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Book The Synthesis Characterization and Reactivity of First row Late Transition Metal Complexes Containing Tridentate Pincer type N heterocyclic Phosphenium Ligands

Download or read book The Synthesis Characterization and Reactivity of First row Late Transition Metal Complexes Containing Tridentate Pincer type N heterocyclic Phosphenium Ligands written by Sadie E. Knight and published by . This book was released on 2015 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Late Transition Metal Complexes Containing Tridentate Pincer type 1 3 bis o diphenylphosphino Phenyl N N heterocyclic Phosphenium carbene Ligands

Download or read book Late Transition Metal Complexes Containing Tridentate Pincer type 1 3 bis o diphenylphosphino Phenyl N N heterocyclic Phosphenium carbene Ligands written by Baofei Pan and published by . This book was released on 2006 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Synthesis and Reactivity of Transition Metal Complexes Bearing the Tridentate Bis 2 mercapto p tolyl amine SNS H 3 Ligand

Download or read book Synthesis and Reactivity of Transition Metal Complexes Bearing the Tridentate Bis 2 mercapto p tolyl amine SNS H 3 Ligand written by Kyle Evan Rosenkoetter and published by . This book was released on 2017 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work described herein focuses on the synthesis and characterization of new heterobimetallic complexes containing the redox-active W[SNS] 2 metalloligand and investigation into their electronic properties and reactivity. Most recent studies have explored the redox nature of the [SNS]H 3 scaffold through the synthesis and reactivity of a novel set of square-planar nickel complexes.Chapters 2 and 3 describe a modular synthetic approach towards generating a new series of heterobimetallic complexes with the general formula W[SNS]2M(L) ([SNS] = bis(2-mercapto- p-tolyl)amine; M = Ni, Pd, or Pt; and L = dppe, depe, dmpe, dppp, PR'2NRPR'2 (R = phenyl, benzyl; R'=phenyl), DPEphos or dppf). The complexes were prepared by a salt metathesis of Cl2MII(L) with the previously reported W[SNS]2 coordination complex under reducing conditions. X-ray diffraction analysis revealed interesting coordination geometries about the appended Group 10 metal centers moving from Pt and Pd (pseudo-square planar) to the first row Ni (pseudo-tetrahedral) analogue. These complexes demonstrate formal metal--metal bond formation across the series with a tunable first oxidation potential up to 600 mV.Chapter 4 investigates the use of W[SNS]2Ni(dppe) as a catalyst for the electrochemical reduction of protons to hydrogen. This complex was found to catalytically generate hydrogen with an overpotential of 700 mV, a TOF of 14 sec--1, and a Faradaic yield of 80 +/- 3 % using 4-cyanoanilinium tetrafluoroborate in non-aqueous solutions.Chapter 5 demonstrates the effect of exchanging the nickel center of the heterobimetallic complexes discussed in Chapters 2 and 3 with other first row transitions metal ions (i.e. cobalt and copper). Analysis into the observed metal--metal distances reveal stark differences across the series. Additionally, the copper ion containing complexes demonstrate dynamic behavior in solution.Chapter 6 investigates the synthesis and reactivity of a series of monomeric square-planar nickel complexes of the [SNS] scaffold to demonstrate the ligand as redox, proton, and hydrogen atom non-innocent.Appendix A illustrates the electrochemical responses observed for the monoanionic complexes from Chapter 6 in the presence of CO2 and CO. Appendices B and C describe the synthesis and characterization of a five-coordinate cobalt and a heterotrimetallic tungsten-nickel complex, respectively.

Book Synthesis Characterization and Reactivity of Novel Bis phosphinoamide Zr Co Heterobimetallic Complexes Bearing N isopropyl Phosphinoamide Ligands

Download or read book Synthesis Characterization and Reactivity of Novel Bis phosphinoamide Zr Co Heterobimetallic Complexes Bearing N isopropyl Phosphinoamide Ligands written by Nathaniel C. McCutcheon and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In light of growing environmental and economic concerns, there is a motivated effort to mimic the two-electron reactivity of precious transition metal complexes using more abundant, affordable, and non-toxic first row transition metals. The main challenge in this effort is that more sustainable first row transition metals do not readily undergo two-electron redox processes, which comprise many industrially relevant catalytic mechanisms, instead preferring to participate in one-electron reactions. One of several ways the Thomas group has approached this challenge is by tethering a Lewis acidic early metal to an electron-rich late metal via a bifunctional phosphinoamide ligand framework, allowing access to highly reduced late metal centers that have been shown to more favorably undergo two-electron redox processes. This thesis explores how the electron-donating properties of the phosphinoamide ligand impact the structure and reactivity of a novel series of bis(phosphinoamide) Zr/Co complexes. This series employs a more electron-donating iPrNPiPr2- ligand, as opposed to the XylNPiPr2- ligand previously featured in the group’s bis(phosphinoamide) Zr/Co systems. The relative electron density at the cobalt center is qualified using multiple spectroscopic and computational methods, and structural comparisons are made between analogous Zr/Co complexes bearing different ligands. These data are used to determine how increasing the electron-donating ability of the bis(phosphinoamide) framework impacts the thermodynamics of bond activation and the overall structure-reactivity relationship of Zr/Co complexes.

