Inorganic Chemistry Commons^™

Modulation Of Water-Exchange Rates Of Lanthanide(Iii)-Containing Complexes Using Polyethylene Glycol, Buddhima Nirodhi Siriwardena-Mahanama

Wayne State University Dissertations

MODULATION OF WATER-EXCHANGE RATES OF LANTHANIDE(III)-CONTAINING COMPLEXES USING POLYETHYLENE GLYCOL

by

BUDDHIMA N. SIRIWARDENA-MAHANAMA

May 2014

Advisor: Dr. Matthew J. Allen

Major: Chemistry

Degree: Doctor of Philosophy

A modular system of lanthanide(III)-containing polyethylene glycol (PEG) conjugates was synthesized and characterized to investigate the influence of length and density of PEG on water-exchange rates of lanthanide(III)-containing complexes. The water-exchange rates of lanthanide(III)-containing complexes contribute to the efficiency of these complexes as T₁-shortening and paramagnetic chemical exchange saturation transfer (PARACEST) contrast agents for magnetic resonance imaging (MRI). Because the mechanism of these two MRI methods is vastly different, there is …

Probing Proteasome Inhibition By Metal Copmplexes As A New Route For Anticancer Therapy, Dajena Tomco

Wayne State University Dissertations

The scope of this thesis is focused towards the development of metal-containing coordination compounds as potential therapeutic agents. Efforts of this research involve the design, synthesis, and purification of these complexes, as well as their evaluation by spectroscopic, spectrometric, and electrochemical characterization. The antineoplastic properties of these metal-containing pro-drugs are tested against the inhibition activity of the 26S proteasome. Selected metal ions ranging from transition to main group elements have been incorporated in various ligand systems containing phenolate and pyridyl donor sets. The mechanistic behavior of these complexes in solution has been thoroughly investigated along with their in vitro anticancer …

Redox-Active Trivalent Metallosurfactants With Low Global Symmetry For Molecule-Based Electronics: Spectroscopic, Electrochemical, And Amphiphilic Properties Of New Molecular Materials For Current-Voltage Measurements In M|Lb-Monolayer|M Devices, Lanka Dilruksi Wickramasinghe Wickramasinghe Arachchilage

Wayne State University Dissertations

LANKA D. W. WICKRAMASINGHE ARACHCHILAGE

August 2014

Advisor: Professor Cláudio N. Verani

Major: Chemistry (Inorganic)

Degree: Doctor of Philosophy

The silicon-based microelectronic industry has made remarkable technological advancements. Among these, new generation consumer electronics, telecommunication devices, and high performance data processing smart devices are of special interest. At present, electronic components existing on a single silicon chip grow rapidly, and soon the miniaturization process of electrical components will face limitations due to heat dissipation. Therefore, as an advanced alternative for silicon-based electronic components, the investigation of nanoscale molecular electronic devices is of great importance. This dissertation research is focused on …

Synthesis And Characterization Of Metal Complexes Containing Tetrazolate, Poly(Tetrazolyl)Borate, And Poly(Azolyl)Aluminate Ligands As High Energy Density Materials, Christopher James Snyder

Wayne State University Dissertations

A series of heavy alkaline earth metal tetrazolate complexes has been synthesized that contain metal ions saturated by aqua ligands. Tetrazolates with small ring-core carbon substituents favor formation of two dimensional polymers with u3-coordination of the tetrazolate to the metal centers. Tetrazolates with bulkier groups block coordination to the 1- and 4-nitrogen atoms, resulting in monomer formation. The first example of a trihydro(tetrazolyl)borate was prepared, and its bonding is heavily influenced by the basic BH3 moiety. 18-Crown-6 adducts of dihydrobis(tetrazolyl)borate complexes have been prepared that contain B-N bonding to the 2-nitrogen atoms, due to bulky ring-core atom substituents. A series …

Synthesis And Characterization Of Transition Metal Arsenide Nanocrystals And The Metastability And Magneto-Structural Phase Transition Behavior Of Mnas Nanocrystals, Yanhua Zhang

Wayne State University Dissertations

This dissertation study focuses on (1) probing the magneto-structural phase transformation in nanoscale MnAs; (2) evaluation of the size-dependent phase stability of type-B MnAs (prepared by rapid injection); and (3) developing a general synthetic method for transition metal arsenide nanoparticles.

