Download or read book Synthesis and Characterization of Iron Dinitrosyl Complexes with Nitrogen Containing Chelating Ligands written by Derrick A. Diego and published by . This book was released on 2014 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Three new [Fe-NO]1U+007b complexes coordinated with nitrogen chelating ligands have been synthesized and characterized. The new synthesized complexes are dinitrosyl(2-2'-biquinoline)iron(O), dinitrosyl(2,2' -bipyridine 4,4' -dimethyl)iron(0), and dinitrosy 1(2,2'-bipyridine 4,4' -diphenyl)iron(0). Each complex is synthesized utilizing a common starting material, dinitrosyldicarbonyliron(0), (Fe(NO)2(CO)2). Reaction conditions are in an inert atmosphere at ambient temperature and pressure. The characterizations of these molecules are done with ultraviolet visible spectroscopy, infrared spectroscopy, and single crystal X-ray diffraction. Ultraviolet visible spectroscopy display metal ligand charge transfers between 250-550 nm. Peaks below this are due to intraligand transitions from the chelating ligands. Infrared spectroscopy data reveal that NO stretching frequencies shift to lower wavenumbers when compared to Fe(NO)2(CO)2 due to its better U+0076-donating abilities of the nitrogen chelating ligands. Single crystal X-ray diffraction data show that all complexes are pseudo tetrahedral in an attracto conformation.
Download or read book Synthesis and Characterization of Novel Dinitrosyl iron Complexes of Bridged Bis phosphine Ligands written by Karol L. Sytwu and published by . This book was released on 2014 with total page 85 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The purpose of this research is to synthesize novel dinitrosyl-iron complexes and to investigate their structures and properties. It is hoped that the compounds may be used for nitric oxide releasing agents in the biological system. Three novel dinitrosyl-iron complexes of bridged bis-phophine ligands were synthesized. Syntheses of the compounds were performed in the glove box under a nitrogen environment. The synthesized compound has general molecular formula of Fe2(NO)4(CO)2(L) where (L = ( - )-1,2-Bis[(2S,5S)-2,5-dimethylphospholano]ethane, ( - )-1,2-Bis((2R,5R)-2,5-diphenylphospholano)ethane, Bis(dicyclohexylphosphino)methane). These compounds were characterized using X-ray crystallography and spectroscopic methods of infrared (IR), ultraviolet-visible (UV-Vis), and nuclear magnetic resonance (NMR). FT-IR spectrum showed the formation of these complexes, UV-Vis analyses demonstrated the compounds characteristics, and the presence of compounds were detected by 1H and 13C NMR.
Download or read book Synthesis and Characterization of Iron Dinitrosyl Chelate Complexes written by Phuong-Mai Nguyen and published by . This book was released on 2002 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis of some dinitrosyl iron complexes with chelating ligands written by Negar Jourabchian and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Synthesis and Structural Characterization of Main Group and Transition Metal Complexes Supported by Nitrogen Based Ligands written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitrogen based monodentate and bidentate chelating ligands have captured a significant interest due to their ability to coordinate to a wide variety of elements. The â-diketimine, â-ketoiminato, formamidine, pyridineselenolate, and pyrazinecarboxamide ligands have all been employed in this study to further investigate the coordination preferences among main group and transition metals. Steric and electronic properties of these ligands can easily be altered by manipulating the substituents attached, thus leading to predictable structures with potential for many useful and significant applications. Investigations have shown that temperature, solvent, and metal halide employed are all key factors in the reaction outcomes. All of the complexes obtained throughout these studies have been characterized by X-ray crystallography along with other spectroscopic techniques, including NMR, IR, UV/Vis, and M/S. â-diketiminato ligands, [{N(R)C(Me)}2C(H)] where R = Dipp, Mes, commonly referred to as nacnac, have played an important role in the synthesis of novel pnictogenium complexes. Results show that through manipulation of the halide precursor, reaction stoichiometry, and the R substituent on the nacnac both N, N'- and N, C'-metal chelated complexes can be achieved. Additionally, â-ketiminato ligands, [RN(H)(C(Me))2C(Me)=O] where R = Dipp, and [RN(H)C(Me)CHC(Me)=O] where R = C2H4NEt2, have been studied. Both ligands were investigated with a range of d and p block metal halides and alkyls in order to compare and contrast the bulky, flexible, and even multi-dentate nature of each ligand. The preferred metal geometry remains constant for products with either ligand, but the steric protection offered by the individual ligands governs the nuclearity of the products, ranging from tetrameric cages to simple adducts. The formamidinate ligand, [RN(H)C(H)NR] where R = Dipp, was employed in synthesizing several aluminum and zinc complexes. In addition to their numerous applications as cata.
