Inorganic Chemistry Commons^™

Coordination Nature Of 4-Mercaptoaniline To Sn(Ii) Ion: Formation Of A One Dimensional Coordination Polymer And Its Decomposition To A Mono Nuclear Sn(Iv) Complex, Eon S. Burkett, Tasneem A. Siddiquee

Chemistry Faculty Research

The coordination of the bifunctional ligand 4-mercaptoaniline with aqueo us tin(II) metal ion was studied. A coordination polymer was synthesized when an aqueous solution of SnCl2 was treated with 4-MA. The crystalline material is stable under atmospheric conditions retaining its oxidation state. However, when submerged in a solution saturated with oxygen, the compound oxidizes to a mononuclear tin(IV) complex. Both the compounds were characterized by single crystal X-ray diffraction studies. Although the structure of the tin(IV) complex was previously reported, crystal structure of this compound was redetermined.

Association Of G-Quadruplex Forming Sequences With Human Mtdna Deletion Breakpoints, D. W. Dong, F. Pereira, Steven Paul Barrett , '13, J. E. Kolesar, K. Cao, J. Damas, Liliya A. Yatsunyk, F. B. Johnson, B. A. Kaufman

Chemistry & Biochemistry Faculty Works

Background: Mitochondrial DNA (mtDNA) deletions cause disease and accumulate during aging, yet our understanding of the molecular mechanisms underlying their formation remains rudimentary. Guanine-quadruplex (GQ) DNA structures are associated with nuclear DNA instability in cancer; recent evidence indicates they can also form in mitochondrial nucleic acids, suggesting that these non-B DNA structures could be associated with mtDNA deletions. Currently, the multiple types of GQ sequences and their association with human mtDNA stability are unknown. Results: Here, we show an association between human mtDNA deletion breakpoint locations (sites where DNA ends rejoin after deletion of a section) and sequences with G-quadruplex …

Physicochemical Characterization Of Novel 1,1 0-Phenanthrolines, Dominic Millheim

Masters Theses

1,10-Phenanthroline is a well-known and often-used ligand with a variety of interesting properties and applications to both organic and inorganic chemistry. Interest in novel 1,10-phenanthrolines substituted at the 5- and 6- position has grown recently due to their interesting fluorometric and spectroscopic properties. They have been evaluated recently for applications including chemical sensors, chemical indicators, pharmacological targets and bioactive reagents.

1,10-Phenanthroline, an epoxidated synthetic intermediate, and a novel 5,6- disubstituted aminoalcohol derivative were studied to determine the degree of influence that iterative physical and chemical transformations have on the donor properties of the N-C-C-N pocket. Multiple analytical techniques including potentiometry …

Molecular Probes For The Detection Of Zn2+ And Fe3+ Ions, Erendra Manandhar

Dissertations

A number of molecular probes have been designed and synthesized for the detection of Zn²⁺ and Fe³⁺ ions. Two types of functional groups have been incorporated into the molecular scaffolds to utilize different fluorescent mechanisms. The first class of receptors contains a pyrene moiety. These molecular probes use the excimer mechanism for the detection of Zn²⁺ ion. The probes work well in an organic solvent with a detection limit of 20 nM (one ppb). Alternatives are made to make them water soluble, but this proved to be difficult. An interesting ion-induced self-assembly system will also be discussed. …

Metallopeptides From Design To Catalysis: Structure, Oxidative Activities, And Inhibition Studies Of Designed And Naturally Occurring Metallopeptides, Alaa Hassan Hashim

USF Tampa Graduate Theses and Dissertations

Structural and mechanistic complexities of copper-dioxygen systems have attracted much attention in the field of bioinorganic chemistry, both in model systems and trapped protein intermediates. The research presented herein is focused on model and naturally occurring metallopeptide systems, from its design to catalysis. Copper is used as the coordinating metal ion, with cobalt and zinc as probes for metal binding. The bioinorganic chemistry of copper proteins and its coordination and spectroscopic properties are briefly discussed in chapter 1. The next two chapters are centered on the de novo design of a minimalistic metallopeptide system with an amino acid sequence of …

Synthesis And Formation Mechanism Of Cuins2 Nanocrystals With A Tunable Phase, Chao Yu, Linlin Zhang, Long Tian, Dan Liu, Fanglin Chen, Cheng Wang

