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Articles 61 - 90 of 2534
Full-Text Articles in Organic Chemistry
Modular Synthesis Of Conjugated Aromatic Systems Via Palladium-Catalyzed Cross-Coupling Reactions, Joden Russell Robinson
Modular Synthesis Of Conjugated Aromatic Systems Via Palladium-Catalyzed Cross-Coupling Reactions, Joden Russell Robinson
Dissertations, Master's Theses and Master's Reports
This thesis describes the development of a modular synthetic route to extended conjugated aromatic systems through iterative palladium-catalyzed Sonogashira crosscoupling reactions. The work was motivated by the challenge of preparing a discrete conjugated molecule in a controlled manner. The synthetic strategy used complementary protected alkyne functionalities that could be selectively activated. This enabled sequential deprotection and coupling reactions to predictably extend the molecular scaffold. Using this approach, a series of conjugated intermediates was prepared and exponentially extended. Spectroscopic characterization by NMR and mass spectrometry supported the structures of the isolated products and the success of the iterative elongation strategy. Overall, …
Synthesis And Characterization Of Succinate Dehydrogenase Inhibitors H2/Z14 And C6/Z96 In Order To Combat Small Cell Lung Cancer, Lauren M. Graves
Synthesis And Characterization Of Succinate Dehydrogenase Inhibitors H2/Z14 And C6/Z96 In Order To Combat Small Cell Lung Cancer, Lauren M. Graves
Honors Undergraduate Theses
The use of ubiquinone inhibitors to combat cancer is a recent development in medicinal science and procedures to efficiently synthesize these drugs remain limited. C6/Z96 and H2/Z14, two succinate dehydrogenase inhibitors, have been previously tested in vitro against NSCLC with positive results. Their similarity to ubiquinone is what makes them a strong candidate for a succinate dehydrogenase inhibitor at the ubiquinone binding site. The heterocyclic scaffolds and substituents are proposed to bind strongly through a combination of electronics, hydrogen-bonding, and fit, allowing them to bind well and prove to be more favorable than ubiquinone when competing for the Q-site. By …
Sulfhydryl-Functionalized Diarylethenes: Synthesis, Photoswitching, And Fluorescent Properties, Pramod Aryal, Jonathan Bietsch, Gowri Sankar Grandhi, Josh Choi, Guijun Wang
Sulfhydryl-Functionalized Diarylethenes: Synthesis, Photoswitching, And Fluorescent Properties, Pramod Aryal, Jonathan Bietsch, Gowri Sankar Grandhi, Josh Choi, Guijun Wang
Chemistry & Biochemistry Faculty Publications
Sulfhydryl group (SH) plays important roles in reactions with various functional groups, especially in biologically active systems. Photoswitchable diarylethene (DAE) derivatives have demonstrated applications in many research fields. Among the many classes of diarylethene derivatives, thiol derivatives have not been extensively explored. In this study, we systematically synthesized and characterized a series of bis-thiol functionalized dithienylethene derivatives. The thiol groups in this series are attached directly to the thiophene, or through a phenyl or methylene linker. Each series incorporated both dithienyl cyclopentene and hexafluorocyclopentene bridges and total six thiol substituted diarylethenes were synthesized. Among the six sulfhydryl DAE derivatives, four …
Comprehensive Analytical Investigation Of Tetrahydro-4h-Chromene And Dihydropyridine Derivatives, Ryan J. Burk
Comprehensive Analytical Investigation Of Tetrahydro-4h-Chromene And Dihydropyridine Derivatives, Ryan J. Burk
Chemistry & Biochemistry Dissertations
Novel calcium channel blockers (CCBs) with dihydropyridine (DHP) or tetrahydro-4H-chromene moieties are often chiral, so effective enantiomer separation methods are needed for continued drug development. The purpose of this dissertation is to outline a comprehensive method development model for the chiral separations of DHPs and tetrahydro-4H-chromene derivatives. The scope of this dissertation is to address analytical challenges during initial synthesis, chiral separations, and data analysis during post-processing for this class of chiral compounds. The first section focuses on the method development strategies for separations of DHPs in the sub/supercritical fluid (SFC) and normal phase modes with the 2-hydroxypropyl-β-cyclodextrin stationary phase. …
An Investigation Into The Potential Role Of Thioester Bonds In Prebiotic Atp Synthesis, Adam J. Ruf
An Investigation Into The Potential Role Of Thioester Bonds In Prebiotic Atp Synthesis, Adam J. Ruf
Williams Honors College, Honors Research Projects
In this project I will attempt to show a potential prebiotic pathway for the synthesis of ATP. This pathway involves the use of thioester bond containing molecules, as derivatives of these bonds have been shown to exhibit enzyme-like catalytic properties. Nuclear magnetic resonance spectroscopy will be utilized to characterize each step of the pathway to ensure it is successful.
