Organic Chemistry Commons^™

The Development Of An Effective Water-Soluble Receptor For Pyrene Derivative Dyes, Ashley Longstreet

Undergraduate Theses and Capstone Projects

A receptor with enhanced water solubility was synthesized from an existing receptor to be used as a pyranine fluorescence quencher in endovesiculation detection assays. The existing receptor consisted of a cyclen core with four protruding arms containing an aryl nitro group at each end. Its poor water solubility limited the accuracy and precision of the endovesiculation assay because the low concentration of receptor did not match the concentration of pyranine. To increase the water solubility, ethoxy groups were attached to the ends of each arm by first selectively reducing the nitro group to an amine with NaBHU4, H2, and a …

Relatin Dissolved Oxygen Concentration To Fish Distribution In Jarecki Lake, Adam Sutton

Department of Environmental Studies: Undergraduate Student Theses

Abstract Water temperature and dissolved oxygen (DO) profiles were measured once every month from mid July to mid February in a relatively deep sand-pit lake in southeast Nebraska. These profiles showed depleted DO concentrations below the thermocline during summer stratification indicating areas fish will likely avoid in summer months. Colder temperatures in fall caused complete mixing of the water column allowing fish to inhabit all depths of the lake. An inverse temperature stratification occurred directly below the ice during winter months as ice cover cooled the surface water to below 4 degrees Celsius. Ice cover also blocked air – water …

Herbicides And Amphibian Populations, Zach Shirk

Department of Environmental Studies: Undergraduate Student Theses

Amphibians are a unique class of species that are found worldwide except Antarctica and Greenland. They range in size from a few millimeters to over six feet long. Amphibian’s habitats are as various as their size, but one thing in common is that amphibians require an aquatic location to breed. Amphibians live in deserts, mountain prairies, rain forest, wetlands, and almost everywhere in between. Amphibians are an integrated part of most natural ecosystems across the world. Amphibians are a critical part of many food chains; they provide the important link between secondary and tertiary consumers. Amphibians are indicator species in …

Calculation Of Collisional Cross Sections For The ²P3/2 > ²P1/2 Transition In Alkali-Noble Gas Systems, Samuel D. Butler

Theses and Dissertations

Collisional cross sections were calculated as a function of energy for two coupled one dimensional, spherically symmetric potentials. The Split Operator Method was used to propagate an initial Moller state, chosen to be a Gaussian in the asymptotic limit, through a potential. The correlation between the wave packet and Moller final state was calculated at each time step. Using the Channel Packet Method, the correlation function was used to obtain scattering matrix elements. From scattering matrix elements for several different effective potential values and using the Method of Partial Waves, the collisional cross section is calculated for the transition from …

A Novel Choline Cotransporter Sequestration Compartment In Cholinergic Neurons Revealed By Selective Endosomal Ablation, Michael T. Ivy, Robert F. Newkirk, Yilun Wang, James G. Townsel

Biology Faculty Research

The sodium-dependent, high affinity choline transporter – choline cotransporter – (ChCoT, aka: cho-1, CHT1, CHT) undergoes constitutive and regulated trafficking between the plasma membrane and cytoplasmic compartments. The pathways and regulatory mechanisms of this trafficking are not well understood. We report herein studies involving selective endosomal ablation to further our understanding of the trafficking of the ChCoT. Selective ablation of early sorting and recycling endosomes resulted in a decrease of ∼75% of [3H]choline uptake and ∼70% of [3H]hemicholinium-3 binding. Western blot analysis showed that ablation produced a similar decrease in ChCoTs in the plasma membrane subcellular fraction. The time frame …

2,3-Bis(Bromomethyl)-1,4-Diphenylbenzene, Jonathan B. Briggs, Mikael D. Jazdzyk, Glen P. Miller

Chemistry

In the title compound, C(20)H(16)Br(2), the terminal phenyl groups are twisted away from the central ring by approximately 55 and -125 degrees (average of four dihedral angles each), respectively. The crystal structure is stabilized by a combination of interMolecular and intraMolecular interactions including interMolecular pi-pi stacking interactions [C atoms of closest contact = 3.423 ( 5) angstrom].

Novel Photochemical Methodologies For Diversity Oriented Synthesis And Screening Of Combinatorial Libraries, Roman Askatovich Valiulin

Electronic Theses and Dissertations

The main goal of this project was to develop an efficient methodology allowing rapid access to structurally diverse scaffolds decorated with various functional groups.

