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Book Synthesis and Study of Coordination Compounds of Cobalt Copper Palladium and Nickel with Polydentate Ligands Containing Sulfur

Download or read book Synthesis and Study of Coordination Compounds of Cobalt Copper Palladium and Nickel with Polydentate Ligands Containing Sulfur written by Tatiana Straistari and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work focuses on the synthesis, the characterization and the catalytic evaluation in the reduction of protons into dihydrogen, of new complexes of Ni(II), Co(III), Cu(II) and Pd(II) based ligands Type thiosemicarbazone. The catalytically active species during the process of the proton reduction was studied by cyclic voltammetry and mechanisms were formulated on the basis quantum chemical calculation.The first chapter introduces the scientific context, the goals and the main objectives of this work. The second chapter concerns the synthesis and the characterization of the N2S2 ligands and their associated mononuclear complexes, Ni, Cu and Pd. The third chapter presents the synthesis and the characterization of binuclear Co and trinuclear Ni based on N2S2 ligand.Electrochemical studies of these complexes in DMF in the presence of a proton source (trifluoroacetic acid), allowed us to evaluate their catalytic efficiency. Our results show that Cu and Pd complexes have a specific irreversible wave for the reduction of protons, but decomposition is observed during electrolysis, which makes these uninteresting complexes for the reduction of protons.On the contrary, Ni and Co complexes showed an electrochemical stability and good catalytic performances. In particular, the new mononuclear Ni complex exhibits remarkable catalytic properties that rank it among the best catalysts for the reduction of protons reported in the literature. All this work provided a complete description of the electrochemical behavior of N2S2 thiosemicarbazone ligands complexed to transition metals. It allows considering future developments in improving the catalytic properties of these complexes.

Book Synthesis and Characterization of Mixed Donor Ligands and Their Corresponding Metal Complexes

Download or read book Synthesis and Characterization of Mixed Donor Ligands and Their Corresponding Metal Complexes written by Timothy Michael Erasmus Jugovic and published by . This book was released on 2017 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presented in this thesis is the synthesis and characterization of two new classes of mixed donor ligands, as well as several copper(II) and nickel(II) complexes. Chapter II details the synthesis and characterization of thiosemicarbazates, which are tridentate ONS (oxygen, nitrogen, sulfur) donor compounds. In Chapter III complexes of these thiosemicarbazate ligands with nickel(II) and copper(II) are prepared and characterized. Chapter IV discusses the synthesis and characterization of several different amidothiocrown and amidoazathiocrown ethers.

Book Pincer Compounds

    Pincer Compounds

    Book Details:
  • Author : David Morales-Morales
  • Publisher : Elsevier
  • Release : 2018-04-11
  • ISBN : 0128129328
  • Pages : 756 pages

Download or read book Pincer Compounds written by David Morales-Morales and published by Elsevier. This book was released on 2018-04-11 with total page 756 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pincer Compounds: Chemistry and Applications offers valuable state-of-the-art coverage highlighting highly active areas of research—from mechanistic work to synthesis and characterization. The book focuses on small molecule activation chemistry (particularly H2 and hydrogenation), earth abundant metals (such as Fe), actinides, carbene-pincers, chiral catalysis, and alternative solvent usage. The book covers the current state of the field, featuring chapters from renowned contributors, covering four continents and ranging from still-active pioneers to new names emerging as creative strong contributors to this fascinating and promising area. Over a decade since the publication of Morales-Morales and Jensen’s The Chemistry of Pincer Compounds (Elsevier 2007), research in this unique area has flourished, finding a plethora of applications in almost every single branch of chemistry—from their traditional application as very robust and active catalysts all the way to potential biological and pharmaceutical applications. Describes the chemistry and applications of this important class of organometallic and coordination compounds Includes contributions from global leaders in the field, featuring pioneers in the area as well as emerging experts conducting exciting research on pincer complexes Highlights areas of promising and active research, including small molecule activation, earth abundant metals, and actinide chemistry

Book Synthesis and Characterization of Nickel II Complexes of a Hydrotrispyrazolylborate Ligand and of Novel Phosphinetrithiol Ligands

Download or read book Synthesis and Characterization of Nickel II Complexes of a Hydrotrispyrazolylborate Ligand and of Novel Phosphinetrithiol Ligands written by Weihong Zhang and published by . This book was released on 1990 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Multidentate Phosphino alkene Ligands and Their Late Transition Metal Complexes

Download or read book Multidentate Phosphino alkene Ligands and Their Late Transition Metal Complexes written by Amanda G. Jarvis and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The synthesis and characterisation of a new class of multidentate conformationally flexible phosphino-alkene ligands, called dbaPHOS (127) and monodbaPHOS (128), are described is this PhD thesis. The related phosphine sulphide ligands, namely dbaTHIOPHOS (137) and monodbaTHIOPHOS (149), have also been prepared. The coordination chemistry of the novel ligands was investigated with a variety of late-transition metals, including Cu, Rh, Pd and Pt. X-ray crystal structure determination of the complexes containing these ligands highlights the multiple coordination modes and versatility of each ligand system. The ability of the 1,4-dien-3-one backbone to adopt different conformational geometries around metal centers is of particular note. DbaPHOS (127) was found to act as a cis- and trans-chelating bisphosphine in both square planar PdII and PtII complexes. The 1,4-dien-3-one motif is hemilabile; exchange between coordinated and non-coordinated alkenes is observed in both the Pd0 complex, 167, and the related cationic CuI complex, 193. An investigation into the CuI complexes' activity in the cyclopropanation of styrene, as catalysts, showed that they are commensurate with other recently reported systems. In addition to the coordination chemistry of the novel ligand systems, some interesting findings emerged in the ligand synthesis and characterisation studies. For example, monodbaTHIOPHOS (149) undergoes an interesting solid-state [2+2] intramolecular cycloaddition transformation, giving cycloadduct, 206. Furthermore, 2-hydroperoxytetrahydrofuran was found to be an impurity in the microwave-assisted Horner-Wadsworth-Emmons reaction of 2-(diphenylthiophosphine)benzaldehyde (136) with 1,3-bis-(ethoxyphosphonato)-acetone (130) to give of dbaTHIOPHOS (137) and an unexpected THF insertion product, 138. The latter is explained by a side reaction involving the reduced compound, tetrahydrofuran-2-ol, derived from 2-hydroperoxytetrahydrofuran.