Corannulene: Optimized Synthesis And Four-Fold Reduction, Guy Rozenman
Corannulene: Optimized Synthesis And Four-Fold Reduction, Guy Rozenman
Electronic Theses & Dissertations (2024 - present)
Corannulene is a bowl-shaped π-conjugated fragment of the ball-shaped C60-fullerene that undergoes stepwise multielectron reduction and can accept four electrons to form the aromatic tetraanion, C₂₀H₁₀⁴⁻. Prior literature has established this charge state in donor-solvated alkali-metal assemblies: early solution studies identified the formation of the tetraanion under lithium reduction in THF, and later X-ray diffraction crystallography demonstrated a triple-decker lithium sandwich in which two corannulene tetraanion decks encapsulate five Li⁺ ions. The central objective of this thesis is to determine whether the corannulene tetraanion can instead be isolated as a bulk solvent-free alkali-metal salt containing only corannulene and …
Development Of Photolabile Coumarin Linker For Rna Synthesis And Crisprcas9 Applications, Ian Mcclain
Development Of Photolabile Coumarin Linker For Rna Synthesis And Crisprcas9 Applications, Ian Mcclain
Electronic Theses & Dissertations (2024 - present)
The scope of RNA-based therapeutics continues to expand as more siRNA, mRNA, and CRISPR-based treatments are approved for various medical applications. Purification of synthetic RNA drugs is inherently challenging and requires considerable time and resources. New cost-effective and efficient purification strategies will expedite drug development process and will lower the drug costs. In this thesis I describe two generations of photolabile linkers for the non-chromatographic purification of therapeutic RNAs. In addition, the photolabile linker was utilized for regulation CRISPR-Cas9 gene editing. In the first part of the thesis, I describe the first generation of the photolabile coumarin-based linker for non-chromatographic …
Superelectrophile Promoted Synthesis Of Heterospirocycles, Mariam A. Adegbenro
Superelectrophile Promoted Synthesis Of Heterospirocycles, Mariam A. Adegbenro
Graduate Research Theses & Dissertations
Spirocycles are important scaffolds with a wide range of applications in material science as well as in medicine. The introduction of a heteroatom into the spirocyclic framework can improve its electronic, photophysical, and structural properties. Various reports have been published on the incorporation of atoms other than carbon into the spirocycle. The work outlined in this dissertation involves the development of synthetic methodologies for the synthesis of hetero-spirocycles via superacid-promoted cyclization reactions. These concepts are summarized in Chapter 1.