Initially, we discovered and subsequently developed an experimentally straightforward, high-yielding photoinduced conversion of readily accessible diverse starting materials into polycyclic aldehydes and their (hemi)acetals decorated by various pendants. The two step sequence, involving the Diels-Alder addition of heterocyclic chalcones and other benzoyl ethylenes to a variety of dienes, followed by the Paternò-Büchi reaction, was described as an alkene-carbonyl oxametathesis. This methodology offers a rapid increase in molecular complexity and diversity of the target scaffolds.

To develop …

Technology For The Organic Chemist: Three Exploratory Modules, John J. Esteb, Luanne M. Mcnulty, John Magers, Paul Morgan

Scholarship and Professional Work - LAS

The ability to use computer-based technology is an essential skill set for students majoring in chemistry. This exercise details the introduction of appropriate uses for this technology in the organic chemistry series. The incorporation of chemically appropriate online resources (module 1), scientific databases (module 2), and the use of a chemical drawing program (module 3) are detailed here.

Structure-Reactivity Relationships Of L-Proline Derived Spirolactams And A-Methyl Prolinamide Organocatalysts In The Asymmetric Michael Addition Reaction Of Aldehydes To Nitroolefins., Fintan Kelleher, Sinead Kelly, John Watts, Vickie Mckee

Articles

L-Proline derived spirolactams and a-methyl prolinamides act as organocatalysts for the asymmetric conjugate addition of aldehydes to nitroolefins in excellent yields, with good diastereoselectivity and enantioselectivity. Furthermore, low catalyst loadings (5 mol%) and a low aldehyde molar excess (1.5 molar equivalents) were achieved.

10,12-Dimethylpteridino[6,7-F][1,10]- Phenanthroline-11,13(10h,12h)-Dione– Chloroform (1/1), Waynie Olaprath, Jennifer Rodin, Kraig A. Wheeler, Mark E. Mcguire

Faculty Research and Creative Activity

In the title co-crystal, C18H12N6O2_CHCl3, intramolecular Cl3C—H_ _ _N hydrogen-bonding interactions occur between a single CHCl3 and both N atoms at the 1,10-positions on the phenanthroline portion of the molecule. The interplanar distance between inversion-related molecules is 3.241 (2) A ° .

Transition Metal-Mediated Higher-Order Cycloaddition Reactions: Application To The Total Synthesis Of Complex Natural Products, Bilal Abou Aleiwi

Wayne State University Dissertations

ABSTRACT

TRANSITION METAL-MEDIATED HIGHER-ORDER CYCLOADDITION REACTIONS: APPLICATION TO THE TOTAL SYNTHESIS OF COMPLEX NATURAL PRODUCTS

by

BILAL ABOU ALEIWI

October 2010

Advisor: Dr. James H. Rigby

Major: Chemistry (Organic)

Degree: Doctor of Philosophy

Chromium (0)-mediated [6ð + 2ð] and [6ð + 2ð + 2ð] cycloaddition reactions between cyclic trienes and alkynes is reported. The development, investigation and the application of these reactions in the total synthesis of complex ring systems and natural products is described. Two natural products, namely, ∆ 9(12) -Capnellene and Echinopines A and B were targeted.

An investigation led to the successful development of a methodology to …

Development And Applications Of Thioacids In Peptide Chemistry And Exploration Of Methods Toward The Stereochemical Elucidation And Synthesis Of Virgineone, Kasinath Sana

Wayne State University Dissertations

ABSTRACT

DEVELOPMENT AND APPLICATIONS OF THIOACIDS IN PEPTIDE CHEMISTRY AND EXPLORATION OF METHODS TOWARD THE STEREOCHEMICAL ELUCIDATION AND SYNTHESIS OF VIRGINEONE

by

KASINATH SANA

December 2010

Advisor: David Crich

Major: Chemistry

Degree: Doctor of Philosophy

This dissertation describes investigations toward the development of methods for the synthesis of peptidyl thioacids and thioesters, with particular emphasis on applications in peptide chemistry, and the exploration of methods toward the assignment of the relative and absolute configuration of virgineone and its total synthesis.

The first part of chapter one introduces the general characteristics and reactivity of thioacids, and describes their potential for application …

Dechalcogenative Allylic Selenosulfide And Disulfide Rearrangements For Cysteine Modification And Glycoligation, Venkataraman Subramanian

Wayne State University Dissertations

This thesis describes investigations directed at the development of methods for the selenosulfide and disulfide rearrangements for the permanent functionalization of thiols, and in particular of cysteine and carbohydrate based thiols. Emphasis is placed on the newly invented silver mediated allylic desulfurative rearrangement for the primary modification of thiols and the synthesis of complex oligosaccharide mimics.