Faculty Publications

Chalcopyrite CuInS₂ (CIS) hierarchical structures composed of nanoflakes with a thickness of about 5 nm were synthesized by a facial solvothermal method. The thermodynamically metastable wurtzite phase CIS would be obtained by using InCl₃ instead of In(NO₃)₃ as In precursor. The effects of the In precursor and the volume of concentrated HCl aqueous solution on the phases and morphologies of CIS nanocrystals have been systematically investigated. Experimental results indicated that the obtained phases of CIS nanocrystals were predominantly determined by precursor-induced intermediate products. The photocatalytic properties of chalcopyrite and wurtzite CIS in visible-light-driven degradation of …

Transformation Of Biomass Carbohydrates By Transition Metal Catalysts, Christine M Bohn

Open Access Dissertations

By selectively removing functional groups from biomass derived carbohydrates, valuable platform chemicals can be generated from renewable sources. Through dehydration chemistry glucose can be upgraded into 5-(Hydroxymethyl)-2-furfuraldehyde (HMF) and levulinic acid. Iron (III) chloride hexahydrate has shown moderate activity to transform glucose into HMF and has also shown high yields and selectivity for the production of levulinic acid. Typically synthesized from acidic solutions made with mineral acids, levulinic acid has now been produced in high yields with a metal salt. The difference between maximizing production for HMF or levulinic acid from the same catalyst relies on the control of the …

Mechanistic Studies Of Salt Effects On Bimolecular Electron-Transfer Reactions Of Pentaamine Ruthenium Pyridyl Complexes Studied By 19f Nmr Line-Broadening And T2 Spin-Echo Techniques, Nicholas J. Magarian

Master's Theses

Kinetic salt effects on the bimolecular ET self-exchange reaction between pentaamineruthenium(II)(3-trifluoromethylpyridine)²⁺, (NH₃)₅Ru^IItfmp²⁺, and pentaamineruthenium(III)(3-trifluoromethylpyridine)³⁺, (NH₃)₅Ru^IIItfmp³⁺, have been measured using both ¹⁹F NMR line-broadening and CPMG T₂ spin-echo relaxation techniques in H₂O and D₂O. Over the equimolar reactants concentration range of 0.10 mM – 8.00 mM there was a definite “self-salting” rate increase arising from the increased solution ionic strengths due to the reactants and counterions themselves. The magnitude of this effect diverged significantly, however, …

Water In The Computer Lab! (A Computational Project For Undergraduate Inorganic Chemistry), Bradley M. Wile, Trilisa M. Perrine

Chemistry and Biochemistry Faculty Scholarship

No abstract provided.

Self-Assembly Of Gold Nanosphere Dimers By Inertial Force, George Andrew Christopher Sakhel

Graduate Theses and Dissertations

The morphology and composition of a nanoparticle (NP) play a critical role in determining the NP's properties and function. To date, researchers have created a myriad of NPs of different shapes, sizes, and compositions with interesting attributes and applications ushering a revolution in medicine, electronics, microscopy, and microfluidics.

In this study, gold (Au) nanosphere dimers (NSDs) have been synthesized through a novel self-assembly method. These particles were created from Au NPs mono-dispersed in aqueous solution via a process of centrifugation and capping agent replacement. Au NSDs consist of two Au NPs combined together with minimal gaps between them. Optical spectral …

Heat Release Of Polyurethanes Containing Potential Flame Retardants Based On Boron And Phosphorus Chemistries, Vladimir Benin, Bastien Gardelle, Alexander Morgan

Chemistry Faculty Publications

Using a polyurethane of methylene diphenyl isocyanate and 1,3-propane diol, several new non-halogenated aromatic boron and phosphorus flame retardants were evaluated for heat release reduction potential using the pyrolysis combustion flow calorimeter (PCFC). The polyurethanes were prepared in the presence of the potential flame retardants via solvent mixing and copolymerization methods, and were then analyzed via spectroscopic methods to determine if the flame retardant was still present in the final product. PCFC testing on the resulting products showed that the flame retardant molecule can have different effects on heat release depending upon how it is mixed into the polyurethane. Some …

Density Functional Theory Modeling Of It-Stacking And Electrophilic Donor-Acceptor Interactions With Application To Therapeutic Targeting Of Zinc-Finger Proteins, Patricia Beall Lutz

Chemistry & Biochemistry Theses & Dissertations

Several viruses, including viruses that cause cancer, contain conserved zinc finger (ZF) proteins that are essential for viral reproduction, making them attractive drug targets for cancer and viral treatment. ZFs are small protein domains that have Zn²⁺ tetrahedrally coordinated to at least 2 Cys and His. They form three classes of ZFs depending on the amino acid ligands, CCHH, CCCH, and CCCC. Zn²⁺ is stable towards redox reactions; however, the Cys thiolates are redox active. Oxidation of the Cys thiolates release Zn²⁺, and the ZF loses its tertiary structure and can no longer bind DNA or …

