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Synthesis Of Adjacent-Bridged Benzo-Annelated Cyclam And Studies Of Mono- And Di-Benzo-Annelated Cyclam Derivatives, Amanuel B. Ghidey

Master's Theses and Capstones

A new synthetic methodology for the preparation of a novel adjacent-bridged benzoannelated cyclam is presented. This methodology utilizes reductive ring expansion followed by deallylation to give the desired adjacent-bridged benzo-annelated cyclam. This novel ligand is designed to complex metal cations with a trans coordination geometry. Derivatives of this ligand can be prepared by attaching pendant arms on the nitrogens which can aid as coordinating arms and linkers for potential use of this ligand as bifunctional chelator (BFC).

Coupling chemistry studies have been carried out in an attempt to increase the lipophilicity of a dibenzo-annelated tetracyclic bisaminal and to functionalize at …

Theoretical Analysis Of The Reaction Of Peroxymethyl Radical With Atomic Hydrogen And Of Dibenzofuran With Atomic Chlorine, Mikhail Zhukovskiy

Master's Theses and Capstones

Experimental determination of rate constants for gas phase radical reactions is challenging. When rate constants necessary for modeling complex processes in atmospheric and combustion science are unknown, theoretical predictions are useful. We used Variational Transition State Theory with Multidimensional Tunneling (VTST/MT) with Density Functional Theory (DFT) to calculate the rate constant and isotope effects for reaction between the peroxymethyl radical and the hydrogen atom.

Polychlorinated dibenzofurans (PCDFs) are a group of extremely toxic compounds formed during waste incineration. Currently, their chemical degradation in the atmosphere is poorly understood. While some experimental and theoretical results regarding the reaction of PCDFs with …

Spectroscopic Investigations Of The Photochemical Properties Of I. Spiropyran On Y Zeolite For Photochromic Applications Ii. Rhenium(I) Bipyridyl Tricarbonyl On Mesoporous Zsm-5 Zeolite And Silica For Photocatalytic Reduction Of Carbon Dioxide, Kevin Dubois

Master's Theses and Capstones

Immobilization of photoactive molecules on porous and nano-sized solid supports provides unique interactions which affect photophysical properties. In situ diffuse reflectance FTIR and UV-vis spectroscopies were primarily used to investigate the properties of surface functionalized materials. Spectroscopic characterization of photochromic spiropyran molecules physically adsorbed on Y zeolite revealed the importance of surface water in controlling kinetics and reversibility of photoswitching by stabilizing the merocyanine isomer. Re(bpy)(CO)3C1 was both physically adsorbed on a mesoporous ZSM-5 zeolite and covalently bound via the bipyridyl ligand on fumed silica to generate photocatalytic CO2 reduction materials. Upon light irradiation of the solids in the presence …

Novel Synthesis Of Sulfur Based Ligands Used In Modeling Biological Hydrogen Bonding Interactions, Tyler Jesse Jacinto

Master's Theses and Capstones

Heme-thiolate proteins are known to have hydrogen bond donors proximal to the axial thiolate ligand. The specific roles of these conserved H-bond donors have not yet been elucidated. However, various sources agree upon the positive influence that increased X-H···S interactions have on protein redox potentials. For example, synthetic modeling studies of the cytochromes P450 show similar positive shifts in potential in iron-porphyrin-thiolate model systems. The ligands used in modeling the H-bonding interactions in the P450 cytochromes included a series of 2,6-substituted thiophenols, -S(2,6-(CX3CONH)2C6H3), where X = H, F, CH3. The current synthetic route to these ligands is vague and employs …

Covalent Attachment Of A Diimine Tricarbonyl Re(I) Catalyst On Solid State Nano-Material Surfaces For Solar Carbon Dioxide Reduction, He He

Master's Theses and Capstones

Reduction of carbon dioxide to useful chemicals and fuels is of significant interest. Transition metal complexes, such as tricarbonyl rhenium(I) compounds, are efficient molecular catalysts for photocatalytic carbon dioxide reduction. To improve the stability and catalytic activity of homogeneous catalysts, a mesoporous silica material, SBA-15, was synthesized and applied as catalyst support for immobilizing the tricarbonyl rhenium(I) compound via both covalent bonding and physical adsorption. The covalently bonded tricarbonyl rhenium(I) catalyst in SBA-15 exhibited excellent stability and good activity during the photocatalytic reduction process, compared with its homogeneous counterpart and the physically absorbed one. Another solid-state nano-material, Kaolin, was also …