Chapter one introduces the concept of chemoselective ligations for the modification of macromolecules like carbohydrates and proteins. It overviews the native and non-native ligation techniques for their modification of such entities with a attention focusing on thiol based ligation techniques. The later part of …

I. Microwave-Influenced Diversity-Oriented Synthesis Of Biologically Relevant Small & Natural-Product-Like Molecules Via Multicomponent Coupling Reactions Ii. Synthetic Studies Toward The Total Synthesis Of The Repeating Tetrasaccharide Unit Of Zwitterionic Polysaccharide Ps A1, Soumava Santra

Wayne State University Dissertations

Microwave-influenced diversity-oriented synthesis of biologically relevant small and natural-product-like molecules via multicomponent coupling reactions (MCCRs) have been investigated. Cheap, readily available starting materials in conjunction of microwave irradiation and employment of environmentally benign solvent (e.g. water) provided a common platform that allowed to access a wide array of structurally and skeletally diverse molecules. The investigation allowed us to establish a new paradigm of diversity-activity relationships (DARs) by tuning reacting components of the MCCRs and proved that in contrary to the conventional use of microwave as a rate accelerating tool, it can be used to influence reactivity of molecules. The method …

Analysis Of The Electron Withdrawing Capability Of Acetylene Groups For Promoting Nucleophilic Aromatic Substitution, Eric D. Braunstein

Honors Theses

It is well known that electron withdrawing groups, such as nitro or carbonyl groups, activate benzene rings for nucleophilic aromatic substitution. However, little research has been done to investigate the electron withdrawing capability of acetylene groups for substitution of aromatic halides. Experimental and computational investigations on the reactivity of halogenated phenylacetylenes with oxygen and other nucleophiles will be described.

Solid Supported Synthesis Of Secondary Amines Via Staudinger And Microwave Aza-Wittig Reactions, Kyle Thomas Holsinger

Undergraduate Honors Thesis Collection

Amine bond formation is a major topic in organic chemistry and is widely applied to the formation of medicinal compounds. Current studies have analyzed the benefits of microwave irradiation and solid supported reagents in order to improve reaction conditions and both synthetic and environmental costs. In the synthesis of amines, we investigate the combined use of microwave irradiation and solid supported reagents in the aza-Wittig and reductive amination reaction.

Synthesis Of Functionalized Gpi Anchors And Related Glycoconjugates, Benjamin M. Swarts

Wayne State University Dissertations

This dissertation is divided into two chapters describing the background, significance, and synthesis of GPI anchors and GPI-anchored molecules. GPI anchors are a class of complex glycolipids with the primary purpose of attaching cell surface proteins/glycoproteins to the cell membrane. The first chapter is focused on the synthesis of functionalized GPI anchors, and begins with an introductory look at the discovery, structure, biosynthesis, and biological functions of GPIs. Then, after surveying progress and achievements in GPI synthesis, including discussion about current strategic shortcomings in the field that prevent the chemical synthesis of various GPI derivatives, our approach to accessing uniquely …

Titanium Niobium Nano Porous Materials: New Photocatalysts For Water Decontamination, Maryam Zarei Chaleshtori

Open Access Theses & Dissertations

Water pollution is major environmental problem worldwide. Many common industrial organic compounds that make their way into water systems can be carcinogenic at trace levels and are difficult and costly to remove completely with conventional technologies. Because of this, authorities and researchers are trying to improve current water cleanup techniques.

Heterogeneous photocatalysts that accelerate the photocatalytic destruction of organic contaminants in water are a potentially inexpensive and highly effective way to remove both trace-level and saturated harmful compounds from industrial waste streams and drinking water. Titanium dioxide has the potential to completely mineralize organic compounds in water under ultraviolet light. …

An Improved Synthesis Of A Ring-C Precursor To Cobyric Acid, Hui Wang, Peter A. Jacobi

Dartmouth Scholarship

Alkyne acid 10 was prepared in enantioselective fashion from allylic ester derivative (R)-18 via an E-selective Ireland-Claisen rearrangement followed by Si-assisted elimination of HBr. The present route offers significant advantages in terms of both scalability and overall yield compared to that previously described. Alkyne acid 10 is an attractive ring-C precursor for an ongoing synthesis of cobyric acid.

Synthetic Studies On Angucycline C104, Rui Zheng

Legacy Theses & Dissertations (2009 - 2024)

The Hauser's annulation and Hauser and Xu's route for C-aryl glycoside synthesis were successfully employed to prepare the linear tetracyclic anthraquinone substituted C-aryl glycoside, galtamycin as well as bis C-aryl glycosides. Synthetic studies on angucycline C104 extended the utility of both methods to structures with angular tetracyclic framework.