Chapter 2: Aromatic imines were prepared from 9-fluorenone and azafluorenones, and these substrates were reacted in the Brønsted superacid, triflic acid, …
Utilizing Coal For Mesophase Pitch-Based Carbon Fiber Production: Precursors, Processes, And Progress, Christina M. Thompson
Utilizing Coal For Mesophase Pitch-Based Carbon Fiber Production: Precursors, Processes, And Progress, Christina M. Thompson
Theses and Dissertations--Chemistry
Graphitic materials possess unique properties due to the unique combination of layered crystalline structure and carbon’s low atomic weight. High performance carbon fiber is one such example, displaying exceptional strength-to-weight ratios, stiffness, and thermal and chemical resistance. These properties render high performance carbon fiber a critical structural reinforcement material in the manufacture of composites across various industries, such as for automotive and aerospace applications. However, balancing fiber performance with precursor and processing costs remains a challenge. As alternative carbonaceous feedstocks are explored, coal has gained interest for utilization in graphitic products as a relatively abundant and low-cost source of aromatic …
The Chemistry Of Red Lipstick: The Impact Red Lipstick Has On Society, Lilliana Weldeslassie
The Chemistry Of Red Lipstick: The Impact Red Lipstick Has On Society, Lilliana Weldeslassie
Electronic Theses & Dissertations (2024 - present)
Cosmetic chemistry is deeply embedded in everyday life, shaping the products people use from morning to night. Among these, red lipstick stands out as a formulation that blends complex chemistry with a cultural meaning. This thesis examines the scientific foundations of red lipstick through its chemical composition, pigment structure, toxicological history, analytical methods, and evolving sustainability practices. Historically, red lipsticks relied on high-risk ingredients such as lead, mercury, and other toxic metals, reflecting an era before chemical safety and regulatory oversight were incorporated.21 Modern formulations have established safer synthetic dyes, natural waxes, plant-based oils, and stabilizers created to optimize …
Bio-Orthogonal Chemistry-Based Strategy To Turn-On And Turn-Off Crispr-Cas9 Gene Editing In Solution And In Live Cells, Bhoomika Pandit
Bio-Orthogonal Chemistry-Based Strategy To Turn-On And Turn-Off Crispr-Cas9 Gene Editing In Solution And In Live Cells, Bhoomika Pandit
Electronic Theses & Dissertations (2024 - present)
The CRISPR–Cas9 system is a widely popular tool for genome engineering. There is a strong interest in developing tools for temporal control of CRISPR-Cas9 activity to address some of the challenges and to broaden the scope of potential applications. In this thesis I describe two biorthogonal based approaches to either Turn-ON and Turn-OFF CRISPR-Cas9 gene editing.
In first project work I describe a bio-orthogonal chemistry-based approach to Turn-ON Cas9 nuclease activity with temporal precision. We report a TCO-acylimidazole reagent that acylates 2′-OH groups of RNA. Poly-acylation (“cloaking”) of RNA was optimized in vitro using a model 18-nt oligonucleotide, as well …
Balancing Evidence Recovery: Hexane’S Effect On Biological And Non-Biological Traces In Sexual Assault Kits, Maya Richards
Balancing Evidence Recovery: Hexane’S Effect On Biological And Non-Biological Traces In Sexual Assault Kits, Maya Richards
Honors Undergraduate Theses
This study investigated the effectiveness of solvent – based extraction methods for the recovery of lubricant residues from simulated sexual assault swabs, with emphasis on balancing chemical evidence recovery. Sequential extraction using ultra – pure water followed by organic solvents, hexane, dichloromethane (DCM), and ethyl acetate (EA), was evaluated across water – based, silicone – based, oil – based, and hygiene product matrices. Analysis was performed using Direct Analysis in Real Time – High Resolution Mass Spectrometry (DART – HRMS), and extraction efficiency was assessed through spectral correlation with neat reference samples. Results demonstrated that solvent performance was highly dependent …
Design, Syntheses And Biological Applications Of Fluorescent Probes For Nad(P)H, Hsa And Cellular Microenvironment Sensing, Adenike M. Olowolagba
Design, Syntheses And Biological Applications Of Fluorescent Probes For Nad(P)H, Hsa And Cellular Microenvironment Sensing, Adenike M. Olowolagba
Dissertations, Master's Theses and Master's Reports
Fluorescent probes have emerged as powerful tools for investigating complex biological processes due to their high sensitivity, selectivity, and capability for real-time, non-invasive imaging. In particular, the detection of key biomolecules such as NAD(P)H, viscosity-related parameters, human serum albumin (HSA), and pH is essential for understanding cellular metabolism, redox homeostasis, and disease progression. In Chapter 2, three coumarin-based fluorescent probes (A–C) were designed, synthesized, and characterized for monitoring NAD(P)H levels in living cells. Probes A and B feature coumarin–cyanine hybrid structures linked via vinyl and thiophene bridges to 3-quinolinium acceptors, respectively, while probe C incorporates a dicyano moiety to replace …
Salicylic Acid Heterocyclic Derivatives: Chemical Synthesis And Biological Activity, Rawaa Hefdi Zaooli, Marwa Abdulameer Mseer, Amneen Mohammed Alsayegh
Salicylic Acid Heterocyclic Derivatives: Chemical Synthesis And Biological Activity, Rawaa Hefdi Zaooli, Marwa Abdulameer Mseer, Amneen Mohammed Alsayegh
Al-Bahir
Before a drug can be widely used, it must go through a long development process, starting from the discovery of the active ingredient and continuing with tests to confirm its safety and effectiveness. In this study, new olsalazine derivatives were synthesized, containing a fused morpholine-3-one ring and two five-membered heterocyclic rings (thiadiazole and oxadiazole). Common and readily available materials, such as salicylic acid (to prepare 2-hydroxy-5-nitrobenzoic acid) and inexpensive catalysts, were used to synthesize compounds from the first, 5,5'-(diazene-1,2-diyl)bis(2-hydroxy-3-nitrobenzoic acid) (A1), to the seventh, 6,6'-(diazene-1,2-diyl)bis(N-(4-(5-amino-1,3,4-oxadiazol-2-yl)phenyl)-3-oxo-3,4-dihydro-2H-benzo[b][1,4]oxazine-8-carboxamide) (A7).
