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Book Synthesis Characterization and Reactivity of Ni II Complexes Stabilized by an Intramolecular Hydrogen Bonding Network

Download or read book Synthesis Characterization and Reactivity of Ni II Complexes Stabilized by an Intramolecular Hydrogen Bonding Network written by Darla A. Powell-Jia and published by . This book was released on 2010 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metalloenzymes are able to perform a wide variety of difficult chemical transformations in a highly selective and efficient manner. The ability of metal complexes to perform a particular chemical reaction is dependant on the properties of the primary and secondary coordination environments. Development of transition metal complexes that catalyze the formation of organic compounds in a selective and highly efficient manner is of interest to synthetic chemists. Advancement in this area of research requires studies aimed at developing ligands that will give desirable properties upon binding to a metal ion. Using interactions present in biological systems, the ligands in this study have been developed to investigate the effects of the primary coordination sphere as well as hydrogen bonding interactions on complex formation as well as reactivity. Chapter 2 discusses the synthesis of terminal monomeric NiII-OH complexes with H41R. The hydroxo ligand is stabilized by two intramolecular hydrogen bonding interactions and the source of the hydroxo ligand was confirmed to be water. Attempts to deprotonate the NiII-OH complex to form a NiII-oxo complex were unsuccessful. Treating the NiII-OH complexes with KOtBu afforded the alkoxide substituted product. NiII-siloxide complexes were isolated upon reaction of NiII-OH with K[N(TMS)2]. Chapter 3 features the synthesis of a series of Ni(II) complexes with H2pmb, which contains two carboxyamido units appended from pyridine rings. Four Ni(II) complexes were synthesized and structurally characterized. It was determined that the carboxyamido groups either provided intramolecular H-bonds or the carbonyl oxygen can bind directly to the metal center. Chapter 4 explores the electrochemistry of the Ni(II) complexes characterized in Chapter 3. Based upon the observed reduction potentials, the reduction chemistry of [NiIIH2pmb(Cl)2] was explored. Further reactivity of the reduced species was also explored with dioxygen. Preliminary reactivity studies will also be discussed.

Book The Organic Chemistry of Nickel

Download or read book The Organic Chemistry of Nickel written by P.W. Jolly and published by Elsevier. This book was released on 2012-12-02 with total page 417 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Organic Chemistry of Nickel, Volume II: Organic Synthesis describes the chemistry of the organonickel complexes and the use of nickel in organic synthesis. Composed of six chapters, this volume starts with discussions on the oligomerization, co-oligomerization, and polymerization of olefins, followed by short accounts of the mechanistically related isomerization and hydrogenation of olefins, as well as the hydrosilylation and hydrocyanation reactions. Chapter II examines the oligomerization of acetylene and substituted alkynes, the co-oligomerization of alkynes with olefins, the related oligomerization of allene, including a number of telomerization reactions involving alkynes or allenes. Chapters III and IV describe the oligomerization, co-oligomerization, and polymerization of butadiene and substituted 1,3-dienes. Chapter V explores the coupling of organic halides in the presence of stoichiometric amounts of zerovalent nickel complexes, and the nickel-catalyzed cross-coupling reaction between organic halides and Grignard reagents. Lastly, Chapter VI emphasizes the carbonylation of alkynes, olefins, and organic halides using nickel complexes. This book will be of great value to organic chemists and researchers who are interested in the application of nickel complexes to organic synthesis.

