Inorganic Chemistry Commons^™

Synthesis And Characterization Of Iron(Ii) Complexes Modeling The Active Site Structure Of Nonheme Iron Dioxygenases, Jacob Baus

Master's Theses (2009 -)

The aerobic degradation of polycyclic aromatic compounds, which are widespread contaminants in soils and groundwaters, is carried-out in large part by various Fe-containing dioxygenases that perform the cis-dihydroxylation and oxidative cleavage of aromatic rings. Recently, a new Fe dioxygenase family emerged that catalyzes a remarkable set of transformations; the distinguishing feature of these enzymes is that their monoiron(II) centers are coordinated by three histidines residues (i.e., imidazole ligands) in a facial geometry - a departure from the "canonical" 2-histidine-1-carboxylate facial triad that is dominant among nonheme monoiron enzymes. Members of the "3His family" are capable of oxidatively cleaving C-C bonds …

Investigation And Synthesis Of Novel Graphene-Based Nanocomposites For Hydrogen Storage, Anthony Joseph D'Angelo

USF Tampa Graduate Theses and Dissertations

It is of great interest to develop and utilize a high surface area material with optimized hydrogen sorption properties. The need for a renewable energy source to replace automobile gasoline has become more critical in the past decade. Hydrogen is a viable fuel source for automobile usage; however, the question of how hydrogen will be safely and efficiently stored still remains. Critical factors for optimum hydrogen storage include ambient conditions and low activation temperature for adsorption and desorption phenomena. In order for optimum hydrogen adsorption to be achieved, the properties of (1) high surface area, (2) optimum hydrogen adsorption energy, …

Synthesis, Characterization And Computational Study Of [4]Octamethylferrocenophane, Benjamin Mark Wilson

Theses, Dissertations and Capstones

This thesis reports the synthesis of an organic molecule, 1,4-bis(2,3,4,5-tetramethylcyclopentadienyl)butane by two different methods, in about 75% and 85% crude yield. Deprotonation of this molecule followed by reaction with FeCl2 generated the tethered ferrocene, [4]octamethylferrocenophane. Although the yield was low in the first attempt (2%), this molecule has been characterized through NMR spectroscopy, X-ray crystallography, electronic spectroscopy, elemental analysis, and decomposition temperature. A computational study was performed to determine the energy gap between each minimum energy structure. It was found that the energy barrier was not high enough to prevent a rapid interconversion between the two structures of minimum energy …

Transmetallation Of A Lithium Porphyrin With Iron(Ii), Kidus Debesai

The Corinthian

Synthesis and characterization of the iron(III) derivative of the 2,3,7,8,12,13,17,18-octabromo-meso-tetrakis(N-methylpyridium-4-yl)porphyrin was accomplished via metal metathesis of the lithium porphyrin and iron(II) ion. Preliminary molecular orbital analysis of the iron(II) and iron(III) derivatives demonstrate that the iron(III) porphyrin exists at a lower energy state.

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 …

Functionalized Ruthenatricarbadecaborane Via Selective Cage Iodination And Sonogashira Coupling Reactions, Ariane Perez-Gavilan, Larry Sneddon, Patrick J. Carroll

Articles

Selective iodination of the cyclopentadienylruthenium tricarbadecaboranyl complexes 1-(η5-C5H5)–2-Ph–closo-1,2,3,4-RuC3B7H9 (1) and 1-(η5-C5(CH3)5)–2-Ph–closo-1,2,3,4-RuC3B7H8 (2) to form their mono-iodo derivatives, 1-(η5-C5H5)–2-Ph–6-I–closo-1,2,3,4-RuC3B7H9 (3) and 1-(η5-C5(CH3)5)–2-Ph–6-I–closo-1,2,3,4-RuC3B7H8(4), was achieved in 90% yields by their reactions with ICl in CH2Cl2 solutions. Also isolated in trace amounts from the reaction with 2 was the di-iodo 1-(η5-C5(CH3)5)–2-Ph–6,11-I2–closo-1,2,3,4-RuC3B7H7, (5) complex. The sonication-promoted Sonogashira coupling reaction of 3 with terminal acetylenes catalyzed by Pd(dppf)Cl2/CuI yielded the functionalized ruthenatricarbadecaboranyl complexes 1-(η5-C5H5)–2-Ph–6-(Ph-C≡C)–closo-1,2,3,4-RuC3B7H8 (6), 1-(η5-C5H5)–2-Ph–6-[CH3CH2C(O)OCH2-C≡C]–closo-1,2,3,4-RuC3B7H8 (7), …

Synthesis And Flame Retardant Testing Of New Boronated And Phosphonated Aromatic Compounds, Vladimir Benin, Sravanthi Durganala, Alexander Morgan