Each compound was characterized by FT-IR and ¹H-NMR spectroscopy, along with physical properties such …
Discovery Of The Multi-Ion Bridge Intermediate: A Computational Exploration Of The Mechanism For Azomethine Ylide Formation From N-Oxides, Martin J. Neal
Discovery Of The Multi-Ion Bridge Intermediate: A Computational Exploration Of The Mechanism For Azomethine Ylide Formation From N-Oxides, Martin J. Neal
Electronic Theses and Dissertations
Density functional theory (DFT) provides a method for calculating the ground-state energies of complex molecular systems through evaluating the electron density instead of the full wave function. When results match either experimental outcomes, calculations with DFT offer a computationally efficient method to help explain chemical phenomena. The transformation of tertiary amine N-oxides to azomethine ylides, a simple route to the precursor for 1,3-dipolar cycloadditions that result in the pyrrolidine scaffolds found in natural products, has received only minimal attention due to concerns that its mechanism includes a highly electrophilic intermediate. Utilizing DFT to model the mechanism of the conversion …
Steam Distillation And Characterization Of Star Anise: Investigating Aroma And Aromaticity, Natalie Brattain
Steam Distillation And Characterization Of Star Anise: Investigating Aroma And Aromaticity, Natalie Brattain
Discovery Day - Daytona Beach
"Steam distillation is a widely used technique for extracting essential oils from plant materials, allowing for the separation of volatile compounds while minimizing thermal degradation. In this study, steam distillation was used to extract the essential oil of Illicium verum (Star Anise) to investigate the relationship between aroma and aromaticity. While ""aroma"" refers to the sensory perception of a substance’s scent, ""aromaticity"" is a chemical property related to the stability of conjugated ring systems. This distinction for our compound was explored by using chemical characterization of the extracted oil. Following the steam distillation process, gas chromatography (GC) and mass spectrometry …
Fermented Foul Play: A Real-World Forensic Scenario To Enhance Student Engagement And Understanding Of Instrumentation And Analytical Data Analysis, Abigail Hoermann, Laci Joy Walmer, Matthew J. Goss
Fermented Foul Play: A Real-World Forensic Scenario To Enhance Student Engagement And Understanding Of Instrumentation And Analytical Data Analysis, Abigail Hoermann, Laci Joy Walmer, Matthew J. Goss
Student Scholar Symposium
A forensic-style investigation was introduced in an upper-level instrumental analysis course to foster collaboration and application of theoretical concepts in a laboratory setting. Students were provided with kombucha samples collected from a simulated crime scene and tasked with determining ethanol concentrations using Gas Chromatography–Mass Spectrometry (GC-MS). By independently preparing serial dilutions, establishing calibration curves, and interpreting mass spectra, they practiced quantitative analytical techniques and engaged in evidence-based problem solving. Notably, Sample C demonstrated elevated ethanol levels (6.4% v/v), suggesting possible adulteration and deepening the forensic narrative. Through this scenario-driven format, students strengthened both their technical competencies and their ability to …
Photoflow Synthesis And Characterization Of Cis- And Trans-N-Isohumulone, Gregory M. Giovine, Bradley Gallow, Trevor Smith, Bruce Hamper
Photoflow Synthesis And Characterization Of Cis- And Trans-N-Isohumulone, Gregory M. Giovine, Bradley Gallow, Trevor Smith, Bruce Hamper
Undergraduate Research Symposium
Previously published efforts by the Hamper group demonstrated the viability of photochemistry in the isomerization of n-humulone to n-isohumulone. Photochemical isomerization reactions of n-humulone performed under 400nm light over 8 hours resulted in high yields (84% reported) of largely trans-n-isohumulone (>95%). These promising results invited further examination of the photochemical process and the application of photoflow procedure. Herein we report the beginnings of a comprehensive slate of n-humulone isomerization reactions performed under iterative photoflow conditions.