Download or read book Synthesis and Characterization of Dinitrosyl Iron Complexes Containing Phenanthroline Derivatives written by Cyrus Andrew Koroni and published by . This book was released on 2019 with total page 107 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Reactions involving Fe(NO)2(CO)2 with a series of phenanthroline derivatives were investigated and their products were characterized using IR, NMR, X-ray, UV/vis, CV and EPR. Infrared spectroscopy showed NO shifts of 1684 and 1607 cm-1, 1687 and 1632 cm-1, and 1675 and 1626 cm-1, for products 1, 2 and 3, respectively. X-ray crystal data revealed that all three complexes were of the attracto conformation with the nitric oxide, N-Fe-N, angles of
Download or read book Synthesis and Characterization of Metal Complexes with Sulfur and Nitrogen containing Ligands written by Claire MacLeod Ohman and published by . This book was released on 2001 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Low coordinate Iron I and Iron II Compounds as Model Complexes for Nitrogenase written by Karen Patricia Chiang and published by . This book was released on 2011 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Nitrogenase is an enzyme capable of catalyzing the reduction of molecular dinitrogen to the bioavailable form ammonia (NH3). Despite extensive research on the enzyme, where and how substrates bind remains a mystery. The iron-molybdenum cofactor (FeMoco) is the active site of the enzyme and contains six four-coordinate iron atoms. It is hypothesized that these iron centers become three-coordinate under reduction of the enzyme to bind N2. This has motivated groups to synthesize and study low-coordinate iron complexes to mimic the potential binding site. Chapter 2 presents a series of three- and four-coordinate iron(II) complexes with nitrogen, chlorine, oxygen, and sulfur ligands. The electronic variation is explored by measuring the association constant of the neutral ligands, and the reduction potential of the iron(II) complexes. The binding constants and the reduction potentials are surprisingly insensitive to changes in an anionic spectator ligand. This suggests that three-coordinate iron(II) complexes may have similar binding trends as proposed three-coordinate iron(II) intermediates in the FeMoco of nitrogenase. 1H-ENDOR (Electron-Nuclear Double Resonance) spectroscopy on an intermediate of a nitrogenase mutant suggests the presence of an iron hydride. However, one obstacle in identifying the binding mode (eg. terminal or bridging) of the hydride is the lack of ENDOR characterization of hydride complexes for spectroscopic comparison. Chapter 3 reports a high-spin, dimer iron(I)-hydride complex. Addition of potassium cation chelating agents to the dimer sequesters the potassium cation, and it was possible to isolate the first examples of monomeric, high-spin, iron(I)-hydride complexes. The chapter discusses the synthesis and characterization of these novel complexes and highlights possible applications as a model complex for spectroscopic comparisons to nitrogenase. The catalyst used for the industrial method (Haber-Bosch process) of forming NH3 from N2 contains iron, potassium, calcium, and aluminum oxides. The mechanism in this process is also unclear. Chapter 4 discusses the synthesis and characterization of iron(I) aryloxide complexes and their reactivity towards N2. These results suggest that preorganization of the iron centers and the presence of potassium cations can help facilitate reactivity towards N2"--Page ix-x.
Download or read book Dinitrosyl Iron Complexes as a Working Form of Nitric Oxide in Living Organisms written by Anatoly F. Vanin and published by Cambridge Scholars Publishing. This book was released on 2019-09-30 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book sums up the results of more than 50 years’ work on the physico-chemical characteristics and biological activities of dinitrosyl iron complexes (DNIC). The interest of researchers in DNIC increased dramatically after the discovery of the fundamental role of the DNIC constituent nitrogen monoxide (NO) as one of the most universal regulators of metabolic processes occurring in living organisms. By virtue of their ability to donate NO and nitrosonium ions (NO+), DNIC mimic their beneficial (regulatory) and detrimental (cytotoxic) effects on living organisms and represent their “working” form. This text will appeal to practitioners in the field of biology, and other areas of modern-day science.
Download or read book Synthesis Characterisation and Transition Metal Complexes of Nitrogen containing Ligands written by Stephanie Holland and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High and Low Valent tris N Heterocyclic Carbene Iron Complexes written by Carola S. Vogel and published by Springer Science & Business Media. This book was released on 2012-02-03 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carola Vogel’s PhD thesis focuses on the synthesis, and structural and spectroscopic characterization of the first high valent iron nitride complexes. In her interdisciplinary and collaborative research Carola also describes the reactivity studies of a unique iron (V) nitride complex with water. These studies show that quantitative yields of ammonia are given at ambient conditions. High valent iron nitride and oxo species have been proposed as key intermediates in many bio-catalytic transformations, but until now these species have proven exceedingly challenging to isolate and study. Iron complexes in high oxidation states can thus serve as models for iron-containing enzymes to help us understand biological systems or aid our development of more efficient industrial catalysts.
