter 5 we have used the Atomic XAFS contributions in the Pt L2,3 XAFS spectra of …
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The gas chromatographic separation properties of azulene and the synthesis and characterization of bulky bis-pyrazolylpyridine metal-ligand complexes.
… and characterization of bulky tridentate ligand-metal complexes. Azulene is an aromatic molecule with interesting properties, most notably a permanent dipole moment of 1.08 D. This degree of polarity in the absence of heteroatoms is quite rare and offers potential for use in unique gas …
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Supported catalysts, from polymers to gold nanoparticles supports
… that are used in this thesis, the palladium pincer complex and the palladium N-heterocyclic complex. In chapter 3, the synthesis of a soluble polymer supported catalyst is described. The polymer chosen for the study is poly(norbornene), and the catalyst is a 1,3-disubstituted benzene ligand …