Book Synthesis Reactivity and Catalytic Applications of Two Coordinate First Row Transition Metal Complexes

Download or read book Synthesis Reactivity and Catalytic Applications of Two Coordinate First Row Transition Metal Complexes written by Michael Isaac Lipschutz and published by . This book was released on 2015 with total page 139 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recently, the development of more sustainable catalytic systems based on abundant first-row metals, especially nickel, for organic transformations has attracted significant interest. This thesis describes the development of new synthetic methods for the preparation of two-coordinate complexes of a variety of first row transition metals. The physical and spectroscopic properties of these complexes are discussed and the reactivity and catalytic applications of these compounds are also explored. Species of this type are found to catalyze a variety of useful organic transformations using inexpensive metals and ligands.

Book Synthesis Characterization and Reactivity of Heterobimetallic Transition Metal Complexes

Download or read book Synthesis Characterization and Reactivity of Heterobimetallic Transition Metal Complexes written by David Morris Hamilton and published by . This book was released on 1981 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Synthesis and Catalytic Application of PSiP and P N Ligated Complexes of First Row Metals

Download or read book Synthesis and Catalytic Application of PSiP and P N Ligated Complexes of First Row Metals written by Luke Murphy and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of PSiP pincer complexes of second- and third-row transition metals has led to the discovery of challenging bond activation chemistry as well as catalytic chemistry. While there now exists a considerable amount of literature regarding the behavior of PSiP complexes of the second- and third-row metals, comparatively little is known of the behavior of these ligands with the first-row metals. There has been a recent push toward the study of first-row transition metal chemistry in general, due to their high natural abundance and often lower toxicity when compared to their second- and third-row congeners. This document details progress toward the synthesis of a variety of novel Fe, Co and Ni complexes featuring PSiP ligation and application toward catalytic reduction of unsaturated substrates. In terms of (PSiP)Fe chemistry, considerable progress has been made toward the synthesis of novel coordination complexes, in particular the synthesis of hydride complexes of Fe. Organometallic hydride complexes are often implicated as important catalytic intermediates, and in this case a bis(dinitrogen) adduct of an Fe hydride has been identified as a highly active catalyst for the hydrogenation of olefins. Co chemistry with the same ligand has unveiled intriguing examples of both H2 and O2 bond cleavage chemistry, and again has led to an example of an alkene hydrogenation catalyst. A novel PSiP framework has been developed and applied toward chemistry of the group 10 transition metals, particularly nickel. In this regard, chemistry of complexes supported by this new ligand was found to be markedly different than that of similar complexes supported by the previous iteration of the ligand. In particular, a Ni hydride complex was successfully prepared and applied toward the selective reduction of CO2 to the formaldehyde level via hydroboration. Lastly, outside the realm of PSiP chemistry, a new monoanionic P,N-based ligand has been developed and its chemistry has been explored with respect to Fe and Co. Interesting coordination chemistry has been observed with this new ligand, and examples of reactive Fe and Co complexes have been obtained and applied toward the challenging reduction of tertiary amides to amines via catalytic hydrosilylation.

Book Low coordinate Terphenyl Transition Metal Complexes M

Download or read book Low coordinate Terphenyl Transition Metal Complexes M written by Chengbao Ni and published by . This book was released on 2009 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Synthesis and Reactions of Dinuclear Transition Metal Complexes Containing Bridging Ligands Relevant to Heterogeneous Catalysis

Download or read book Synthesis and Reactions of Dinuclear Transition Metal Complexes Containing Bridging Ligands Relevant to Heterogeneous Catalysis written by Eric Niels Jacobsen and published by . This book was released on 1986 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Transition Metal Complexes with Multidentate Phosphorous nitrogen Ligands Synthesis Characterization and Reactivity