The Chemistry Of Color: A Comparative Analysis Of Natural And Synthetic Dyes In Textile Application, Caitlyn Pinaga Cpht
The Chemistry Of Color: A Comparative Analysis Of Natural And Synthetic Dyes In Textile Application, Caitlyn Pinaga Cpht
Honors Program Theses and Research Projects
The Chemistry of Color: A Comparative Analysis of Natural and Synthetic Dyes in Textile Application examines how color functions at the intersection of chemistry, culture, and environmental responsibility. This project traces the evolution of dyeing from ancient natural pigment traditions, rooted in ecological knowledge, agricultural practices, and cultural identity, to the industrial rise of synthetic dyes, whose laboratory precision enabled unprecedented consistency, brightness, and global textile expansion. Through experimental swatch analysis, the study compares the behavior of natural dyes derived from plants and food sources with modern fiber-reactive and synthetic dye classes on a range of fibers including cotton, bamboo …
The Malonate Template: The Key To Unlocking Novel Amino Acids, Thomas Owens
The Malonate Template: The Key To Unlocking Novel Amino Acids, Thomas Owens
Dissertations
The “Malonate Template” provides access to various amino acids, all from a common intermediate. Herein, demonstrates the use of the malonate template to establish a synthetic route to both 2-thiohistidine and 2-thio-3-N-methyl-histidine from a benzyl methyl malonate derived intermediate. Furthermore, efforts exploiting the applicability of the malonate template for the of both 2-thiohistidine and 2-thio-3-N-methyl-histidine as a suitable alternative to methods previously described by Erdelmeier are described.
The method presented incorporates modifications to the biomimetic pathway described by Erdelmeier for the synthesis of 2-thiohisidine. By exploiting the biomimetic formation of 2-thiohisitidne’s mechanism via mass spectrometry, we …
Geochemical Analysis Of The Eagle Ford Shale In Webb And Dimmit Counties, Tx, Natalie G. Girlinghouse
Geochemical Analysis Of The Eagle Ford Shale In Webb And Dimmit Counties, Tx, Natalie G. Girlinghouse
Electronic Theses and Dissertations
The Late Cretaceous Eagle Ford Shale of South Texas is a mixed carbonate–siliciclastic succession that serves as both a prolific hydrocarbon source and reservoir. This study integrates chemostratigraphy, mineralogical analysis, and elemental ratio proxies to reconstruct depositional environments and assess controls on detrital influx, paleoproductivity, and redox conditions across multiple cores in Webb and Dimmit counties. Major, trace, and redox-sensitive elements were evaluated alongside Total Organic Content (TOC) and carbonate content to identify stratigraphic trends and environmental shifts.
