Physical Sciences and Mathematics Commons^™

Exchange Mechanisms In Macroscopic Ordered Organic Magnetic Semiconductors, Naveen Rawat

Graduate College Dissertations and Theses

Small molecule organic semiconductors such as phthalocyanines and their derivatives represent a very interesting alternative to inorganic semiconductor materials for the development of flexible electronic devices such as organic thin field effect transistors, organic Light Emitting Diodes and photo-voltaic cells. Phthalocyanine molecules can easily accommodate a variety of metal atoms as well in the central core of the molecule, resulting in wide range of magnetic properties. Exploration of optical properties of organic crystalline semiconductors thin films is challenging due to sub-micron grain sizes and the presence of numerous structural defects, disorder and grain boundaries. However, this can be overcome by …

Investigation Of A Ring Fragmentation Reaction For The Synthesis Of Tethered Aldehyde Ynones And Medium Sized Cyclic Ynones And Ynolides, Ali Bayir

Graduate College Dissertations and Theses

The fragmentation of γ-silyloxy-β-hydroxy-α-diazoesters to provide tethered aldehyde ynoates was discovered and developed in Prof. Brewer's laboratory. This reaction is a Lewis acid mediated heterolytic cleavage of the Cβ-γ bond of a γ-silyloxy-β-hydroxy-α-diazocarbonyl functional group array contained in a ring compound.

This dissertation describes a further study of this ring fragmentation reaction and application of this fragmentation to the preparation of synthetically useful organic molecules. The purpose of this dissertation work was three fold. The first objective was to extend this ring fragmentation reaction to the synthesis of tethered aldehyde ynones by fragmenting various γ-silyloxy-β-hydroxy-α-diazo ketone compounds. The second objective …

Burst Pressure Properties And Ex Vivo Analysis Of Alginate-Based Hydrogels For Tissue Sealant Applications, Patrick Nelson Charron

Graduate College Dissertations and Theses

Lung diseases, cancers, and trauma can result in injury to the connective tissue lining the lung, i.e., the pleura. Pleural injuries lead to pneumothoraxes or pleural effusions, i.e., air or fluid leaking out of the lung respectively, and potential lung collapse - an immediately life threatening condition. While several bioengineered soft tissue sealants exist on the market, there is only one sealant FDA-approved for use in pulmonary surgery. In addition, very limited techniques are presented in the literature for characterizing the burst properties of hydrogel tissue sealants. For my thesis, I proposed to develop a protocol for characterizing the burst …

Studies Toward The Total Synthesis Of Subincanadine E, Corinne Marie Sadlowski

Graduate College Dissertations and Theses

Progress towards a concise total synthesis of subincanadine E is reported. This natural product was first isolated from the Picralima nitida cell suspension culture line in 1982 under the name pericine and later in 2002 from Aspidosperma subincanum as subincanadine E. It is the most potent compound of its class with in vitro cytotoxicity against both murine lymphoma L1210 and human epidermoid carcinoma KB cells (LD50, 0.3 ug/mL and 4.4 ug/mL, respectively) and was found to be six times more potent than codeine as an opiate agonist in a 3H-naloxone binding study (IC50, 0.6 umol/L).

The first-generation synthesis produced an …

I. A New Route To Azomethine Ylides: Shifting The Reliance On Amino Ester Precursors Ii. Applications In Total Synthesis, Natalie Kay Machamer

Graduate College Dissertations and Theses

Nitrogen-containing heterocycles have great utility in the biomedical and medicinal fields and one such heterocycle is the 5-membered pyrrolidine ring. The synthesis of pyrrolidine rings has been studied extensively with the routes relying on anodic oxidation, transition metals and dipolar cycloadditions with azomethine ylides. Previous work in the Waters group has been focused on new routes to azomethine ylides through a domino sequence. Through a thermal aza-Cope rearrangement followed by [3+2] dipolar cycloaddition the synthesis of a library of 2-allyl pyrrolidines was accomplished. It was discovered that by using allylic amines and glyoxals at room temperature a cycloadduct was isolated …

A Comparative Examination Of The Safety Programs At Ucla, Umn, And Uvm In Response To Recent Chemistry Laboratory Incidents, Victoria Carhart

Graduate College Dissertations and Theses

Laboratory safety has recently become more of an imperative in research laboratories than it has ever been in the past. Recent accidents at several universities have escalated the awareness of safety concerns in laboratory workspaces among the general public and created a greater need for a stronger culture of safety in chemistry research overall. Historically, results and publications have been the top priority of most researchers, not laboratory safety.

This thesis discusses a number of laboratory accidents. The first happened in December of 2008 at the University of California, Los Angeles (UCLA) and resulted in the death of a graduate …

Catalytic Main Group Element Bond Formation Reactions Toward The Preparation Of Conjugated Materials, Neil Mucha

Graduate College Dissertations and Theses

Polymers incorporating main group elements offer different and interesting properties compared to their all carbon analogues. For example, π-conjugated polymers incorporating phosphorus in the main chain of the polymer have generated interest due to their unique thermal and electronic properties, which primarily result from delocalization of the phosphorous lone pair within aromatic units. Similarly, interest in polysilanes stems from conductivity resulting from σ electron delocalization, though current methods of preparation for both of these types of materials are lacking. In this dissertation, both early and late transition-metal compounds were used to dehydrocouple phosphine and silane substrates. The use of dehydrocoupling …