Determination Of Corrosion Inhibitor Lubricity Improver In Jet Fuel By Liquid Chromatography-Electrospray Ionization Mass Spectrometry, David W. Johnson, Milissa Flake, Ryan Adams

Chemistry Faculty Publications

Military jet fuel (JP-8) is very similar to commercial jet fuel (Jet A) except for the presence of three additives, fuel system icing inhibitor, corrosion inhibitor–lubricity improver (CI-LI), and antistatic additive, which are added to improve characteristics of JP-8. Of particular interest is the CI-LI additive; the most common active ingredient is a dimer of linoleic acid. This article focuses on quantification of the active ingredient in the CI-LI additive by liquid chromatography–mass spectrometry (LC–MS). This method will allow the determination of CI-LI content in military jet fuel samples.

Synthesis, Characterization And Reactivity Studies Of Fe(Ii) Complexes With Relevance To The Radical Sam Enzymes, Xixi Hong

Master's Theses (2009 -)

It is well-established that S-adenosylmethionine (SAM) serves as the methyl group donor in methylations of DNA, hormones, neurotransmitters and signal transduction systems. However, a new class of enzymatic reactions involving SAM has recently attracted considerable attention. In these systems, SAM initiates radical-based reactions at the active sites of enzymes via formation of an adenosyl radical, which further abstracts a H-atom from the substrate to initiate a radical-based mechanism. However, modeling studies of radical SAM enzymes have been hindered, by difficulties in preparing adequate synthetic [Fe4S4] clusters. We prepared a novel series of Fe(II) complexes with tripodal tris(2-hydroxybenzyl)amine ligands, which replicate …

Synthesis And Dna-Binding Studies With Two Stericallyfriendly Porphyrin Frameworks, Srijana Ghimire

Open Access Dissertations

Peripheral substituents on cationic porphyrins play a significant role during binding with DNA hosts. Possible applications of these systems in photodynamic therapy as well as in anti-bacterial and anti-cancer therapies motivate the binding studies. For characterizing DNA binding motifs different methods are useful including absorption, emission, and circular dichroism spectroscopies, as well as viscometry and X-ray crystallography. With the classic H₂ T₄ porphyrin, or 5,10,15,20-tetra(N-methylpyridinium-4-yl)porphyrin, the mode of binding varies with the base composition of the DNA host. The porphyrin binds adenine-thymine rich sequences externally whereas intercalation occurs in guanine-cytosine rich sequences. The McMillin group has made some …

Synthesis, Characterization And Mechanistic Studies Of Biomolecules@Mesomofs, Yao Chen

USF Tampa Graduate Theses and Dissertations

Encapsulation of biomolecules is of great interest to research advances related to biology, physiology, immunology, and biochemistry, as well as industrial and biomedical applications such as drug delivery, biocatalysis, biofuel, food and cosmetics. Encapsulation provides functional characteristics that are not fulfilled by free biomolecules and stabilizes the fragile biomolecules. In terms of biocatalysis, solid support can often enhance the stability of enzymes, as well as facilitate separation and recovery for reuse while maintaining activity and selectivity. Various kinds of materials have been used for encapsulation of biomolecules, among which, porous materials are an important group. Metal-organic frameworks (MOFs) have attracted …

Metal-Organic Frameworks Based On Pyridyl-Tetrazole Ligands Containing Ester Or Carboxylate Pendant Arms, Ursula Sheridan, John Gallagher, Morten Bjerrum, Adrienne Fleming, Fintan Kelleher, John Mcginley

Articles

The coordination of pyridyl-tetrazole derivatives containing ester substituents, at either the N-1 or N-2 position of the tetrazole ring, with copper(II) chloride results in the formation of either 1:1 or 1:2 copper to ligand complexes, depending on the ligand. However, when the ester functionality is changed to a carboxylate group, the resulting complexation reactions yield metal-organic frameworks. The resulting structures vary dramatically in pore size, depending on both reaction solvents and position of carboxylate group on the tetrazole ring. Despite the presence of sodium cations in the reaction mixtures, no sodium incorporation was ever observed in any of the complexes. …

New Metal-Nhc Complexes: Synthesis, Characterization, And Uses, Roy A. Kelly Iii

LSU New Orleans Theses and Dissertations

N-Heterocyclic Carbenes (NHC) present a viable alternative to traditional phosphine ligands in a variety of organometallic mediated catalytic reactions. Singlet ground-state carbenes are stabilized by the push-pull presence of two adjacent nitrogen atoms in an imidizolium 5-membered ring, allowing neutral electron donor properties. The ability to synthesize a variety of NHC ligands with differing steric and electronic properties is possible by changing the sustiuents on the nitrogen atoms of the imidizolium. Tunable characteristics and enhanced chemical and thermal stability give NHC’s an advantage over phosphines in many catalytic systems.