Discrete MnAs nanoparticles that adopt different structures at room temperature (type-A, α-structure and type-B, β-structure) have been prepared by the solution-phase arrested precipitation method. Atomic pair distribution and Rietveld refinement were employed on synchrotron data to explore the structural transitions of the bulk and nanoparticle samples, and these results were compared to AC magnetic susceptibility measurements of the samples. The …

Synthesis, Spectroscopic, And Electrochemical Properties Of 3d Metal And Ruthenium Complexes With Phenolate And Catecholate Ligands, Frank Donald Lesh

Wayne State University Dissertations

The integration of amphiphilic properties into transition metal coordination systems is a pertinent step toward the development of candidate metallosurfactant precursors for the formation of responsive monolayer films. This concept is intended to preserve the solution-observed redox, spectroscopic, and magnetic responses onto solid surfaces for potential application. Selected metal ions and various ligand designs are investigated to address the effect of coordination and protonation preferences on amphiphilic behavior, the aspects of new modular approaches for Langmuir film precursors of differentiated topologies to extend amphiphilicity and redox behavior, and the introduction of photosensitizing properties into electroactive metallosurfactant precursors. In an attempt …

Synthesis And Characterization Of Size Controlled Transitionmetal Phosphide Nanoparticles And Their Hydrodesulfurization Catalytic Activity, Galbokka Hewage Layan Savithra

Wayne State University Dissertations

Transition metal phosphides are promising catalysts for hydrodesulfurization (HDS). The size-dependent catalytic activity of these metal phosphides for hydrodesulfurization (HDS) remains unstudied because the traditional temperature programmed reduction (TPR) method used in catalyst preparation results in highly polydisperse particles.

The main goals of this dissertation research are (1) synthesize metal phosphide nanoparticles (Ni²P, Rh²P, and Pd⁵P²) with control of size and morphology using a solution based arrested precipitation method; (2) develop large scale synthesis of mesoporous silica encapsulated nanoparticles (Ni²P and Pd⁵P²) with controlled loading to …

Synthesis And Characterization Of Group 5 Metal Complexes Containing Pyrazolate, Amidate, And Related Ligands As Potential Precursors For Thin Film Growth By Atomic Layer Deposition, Thuduwage Hiran Perera

Wayne State University Dissertations

Atomic Layer Deposition (ALD) is an advanced variant of Chemical Vapor Deposition (CVD) and is used to deposit smooth and conformal thin films for applications in the microelectronics industry. ALD requires metal precursors that are sufficiently volatile and thermally stable at elevated temperatures. Several group 5 ALD and CVD precursors were reported in the literature, which have been used to deposit TaN, NbN, Nb2O5, and Ta2O5 thin films. Synthesis of low and mid valent group 5 metal ALD precursors might give us access to deposit NbO2, Nb2O3, Ta2O3, and TaO2 thin films by low temperature ALD pathways upon applying mild …

Synthesis Of N-Acetyl And C-Tert-Butyl Natural Amino Acid Substrates That Mimic Residues Of Polypeptides And Their Reactivity With [Feiv(O)(N4py)]2+: Kinetic And Mechanistic Investigations, Ashley Ann Campanali

Wayne State University Dissertations

This dissertation is divided into two chapters, the first chapter includes an introduction to reactive oxygen species and their reactions with proteins. The introduction also covers metal-based oxidants, including both heme and non-heme enzymes that activate dioxygen as well as complexes that mimic these enzymes. The work discussed in chapter one concerns the synthesis of amino acid substrates that mimic amino acid residues. Substrates synthesized were derived from Gln, Asn, Ile, Cys and Tyr. Once synthesized, these substrates were reacted with [FeIV(O)(N4Py)]2+ under pseudo-first order conditions. The mechanisms for the reactions of the most reactive substrates were investigated. Electron-transfer proton-transfer …

Experimental And Theoretical Analysis Of The Electronic Behavior In Five-Coordinate Iron(Iii) And Six-Coordinate Cobalt(Iii) Complexes With Electroactive Phenol-Rich Ligands, Marco Mathieu Allard