Book Synthesis and Characterization of Nickel II Complexes of a Hydrotrispyrazolylborato Ligand and of the Thiosalicylato Ligand

Download or read book Synthesis and Characterization of Nickel II Complexes of a Hydrotrispyrazolylborato Ligand and of the Thiosalicylato Ligand written by Weibin Chen and published by . This book was released on 1994 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book British Reports Translations and Theses

Download or read book British Reports Translations and Theses written by British Library. Document Supply Centre and published by . This book was released on 1994 with total page 706 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issue for Mar. 1981 contains index for Jan.-Mar. 1981 in microfiche form.

Book The Synthesis and Characterisation of Macrocrylic Ligands with N O and S Donor Atoms and Related Transmission Metal Complexes of These Ligands

Download or read book The Synthesis and Characterisation of Macrocrylic Ligands with N O and S Donor Atoms and Related Transmission Metal Complexes of These Ligands written by Alison Mary Ingham and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The ligand 1-oxa-4,8-diazacyclodecane ([10]aneN2O) was synthesised, along with the [special characters omitted] complexes. Bis-ligand complexes are formed with facial coordination of the ligand to the transition metals, with two nitrogen donors from each ligand forming an equatorial plane around the metal ion. The crystal structure of [special characters omitted] was determined, as is described. The copper(II), nickel(II) and palladium(II) complexes have been characterised by FAB MS, electronic spectroscopy, elemental analysis and where possible by NMR and EPR spectroscopy. The nickel(II) and copper(II) complexes have distorted octahedral geometries, while the palladium(II) complex has square planar geometry with no observable axial interaction from the ether donors. The redox characteristics of the complexes formed have been determined, and are described within. The synthesis of the novel tricyclic ligand, 7,16-dioxa-1,4,10,13- tetraazatricyclo[11.5.3.3]octadecane [special characters omitted] is described. The [special characters omitted] conplex has been synthesised and characterised. The complex gives an unusually stable [special characters omitted] complex compared to complexes where a similar donor set is present A novel template synthesis was utilised to synthesise the bicyclic ligand 1,2-bis(1-oxa-5,8-diazacyclodecanyl)ethane ([special characters omitted] earmuff). This synthesis involved reaction of secondary amines which are coordinated to a copper(II) ion, a method which to our knowledge has not been used before in the synthesis of macrocyclic ligands. The copper(II) complex synthesised during this reaction has been characterised, and the redox reactions have been examined. The synthesis of 17-oxa-1,4,8,11-tetraazabicyclo[6.6.5]tetradecane (bicyclo[12-12] [special characters omitted]) is reported. Copper(II) and nickeI(II) complexes of this ligand have been synthesised and characterised. The chloride ion substitution reaction of [Ni(bicyclo[12-12] [special characters omitted] has been examined. The reaction was found to have an inverse dependence on the acid concentration. A tentative mechanism has been proposed to explain the origin of the acid dependence. The equilibrium constant for this reaction, determined by visible spectrophotometry, was found to be [special characters omitted]. The cobalt(III) bis-ligand complex of the previously synthesised ligand, 8-aza-1,5- dithiacyclodecane ([special characters omitted]) was synthesised. Under the conditions used, two isomers were formed - a facially coordinate bis-ligand complex where the equatorial plane is defined by two sulfur and two nitrogen donors, and a more symmetrical isomer where all four sulfur donors are coordinated equatorially. Isomerisation of the unsymmetrical isomer to the symmetrical isomer occurs in solution. The [special characters omitted] complexes of the ligand 1,2-bis(8-aza-1,5-dithiacycIodecanyI)ethane ([special characters omitted] earmuff) were synthesised and characterised. The ligand coordinates to [special characters omitted] in a pseudo five coordinate manner as determined by NMR spectroscopy. A solvent molecule or anion is likely to be coordinated to the [special characters omitted] centre in order to achieve distorted octahedral coordination. The complexes were characterised by FAB MS, electronic spectroscopy, elemental analysis and ESR spectroscopy. Although the [special characters omitted] centre was found to be in the low spin state, the electron transfer self exchange rate constant could not be determined by NMR spectroscopy. The [special characters omitted] complex of this ligand was also synthesised and found to coordinate in a five coordinate manner. Evidence of axial coordination of nitrogen in the palladium complex was observed in the electronic spectrum, therefore a distorted square pyramidal geometry has been proposed for the [[special characters omitted] earmuff)] complex. The potentially binuclear ligand, 1,9-bis(4-aza-1,8-dithiacyclononane)-4,7-diaza-2,8-dionenonane, was synthesised and characterised. Preliminary results indicate that reaction with two equivalents of nickel(II) produced a binuclear complex.