This dissertation focuses on the use N-Hetercyclic Carbenes in a variety …

Comparative Studies On Standard And Fire-Rated Gypsum Wallboards., Harika Javangula

Masters Theses & Specialist Projects

The long term goal of this research is to improve the fire resistance of gypsum wallboard (GWB). Gypsum wallboard consists mainly of gypsum, i.e. calcium sulfate dihydrate, CaSO₄•2H₂O. In buildings, the chemical, mechanical and thermal properties of gypsum wallboard play an important role in delaying the spread of fire. To build a fire resistant GWB, it is very important to study the thermal, mechanical, physical and chemical properties of regular GWB and various types of fire-resistant wallboards available commercially in the market. Various fire-resistant GWBs have been compared and contrasted with reference to a standard wallboard …

Removal Of Arsenic Using Iron Coated Limestone, Anitha Swarna

Masters Theses & Specialist Projects

Arsenic contamination in drinking water is a severe problem worldwide. The best way to prevent hazardous diseases from chronic arsenic exposure is to remove the exposure. Efforts to remediate arsenic in drinking water have taken two tracks. One is to provide surface or shallow well water sources as an alternative to the arsenic contaminated deep wells. Another approach is to remove arsenic from the contaminated water. Different removal technologies like oxidation, chemical coagulation, precipitation, adsorption and others are available. There are problems and benefits associated with each of these approaches that can be related to cultural, socio-economic and engineering influences. …

Synthesis Of Perylenediimide-Functionalized Silsesquioxane Nanostructures, Lan Xu

Masters Theses & Specialist Projects

Organic semiconductors functionalized nanostructures are becoming as promising materials for electronic device applications including organic photovoltaics (OPVs). Perylenediimide (PDI) derivatives have also been known as one of the best n-type organic semiconductors. PDI derivatives can form bulk materials, which are both photochemically and thermally stable and have been widely used in various optoelectronic devices. Due to the formation of high electron mobility of crystalline domains, they prefer to incorporate into a silsesquioxane network. Here, we describe the potential applicability of perylenediimide functionalized silsesquioxane nanoribbons (PDI-dimethyl nanoribbons) as an acceptor for optoelectronic devices. We have developed synthetic procedures to make the …

Laboratory Scale Study Of Calcium Sulfate Hydration Forms, Sandeep Kumar Kuthadi

Masters Theses & Specialist Projects

This research is part of an ongoing project to create gypsum wallboards with enhanced fire resistance. The main goal of this research is to better understand the dehydration properties of calcium sulfate dihydrate, and the hydration of calcium sulfate hemihydrate as well as anhydrous calcium sulfate. The lab-scale kinetics of these processes were studied using thermogravimetric analysis and sorption analysis. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to characterize the products from different processes. In addition to the instrumental studies, small batches were handled in ovens and liquid slurries to better mimic the real world processing of …

Syntheses And Characterizations Of 4-Cyano-3-Tolylpyrazole And Its Metal Complexes, Molly M. Ketron

Undergraduate Honors Theses

Research on substituted polypyrazolylborate ligands could potentially lead to the development of useful compounds in the material sciences such as catalysis and metal ion extraction. A wide variety of substituents can be introduced to the pyrazole rings that modify the properties and reactivity of the complexes. Synthesis of 4-cyano-3-tolylpyrazole followed by the formation of a corresponding thallium(I) complex could allow one to examine the Tl-N bond length. When compared with other related complexes such as TlBp^{t-Bu, 4CN} and TlBp^{Ph, 4CN}, the Tl-N bond length in the synthesized complex will help determine the effect of the new …

The Analysis Of The Decomposition Of Hydrogen Peroxide Using A Schiff Base Copper Complex By Cyclic Voltammetry, Gavin James Rustin Mr.