Chemistry Faculty Publications

The present report describes the preparation and use of some dimethyl terephthalate derivatives in transition metal-catalyzed coupling reactions to produce new reactive flame retardants. Dimethyl iodoterephthalate and dimethyl 2,5-diiodoterephthalate were successfully employed in the preparation of phosphonic and boronic esters and acids. The latter were tested for heat release with a microcombustion calorimeter (ASTM D7309) to determine the potential for heat release reduction of these flame retardant molecules. The results showed that the addition of boronic or phosphonic acids greatly lowered the heat release, due to a condensed phase (char formation) mechanism. Adding ester groups to the boronic acids or …

Quantitative Analysis Of Some Important Metals And Metalloids In Tobacco Products By Inductively Coupled Plasma-Mass Spectrometry (Icp-Ms), Syed Ghulam Musharraf, Muhammad Shoaib, Amna Jabbar Siddiqui, Muhammad Najam-Ul-Haq, Aftab Ahmed

Pharmacy Faculty Articles and Research

Background: Large scale usage of tobacco causes a lot of health troubles in human. Various formulations of tobacco are extensively used by the people particularly in developing world. Besides several toxic tobacco constituents some metals and metalloids are also believed to pose health risks. This paper describes inductively coupled plasma-mass spectrometric (ICP-MS) quantification of some important metals and metalloids in various brands of smoked, sniffed, dipped and chewed tobacco products.

Results: A microwave-assisted digestion method was used for sample preparation. The method was validated by analyzing a certified reference material. Percentage relative standard deviation (% R.S.D.) between recovered …

Progress Towards A Facile Synthesis Of A Gadolinium (Iii) Octabrominated Porphyrin, Tseng Xiong

The Corinthian

Towards preparing porphyrin complexes that combine contrast agent and photodynamic therapy capabilities at tumor sites, the Gd(III) porphyrin derivative of the octabrominated meso-tetrakis(N-methyl-4-pyridyl)porphyrin, GdTMPyPBr8 5+ was synthesized by refluxing Gd(III) ion with H3TMPyPBr8 5+ at pH 7. The metallocomplex was characterized by UV-visible spectroscopy and showed a Soret band shift from 503 nm to 463 nm at pH 7, suggesting that metal insertion of Gd(III) into the core of porphyrin ligand had occurred. However, synthesis of the Gd(III) complex required high temperatures and long reaction times. To circumvent these harsh conditions, the lithium porphyrin derivative was first prepared and subsequently …

Tunable Gold Nanostructures With Nanocapsules As Template Reaction Vessels, Balasubramanian Ramjee, Srujana Prayakarao, Sangbum Han, Wei Cao

Chemistry & Biochemistry Faculty Publications

Hollow, polymeric, thiol-ene resorcinarene nanocapsules can act as template reaction vessels for the synthesis of gold nanoshells or spherical aggregates of gold nanoparticles depending on the reaction conditions. The spherical nanoparticle aggregates were evaluated as catalysts in the biphasic reduction of 4-nitrophenol.

Metal Catalyzed Activation Of E-H Bonds, E = Si, Ge, Sn, Renzo Nelson Arias Ugarte

Open Access Theses & Dissertations

The present project covers the use of complexes of the type: (C5H5)M(CO)nLMe, (M = Fe, n = 1; L = CO, Ph3P; M = Mo, n = 2; L = CO, Ph3P); M(CO)6, (M = Cr, Mo, W) and M(CO)5NMe3 as catalysts for the activation of E-H bonds (E = Si, Ge and Sn). The work is divided in three sections; the first two involves dehydrogenation and the last one amide reduction.

Magnetic And Orbital Orders Coupled To Negative Thermal Expansion In Mott Insulators, Ca2ru1-Xmxo4 (M = 3d Transition Metal Ion), Tongfei Qi

Theses and Dissertations--Physics and Astronomy

Ca₂RuO₄ is a structurally-driven Mott insulator with a metal-insulator (MI) transition at T_MI = 357K, followed by a well-separated antiferromagnetic order at T_N = 110 K. Slightly substituting Ru with a 3d transition metal ion M effectively shifts T_MI and induces exotic magnetic behavior below T_N. Moreover, M doping for Ru produces negative thermal expansion in Ca₂Ru_1-xM_xO₄ (M = Cr, Mn, Fe or Cu); the lattice volume expands on cooling with a total volume expansion ratio reaching as high as 1%. The onset of the …

Relating Dynamic Protein Interactions Of Metallochaperones With Metal Transfer At The Single-Molecule Level, J. J. Benítez, A. M. Keller, D. L. Huffman, Liliya A. Yatsunyk, A. C. Rosenzweig, P. Chen