Download or read book The Synthesis and Characterization of New Iron Coordination Complexes Utilizing an Asymmetric Coordinating Chelate Ligand written by and published by . This book was released on 1995 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: A binuclear, unsymmetric coordinating ligand that is an effective metal chelator has been designed and synthesized. The new ligand has been shown to react readily with iron(II)/(III) forming a variety of coordination complexes. The binuclear complexes are of significant interest since they represent proof-of-principle for the development of coordinatively asymmetric, binuclear metal chelate compounds. Although this structural type of chelator now appears to be common in biological systems, it has not been previously described for inorganic coordination chemistry. The isolation of oxidation products will be helpful in establishing reaction mechanism(s) of these complexes with molecular oxygen. It is expected that this ligand and derivatives of it will play an important role in the development of bioinorganic complexes that aim to mimic enzyme active sites that function by substrate interaction at only one metal site of a multimetal active site.
Download or read book Synthesis and Characterization of Iron Complexes Supported by Bulky Amide Ligands written by Sheree Lynell Stokes and published by . This book was released on 1998 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis and Characterization of Manganese and Iron Complexes of the Dibenzophospholyl Ligand written by Melanie A. Neil and published by . This book was released on 2001 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transition Metal Dinitrogen Complexes written by Yoshiaki Nishibayashi and published by John Wiley & Sons. This book was released on 2019-05-06 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive book that explores nitrogen fixation by using transition metal-dinitrogen complexes Nitrogen fixation is one of the most prominent fields of research in chemistry. This book puts the focus on the development of catalytic ammonia formation from nitrogen gas under ambient reaction conditions that has been recently repowered by some research groups. With contributions from noted experts in the field, Transition Metal-Dinitrogen Complexes offers an important guide and comprehensive resource to the most recent research and developments on the topic of nitrogen fixation by using transition metal-dinitrogen. The book is filled with the information needed to understand the synthesis of transition metal-dinitrogen complexes and their reactivity. This important book: -Offers a resource for understanding nitrogen fixation chemistry that is essential for explosives, pharmaceuticals, dyes, and all forms of life -Includes the information needed for anyone interested in the field of nitrogen fixation by using transition metal-dinitrogen complexes -Contains state-of-the-art research on synthesis of transition metal-dinitrogen complexes and their reactivity in nitrogen fixation -Incorporates contributions from well-known specialists and experts with an editor who is an innovator in the field of dinitrogen chemistry Written for chemists and scientists with an interest in nitrogen fixation, Transition Metal-Dinitrogen Complexes is a must-have resource to the burgeoning field of nitrogen fixation by using transition metal-dinitrogen complexes.
Download or read book Synthesis Characterization and Reactivity of Iron Complexes with N donor Ligands in Relation to Oxygenation of Hydrocarbons written by Remle Çelenligil-Çetin and published by . This book was released on 2004 with total page 766 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Synthesis and Characterization of Redox noninnocent Pyrazine diimine Iron Complexes and an Inverted Pyridine diimine Ligand written by Jaylan Billups and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cooperativity between the metal center and the ligand has been shown in nature to be an important feature of systems that catalyze two-electron processes that first-row transition metals usually cannot catalyze on their own. In these cases, the ligand acts as a site of reactivity that in many instances can store electrons or react directly with substrates in solution. The design and study of systems where there is synergy between the metal and the ligand have been leveraged to catalyze polymerization and hydrogenation-type reactions as well as the activation of small molecules such as dihydrogen. Specifically, the pyridine(diimine) ligand scaffold has been reported to store up to three electrons on the ligand backbone that can later be used in catalysis. Wanting to expand on this work, we have designed and synthesized a new pincer that has redox-noninnocent properties similar to pyridine(diimine) ligands but incorporates a pyrazine ring instead of a pyridine ring to give rise to new electronic properties. Pyrazine(diimines) also have an uncoordinated 4-position nitrogen that can be further functionalized to fine-tune the electronic properties of the ligand. In Chapter II we will discuss bisligated iron(II) pyrazine(diimine) (PZDI) complexes in three different oxidation states where we used spectroscopic and computational techniques as well as comparison to known pyridine(diimine) iron(II) complexes to support our assignments of ligand-based reduction. Chapter III will focus on monoligated pyrazine(diimine) iron(II) complexes as compared to analogous pyrazine(diimine) systems where the central metal is manganese, cobalt, or nickel, as well as compare our pyrazine(diimine) iron(II) complexes to reported pyridine(diimine) iron(II) analogs. We have also synthesized a new inverted pyridine(diimine) ligand scaffold that has an NCN binding pocket, which will be discussed in Chapter IV. In the design of the inverted pyridine(diimine) ligand we have left in place the 4-position nitrogen from our previously described pyrazine(diimine) ligand, maintaining a Lewis basic site for functionalization. Overall, we hope to describe the results we observed with both monoligated and bisligated iron(II) pyrazine(diimine) complexes as well as discuss our approach to the design of and progress towards a new inverted pyridine(diimine) ligand scaffold.