Undergraduate Honors Theses

Copper(II) complexes of Schiff bases can be used in the catalysis of hydrogen peroxide to create water and oxygen. The mechanism and the kinetics of this disproportionation reaction by a dimeric copper(II) complex [CuSALAD]₂ are studied in this experiment, where SALAD refers to a Schiff Base ligand formed from salicyaldehyde and 1S,2S-D(+)-1-phenyl-2-amino-1,3-propanediol. By using cyclic voltammetry, the oxidation-reduction processes of a reaction may be monitored. The [CuSALAD]­₂ is initially reacted with a base such as imidazole to form the catalytic species, and the ratio of the copper(II) complex to the imidazole was found to be 1:4, consistent with …

Hydrothermal Synthesis Of Organically-Linked Polyoxometalates, Riyadh Alshammari

All Theses

One of the thrust areas of our research deals with exploratory synthesis of new inorganic-organic hybrid materials for energy storage. It is well-known that relevant to the research described later in this thesis, inorganic-organic hybrid solids studied thus far are largely made of coordination complexes where the organic molecules are acting like a ligand to coordinate around metal cations. In this research, we will employ polyoxometalate (POM) anions as an inorganic building block to replace otherwise oppositely charged metal cations in hopes to synthesize extended hybrid frameworks with rich redox chemistry. POM clusters are made of aggregates of transition-metal (TM) …

Template-Directed Synthesis And Post-Synthetic Modification Of Porphyrin-Encapsulating Metal-Organic Materials, Zhenjie Zhang

USF Tampa Graduate Theses and Dissertations

Metal-organic materials (MOMs) represent an emerging class of materials comprised of molecular building blocks (MBBs) linked by organic linker ligands. MOMs recently attract great attention because of their ability to exhibit permanent porosity, thereby enabling study of properties in the context of gas storage, gas separation, solid supports for sensors, catalysis and so on. Although MOMs have been studied for over 60 years, the porous nature of MOMs was not systematically and widely explored until the early 1990's. This may be one of the reasons why template-directed synthesis of MOMs remains relatively underexplored, especially when compared to other classes of …

Interfacial Rheology Of Bacterial Biofilms At Air/Water And Oil/Water Interfaces, Patrick Rühs, R. Inglis, Peter Fischer

Biology Department Faculty Works

No abstract provided.

N-Methylmesoporphyrin Ix Fluorescence As A Reporter Of Strand Orientation In Guanine Quadruplexes, Navin C. Sabharwal , '14, V. Savikhin, Joshua R. Turek-Herman , '16, John Michael Nicoludis , '12, V. A. Szalai, Liliya A. Yatsunyk

Chemistry & Biochemistry Faculty Works

Guanine quadruplexes (GQ) are four-stranded DNA structures formed by guanine-rich DNA sequences. The formation of GQs inhibits cancer cell growth, although the detection of GQs invivo has proven difficult, in part because of their structural diversity. The development of GQ-selective fluorescent reporters would enhance our ability to quantify the number and location of GQs, ultimately advancing biological studies of quadruplex relevance and function. N-methylmesoporphyrin IX (NMM) interacts selectively with parallel-stranded GQs; in addition, its fluorescence is sensitive to the presence of DNA, making this ligand a possible candidate for a quadruplex probe. In the present study, we investigated the effect …

Thioflavin T As A Fluorescence Light-Up Probe For G4 Formation, A. R. De La Faverie, A. Guédin, A. Bedrat, Liliya A. Yatsunyk, J.-L. Mergny

Chemistry & Biochemistry Faculty Works

Thioflavin T (ThT) becomes fluorescent in the presence of the G-quadruplex structure such as that formed by the human telomeric motif. In this report, we extend and generalize these observations and show that this dye may be used as a convenient and specific quadruplex probe. In the presence of most, but not all, G4-forming sequences, we observed a large increase in ThT fluorescence emission, whereas the presence of control duplexes and single strands had a more limited effect on emission. This differential behavior allowed us to design a high-throughput assay to detect G4 formation. Hundreds of different oligonucleotides may be …

The Development Of 6.7% Efficient Copper Zinc Indium Selenide Devices From Copper Zinc Indium Sulfide Nanocrystal Inks, Brian Kemp Graeser

Open Access Theses

As solar cell absorber materials, alloys of CuIn(S,Se)2 and Zn(S,Se) provide an opportunity to reduce the usage of indium along with the ability to tune the band gap. Here we report successful synthesis of alloyed (CuInS2 )0.5(ZnS)0.5 nanocrystals by a method that solely uses oleylamine as the liquid medium for synthesis. The reactive sintering of a thin film of these nanocrystals via selenization at 500 °C results in a uniform composition alloy (CuIn(S,Se)2 )0.5 (Zn(S,Se)) 0.5 layer with micron size grains. Due to the large amount of zinc in the film, the sintered grains exhibit the zinc blende structure instead …