Chemistry & Biochemistry Faculty Works

Metallochaperones undertake specific interactions with their target proteins to deliver metal ions inside cells. Understanding how these protein interactions are coupled with the underlying metal transfer process is important, but challenging because they are weak and dynamic. Here we use a nanovesicle trapping scheme to enable single-molecule FRET measurements of the weak, dynamic interactions between the copper chaperone Hahl and the fourth metal binding domain (MBD4) of WDP. By monitoring the behaviors of single interacting pairs, we visualize their interactions in real time in both the absence and the presence of various equivalents of Cu(1+). Regardless of the proteins' metallation …

Synthesis Of An Antimicrobial Textile Coating, William M. Morris

Chemistry and Biochemistry

A titania nanosol was synthesized and coated onto nylon/cotton blended textile substrates. The substrates were characterized via SEM for adhesion and nanoparticle formation, then subjected to antimicrobial efficacy tests. The titania nanosol was successfully coated on to textiles samples. Particles were observed to be around 2 by 3 micrometers and formed between the interstitial space of textile fibers. Although larger than typical nanoparticles, the coatings exhibited what seemed to be antimicrobial activity. Titania nanosol coated textile samples were subjected to Kirby Bauer Assay in the presence of S. aureus. The coated textile sample exhibited an inhibition of growth around its …

The Tetrafluoroborate Salt Of 4-Methoxybenzyl N-2-(Dimethylamino)Ethyl-N-Nitrosocarbamate: Synthesis, Crystal Structure And Dft Calculations, Helene Hedian, Vladimir Benin

Chemistry Faculty Publications

The tetrafluoroborate salt of 4-methoxybenzyl N-2-(dimethylamino)ethyl-N-nitrosocarbamate was prepared in two steps, via the corresponding carbamate. Its crystal structure is monoclinic, space group P21/c. The unit cell dimensions are: a = 19.499(8) Å, b = 5.877(3) Å, c = 15.757(7) Å, α = 90°, β = 110.019(7)°, γ = 90°, V = 1696.5(12) Å3, Z = 4. The structure exhibits an unexpected, pseudo-gauche conformation with respect to the C2–C3 bond, due to a stabilizing hydrogen bond between the carbonyl oxygen (O1) and the hydrogen atom at the trialkylammonium center (H3n), with a distance between them of …

Electrochemistry Of Pani/Metal Composites In Basic Solutions, Tamthinhan Quy

UNLV Theses, Dissertations, Professional Papers, and Capstones

Polyaniline (PANI) has been extensively investigated due to its unique conductivity, which is primarily dependent on the oxidation state of the material and the solution pH. PANI is an insulator when it is oxidized, and the solution pH exceeds four. Numerous attempts to extend PANI's conductivity to neutral and alkaline environments have been unsuccessful. However, our previous study has demonstrated that PANI/Pd composite is conductive and catalytically active in a basic solution, pH ∼ 12. Therefore, the conductivity and the electrochemical properties of PANI composites including PANI/Au, PANI/Pd and PANI/Pt were evaluated in basic solutions. The fundamental studies of PANI/metal …

Sweep, Step, Pulse, And Frequency-Based Techniques Applied To Protein Monolayer Electrochemistry At Nanoparticle Interfaces, Debbie S. Campbell-Rance, Tran T. Doan, Michael C. Leopold

Chemistry Faculty Publications

Protein monolayer electrochemistry (PME), a strategy using synthetic platforms to study the electron transfer (ET) properties of adsorbed proteins, has been successfully applied to proteins adsorbed at monolayer-protected gold cluster (MPCs) assembled films, an adsorption interface shown to be an effective alternative, compared to traditional self-assembled monolayer (SAM) films, for the immobilization and study of ET proteins. Within PME studies, cyclic voltammetry (CV) remains the most commonly applied electrochemical technique in spite of several limitations that occur when the sweep technique is used at either platform. In particular, CV for PME at MPC films results in analysis complications stemming from …

Computational Studies Of Ion Transport In Polymer Electrolytes, Hui Wu

Doctoral Dissertations

Improving ionic conductivity and lithium mobility in polymer electrolytes is important for their practical use for battery electrolytes. In this study, a combination of molecular dynamics and Monte Carlo simulations was used to bring insight into lithium ion transport in poly(ethylene oxide) (PEO) with plasticizers and also next to alumina solid surface doped with lithium salt. The simulations were performed using a moderately high molecular weight polymer (Mn = 10,000 g/mol) at an EO:Li ratio of 15. For the plasticized system, the PEO with LiN(CF3SO 2)2 (LiTFSI) was mixed with 10 wt% plasticizers that included either cyclic ethylene carbonate …