Book Studies in Bioinorganic Chemistry

Download or read book Studies in Bioinorganic Chemistry written by Roxanne Michelle Jenkins and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: As inspired by the coordination environment of nickel in NikR and NiSOD, imidazole ligands were incorporated into N2SNiII square planar complexes in order to investigate the electronic and structural features of NiII species containing both imidazole and thiolate ligation. Rare examples of nickel complexes containing such ligand sets in continuous tetradentate (N2N'S) and discontinuous (N2S---N') coordination were synthesized and characterized. A significant finding in these studies is that the plane of the imidazole ligand is oriented perpendicular to the N2SNi plane. Further investigations addressed the orientational preference and stereodynamic nature of flat monodentate ligands (L = imidazoles, pyridine and an N-heterocyclic carbene) bound to planar N2SNi moieties. The solid state molecular structures of planar [N2SNiL]n+ complexes accessed through bridge-splitting reactions of dimeric, thiolate-S bridged [N2SNi]2 complexes, reveal that the plane of the added monodentate ligand orients largely orthogonal to the N2SNiL square plane. Variable temperature 1H NMR characterization of dynamic processes and ground state isomeric ratios of imidazole complexes in their stopped exchange limiting spectra, readily correlate with DFT-guided interpretation of Ni-L rotational activation barriers. Full DFT characterization relates the orientation mainly to steric hindrance derived both from ligand and binding pocket. In the case of the imidazole ligands a minor electronic contribution derives from intramolecular electrostatic interactions (imidazole C-2 C-H[superscript delta]- - S[superscript delta]− interaction). Our group has firmly established the versatility of the (bme-daco)2−, (bme-dach)2−, and (ema)4− ligands to accommodate a number of metals (M = Ni, Zn, Cu, and Fe), and have demonstrated reactivity of such N2S2M complexes occurs predominately at the S-thiolate sites. As vanadium is of interest for its biological, pharmacological and spectroscopic/analytical probe abilities, vanadyl analogues were explored as mimics of possible chelates formed from Cys-X-Cys binding sites in vivo. The structural and electronic changes from the incorporation of V=O2 in such dianionic and tetraanionic N2S2 binding pockets is investigated and compared to Ni2+ and Zn2+ in similar N2S2 environments. The nucleophilicity of the S-thiolate in these systems is explored with alkylating agents and W(CO)x. Furthermore, the vanadyl interaction with the CGC peptide, the biological analogue of the tetraanionic N2S2 ligand, was produced and characterized by EPR; its W(CO)x adducts were indentified by [upsilon](CO) infrared spectroscopy.

Book Synthesis and Characterization of Nickel II Compounds with Sulfur Donor Ligands

Download or read book Synthesis and Characterization of Nickel II Compounds with Sulfur Donor Ligands written by Li Zhou and published by . This book was released on 1995 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Synthesis Characterization and Reactivity of Ylidyne and Ylido Complexes Supported by Scorpionato Ligands

Download or read book Synthesis Characterization and Reactivity of Ylidyne and Ylido Complexes Supported by Scorpionato Ligands written by Priyabrata Ghana and published by Springer. This book was released on 2018-12-11 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book explores the development of the first open-shell heavier tetrylidyne complexes featuring a tetrel-centered unpaired electron, and unprecedented metallatetrylidynes containing a multiply-bonded, linear-coordinated single heavier tetrel atom embedded between two metal centers. The chemistry of compounds featuring triple bonds of the heavier Group-14 elements Si–Pb with transition metals is a very challenging research area, which combines modern molecular main-group element with transition-metal chemistry, and is of fundamental importance for the understanding of chemical bonding. During the last 15 years, the research in this area has witnessed considerable progress in isolating a series of closed-shell tetrylidyne complexes. However, despite numerous attempts, open-shell tetrylidyne complexes and heavier group 14 element congeners of metallacarbynes and carbide complexes remained inaccessible. In this book, readers will find more about the synthesis, full characterization and reactivity studies of these novel complexes that uncovered a plethora of exceptional products, including a novel m3-silicido complex, the first dimetallasilacumulene with a linear, two-coordinated single silicon atom and the first compounds of planar tetracoordinated silicon (ptSi) (Anti-van’t Hoff-Le Bell Silicon). Readers will also learn about the isolation and full characterization of the first room-temperature stable disilavinylidene, a silicon analogue of the very reactive vinylidenes (R2C=C:), and the first intermetallic plumbylidyne ligand transfer reactions.