Wayne State University Dissertations

Three 5 coordinate high-spin Iron(III) complexes containing pentadentate N2O5 ligands were synthesized and characterized, namely, (1) [FeIII(L1)] and (2) [FeIII(L2)]. Structural differences in ligand design,N,N,N'-tris(3,5-di-tert-butyl-2-hydroxybenzyl)benzene-1,2-diamine for (1) and N,N,N'-tris-(3,5-di-tert-butyl-2-hydroxybenzyl)-N'-methyl-benzene-1,2-diamine for (2), result in complexes that due to their forced geometry, asymmetry, and slightly different electronic structures are able to foster phenoxyl radicals although show a sensitive dependence to both the solvent and the electrolyte system in the cyclic voltammetry. In the presence of TBAClO4 (1) exhibits a two-electron oxidation, whereas in the presence of TBAPF6 (2), , shows three distinct phenolato/phenoxyl radical couples. Both (1) and (2) were redox-cycled 30 …

Synthetic Levers Enabling Control Of Phase, Size And Morphology In Transition Metal Phosphide Nanoparticles (Fe, Ni), Elayaraja Muthuswamy

Wayne State University Dissertations

ABSTRACT

SYNTHETIC LEVERS ENABLING CONTROL OF PHASE, SIZE AND MORPHOLOGY IN TRANSITION METAL PHOSPHIDE NANOPARTICLES (FE, NI)

by

ELAYARAJA MUTHUSWAMY

May 2011

Advisor:Dr. Stephanie L. Brock

Major: Chemistry

Degree: Doctor of Philosophy

This dissertation study focuses on (1) development of a synthetic strategy to control phase in nanoscale iron phosphides; (2) extension of the developed phase control strategy to the nanoscale nickel phosphide system with simultaneous control on size and morphology and (3) illustration of the enhanced reactivity of nanoscale oxide systems.

A synthetic strategy to control phase in nanoscale iron phosphides was developed to prepare phase-pure samples of …

Metal Chalcogenide Nanocrystal Assembly: From Synthesis To Applications, Qinghong Yao

Wayne State University Dissertations

This dissertation study is focused on (1) the application of an oxidation-induced sol-gel assembly method to formation of CdTe aerogels; (2) extension of existing aerogel compositions and properties by an alternative synthetic approach: cation-exchange reactions; and (3) probing the functionality of CdSe aerogels as optical sensors of Lewis base analytes.

Highly porous CdTe aerogels were successfully synthesized by sol-gel assembly of CdTe nanocrystals with thiolate or nonthiolate (phosphine oxide) ligated surfaces by treatment with tetranitromethane. Both phosphine oxide-capped and the thiolate-capped aerogels exhibit similar structure, morphology and porosimetry properties, suggesting that precursor ligation does not have a no major effect …

Synthesis And Characterization Of Metal Complexes Containing Tetrazolate, Poly(Tetrazolyl)Borate, And Aryl Pentazole Ligands As High Energy Density Materials, Dongmei Lu

Wayne State University Dissertations

Heavier alkaline earth metal tetrazolates have been prepared as cryatals contain aqua ligands and as anhydrous powders, and were characterized by spectral and analytical methods. Potassium bis(tetrazolyl)borate complexes K(BH₂(RCN₄)₂)(H₂O)_n (R = H, Me, NMe₂, and NiPr₂) and their 18-crown-6 adducts have been synthesized. In the solid state, complexes where R = H and Me have B-N bonds to the nitrogen atoms proximal to the carbon atom, whereas those with R = NMe₂ and NiPr₂ possess isomeric B-N bonds to the nitrogen atoms distal to the …

The Synthesis, Structure, And Properties Of Group 2 Poly(Pyrazolyl)Borates And Their Use For The Atomic Layer Deposition Of Group 2 Borates, Mark J. Saly

Wayne State University Dissertations

A series of heavy alkaline earth complexes containing TpR2-based ligands has been synthesized, structurally characterized, and their properties were investigated. Salt metathesis routes involving MI2 (M = Ca, Sr, Ba) with either KTpEt2 or KTpnPr2 afforded MTpEt22 or MTpnPr22 in good to moderate yields. All of these complexes are volatile and exceptionally thermally stable, and have acceptable properties for use as group 2 atomic layer deposition (ALD) precursors. In addition, a series of group 2 complexes containing BpR2-based ligand systems were synthesized. Treatment of MI2 (M = Ca, Sr, Ba) with two equivalents of TlBptBu2, KBp, and KBpiPr2 in tetrahydrofuran …