Download or read book Transition Metal Complexes with Multidentate Phosphorous nitrogen Ligands Synthesis Characterization and Reactivity written by Sergio Santiago Rozenel and published by . This book was released on 2011 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract Transition metal complexes with multidentate phosphorous/nitrogen ligands. Synthesis, characterization and reactivity. By Sergio Santiago Rozenel Doctor in Philosophy in Chemistry University of California, Berkeley Professor John Arnold, Chair Chapter 1: Chromium complexes supported by the multidentate monoanionic ligand [N2P2] {H[N2P2] = tBuN(H)SiMe2N(CH2CH2PiPr2)2} are presented, and the activity of these complexes towards ethylene oligomerization/polymerization is examined. The complexes [N2P2]CrCl2 (1) and [N2P2]CrCl (2) polymerized ethylene after activation with MAO. Derivatives of 1 and 2 were synthesized in order to gain insights about the active species in the ethylene oligomerization/polymerization processes. The alkyl complexes [N2P2]CrMe (3), [N2P2]CrCH2SiMe3 (4) and [N2P2]Cr(Cl)CH2SiMe3 (5), the cationic species {[N2P2]CrCl}BF4 (7), {[N2P2]CrCl}BPh4 (8) and {[N2P2]CrCH2SiMe3}BF4 (9), and the Cr(II) complex [N2P2]CrOSO2CF3 (11) were not active ethylene oligomerization/polymerization catalysts in absence of an activator. Reaction of 1 with two equivalents of MeLi led to reduction to 3. However, with one equivalent of MeLi the stable mixed alkyl-halide derivative [N2P2]Cr(Cl)Me (6) was obtained. Reaction of 2 with Red-Al® produced the hydride ([N2P2]Cr)2(ì-H)2 (10), which reacted with CO to produce the Cr(I) complex [N2P2]Cr(CO)2 (12). Reduction of 2 with KC8 in the presence of p-tolyl azide produced the dimeric cis μ-imido ([N2P2]Cr)2(ì-NC7H7)2 (13). A similar reduction in the presence of ethylene resulted in the isolation of the Cr(III) metallacyclohexane compound [N2P2]CrC4H8 (14). Chapter 2: A series of Co, Ni and Cu complexes with the ligand HN(CH2CH2PiPr2)2 (HPNP) has been isolated and their electrochemical behavior investigated by cyclic voltammetry. The nickel complexes [(HPNP¬)NiOTf]OTf and [(HPNP)NiNCCH3](BF4)2 display reversible reductions, as does the related amide derivative (NP2)NiBr. Related copper(I) and cobalt(II) derivatives were isolated and characterized. Addition of piperidine to [(HNP2)NiNCCH3](BF4)2 led to the formation of the new species [(HPNP)Ni(N(H)C(CH3)NC5H10)](BF4)2. Nucleophilic addition of piperidine to acetonitrile to produce HN=C(CH3)NC5H10 was catalyzed by [(HPNP)NiNCCH3](BF4)2. Chapter 3: A series of bimetallic ruthenium complexes [HPNPRu(N2)]2(μ-Cl)2](BF4)2 (2), [(HPNPRu(H2)Cl)2(μ-Cl)2](BF4)2 (3), [(HPNPRu)2(μ-H2NNH2)(μ-Cl)2](BF4)2 (4), [(HPNPRu)2(μ-Cl)2(μ-HNNPh)](BF4)2 (5), [HPNPRu(NH3)(ç2-N2H4)](BF4)Cl (6), [(HNP2Ru)2(μ-Cl)2(μ2-OSO2CF3)]OSO2CF3 (7), [HPNPRu]2(μ-Cl)3]BPh4 (8) and [HPNPRu]2(μ-Cl)3]BF4 (9) were isolated and characterized in the course of reactions aimed at studying the reduction of N2 and hydrazine. Complex 4 produces ammonia catalytically from hydrazine, and complex 2 generates ammonia upon reaction with Cp2Co/HLuBF4. DFT calculations support the idea that the diazene complex formed is more stable than the expected Chatt-type intermediate. Chapter 4: The reduction chemistry of cobalt complexes with the PNP ligand was explored. Reaction of (HPNP)CoCl2 (1) with n-BuLi generated the deprotonated Co(II) product (PNP)CoCl (2), and the Co(I) reduced species (HPNP)CoCl (3). The reaction of complex 2 with KC8 was investigated, where it was found that the products obtained depended upon the inert gas used to carry out the reaction: (PNP)CoN2 (4) under N2, bimetallic complex [(PNP)Co]2 (5) under Ar, and (HPNP)Co(H)3 (8) under H2. Complex 5 reacted with H2 to generate the bimetallic complex [(PNP)CoH]2 (6). With H2, H3SiPh and AgBPh4 complex 3 generated the species (HPNP)CoCl(H)2 (9), (HPNP)CoCl(H)SiH2Ph (10) and [(HPNP)CoCl]BPh4 (11) respectively. DFT calculations were performed to gain insights about the transformations observed.