Book Nickel Catalysis in Organic Synthesis

Download or read book Nickel Catalysis in Organic Synthesis written by Sensuke Ogoshi and published by John Wiley & Sons. This book was released on 2020-03-09 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive reference to nickel chemistry for every scientist working with organometallic catalysts Written by one of the world?s leading reseachers in the field, Nickel Catalysis in Organic Synthesis presents a comprehensive review of the high potential of modern nickel catalysis and its application in synthesis. Structured in a clear and assessible manner, the book offers a collection of various reaction types, such as cross-coupling reactions, reactions for the activation of unreactive bonds, carbon dioxide fixation, and many more. Nickel has been recognized as one of the most interesting transition metals for homogeneous catalysis. This book offers an overview to the recently developed new ligands, new reaction conditions, and new apparatus to control the reactivity of nickel catalysts, allowing scientists to apply nickel catalysts to a variety of bond-forming reactions. A must-read for anyone working with organometallic compounds and their application in organic synthesis, this important guide: -Reviews the numerous applications of nickel catalysis in synthesis -Explores the use of nickel as a relatively cheap and earth-abundant metal -Examines the versatility of nickel catalysis in reactions like cross-coupling reactions and CH activations -Offers a resource for academics and industry professionals Written for catalytic chemists, organic chemists, inorganic chemists, structural chemists, and chemists in industry, Nickel Catalysis in Organic Synthesis provides a much-needed overview of the most recent developments in modern nickel catalysis and its application in synthesis.

Book Sulfur rich Nickel Complexes

Download or read book Sulfur rich Nickel Complexes written by Patti Joann Riggs and published by . This book was released on 1990 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Aryl Substituted Imino N Heterocyclic Carbene Complexes Of Late Transition Metals

Download or read book Aryl Substituted Imino N Heterocyclic Carbene Complexes Of Late Transition Metals written by Anna Candace Badaj and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Nickel II Complexes Containing Non cyclic and Macrocyclic Ligands Derived Brom Benzil Monohydrazone

Download or read book Nickel II Complexes Containing Non cyclic and Macrocyclic Ligands Derived Brom Benzil Monohydrazone written by Courtney Michael Kerwin and published by . This book was released on 1972 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Synthesis Characterization and Reactivity of Various Imine Nickel II Complexes

Download or read book Synthesis Characterization and Reactivity of Various Imine Nickel II Complexes written by Daniel Beagan and published by . This book was released on 2016 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Macrocycle Ligand Modifications in the Pursuit of Nickel oxygen Complexes

Download or read book Macrocycle Ligand Modifications in the Pursuit of Nickel oxygen Complexes written by Joliene Renee Trujillo and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The utility of small molecules lies in the ability to alter the structure of the molecule and examine the spectroscopic characteristics as well as the reactivity of the complex. Small molecules are often used to probe mechanistic questions on much more complicated systems, such as enzymes. In 1996 a new form of superoxide dismutase was discovered which had nickel in the active site of the enzyme. This discovery sparked renewed interest in nickel-oxygen chemistry. Small molecules were used to probe different nickel-oxygen structure types and their spectroscopic characteristics, though complete understanding of the implications when altering the small molecules has yet to develop. This thesis addresses macrocycle ligand modifications, the varying ways of synthesizing nickel-oxygen complexes, and the reactivity of the nickel-oxygen adducts with exogenous substrates. The work presented herein, describes the synthesis and characterization of [Ni(tmcyclen)(CO)](OTf). Subsequent oxygen activation by [Ni(tmcyclen)(CO)](OTf) lead to the formation of "side-on" nickel(III) peroxo complex as determined by electronic absorption spectroscopy, electron paramagnetic resonance spectroscopy, and mass spectroscopy. Alternatively, the complex can be synthesized from nickel(II) and reduced oxygen reagents, H2O2 or KO2. Reactivity studies of the [Ni(tmcyclen)(O2)](OTf) with phosphines, sulfides, olefins, activated CH bonds, and substituted phenols were investigated. The reactivity studies completed on the "side-on" nickel(III)-peroxo complex shed light on the electronic characteristics of the complex. This thesis represents the first time a "side-on" nickel(III)-peroxo complex is synthesized from monovalent nickel and dioxygen.