Results reveal distinct geochemical signatures between the Upper and Lower Eagle Ford Shale, with the Lower Eagle Ford characterized by elevated Al-rich …
Catalytic Synthesis Of Iron-Doped Graphitic Aerogels From Poly(Phloroglucinol-Terephthalaldehyde – Urethane) Precursors, Stephen Yaw Owusu, Rushi U. Soni, Chariklia Sotiriou-Leventis
Catalytic Synthesis Of Iron-Doped Graphitic Aerogels From Poly(Phloroglucinol-Terephthalaldehyde – Urethane) Precursors, Stephen Yaw Owusu, Rushi U. Soni, Chariklia Sotiriou-Leventis
Chemistry Faculty Research & Creative Works
We report a new class of graphitic carbon aerogel precursors based on iron oxide-doped poly(phloroglucinol-terephthalaldehyde–urethane) (T-POL/PU-FeOx) networks. The hybrid polymeric network incorporates a rigid aromatic triisocyanate, tris(4-isocyanatophenyl)methane, which reacts in situ with the hydroxyl groups of phloroglucinol to form a polyurethane-containing framework. Monolithic aerogels derived from this system undergo catalytic graphitization at significantly reduced temperatures (800–1500 °C) compared to conventional graphitization (2500–3300 °C). An oxidative ring fusion aromatization step (240 °C, air) prior to pyrolysis enhanced the degree of graphitization. The resulting graphitic aerogels were characterized by XRD, Raman spectroscopy, TGA, TEM, SEM, XPS, and N₂ sorption porosimetry. Compared to …
N-Aryl Phenoxazines As Polymer Supported Photocatalysts, Mary Kathryn Hall
N-Aryl Phenoxazines As Polymer Supported Photocatalysts, Mary Kathryn Hall
Master's Theses
In photosynthesis, the energy of sunlight is perfectly harnessed to facilitate the production of small molecules that are essential for plant life on earth. Inspired by this model of energy efficiency and simplicity, this work seeks to mimic that ability to use the energy in visible light to perform new and more efficient chemistries. Just like in photosynthesis, photocatalysts can act as chromophores absorbing light to excite electrons opening new pathways for previously untapped reactivity. Recent research has provided a wide range of small molecule reactions that are made possible or easier by the use of a photocatalyst. However, these …
Synthesis And Study Of Stable Organic Radicals For Mri Contrast Agents And New Materials, Sabina Dhakal
Synthesis And Study Of Stable Organic Radicals For Mri Contrast Agents And New Materials, Sabina Dhakal
Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–
The first part of this dissertation focuses on the design, synthesis, and characterization of a thermally robust S =1/2 phototetrazolinyl monoradical and the development of synthetic methodologies for a high-spin (S = 1) phototetrazolinyl diradical. Electrochemical studies of the phototetrazolium cation (precursor to the monoradical) revealed a remarkably narrow electrochemical band gap (Ecell ≈ 0.82 V), suggesting promising electrical conductivity. Thermal analysis of the monoradical demonstrated excellent stability, with the onset of decomposition at 232 °C. Building on the excellent thermal stability and promising properties for electrical conductivity of the monoradical, we developed two condensation-based synthetic routes that provide viable …
Novel Radical Chemistry Of Electron-Rich Double Bonds, Claire Allyson Beard
Novel Radical Chemistry Of Electron-Rich Double Bonds, Claire Allyson Beard
Graduate Theses and Dissertations
This work delves into the reactivity of nucleophilic N-heterocyclic carbenes (NHCs) and their ability to form electron-rich alkene intermediates, which can undergo various chemical transformations depending on the nature of the electrophile. Initial reports by Hahn disclosed the NHC promoted radical nature of electron-rich N,N’-benzyltetraazafulvalenes, which led to 2,2’- biimidazoles. We found that N-aryl substituted pyridinium salts also underwent rapid a similar NHC promoted dimerization when exposed to a base, producing 2,2’-bipyridyls. This is likely due to the adept radical nature of the bipyridinylidene intermediate for C-Naryl bond scission. We have also uncovered an unprecedented C-N bond scission of Breslow-like …
Free Radical Reactions Of Electron Rich Alkenes, David A. May Jr
Free Radical Reactions Of Electron Rich Alkenes, David A. May Jr
Graduate Theses and Dissertations
Radical reactions have known for over a century but have only been thought of as useful synthetic strategies for the last 70 years. During this period, much work has been done to develop theoretical explanations for their reactivity and modes of termination, resulting in them becoming a fundamental type of organic reaction in academia and industry. Previous studies by the McIntosh group have shown that a radical [1,3]-Rearrangement occurs when N-substituted pyridines are heated. Here, the scope of this new reaction is expanded to include polycyclic pyridines including neocuproine (2,9-dimethylphenanthroline) and 2-methylquinoline while also expanding the range of reactions available …
Versatile Nitration Of Bodipy Dyes Using No₂Bf₄: Effects Of Nitro Substituents On Spectroscopic And Self-Assembly Properties, Caroline Sarange Gwaro
Versatile Nitration Of Bodipy Dyes Using No₂Bf₄: Effects Of Nitro Substituents On Spectroscopic And Self-Assembly Properties, Caroline Sarange Gwaro
LSU Master's Theses
This study explores the regioselective nitration of BODIPY dyes at the 2, 3- and 2,6-positions using nitronium tetrafluoroborate (NO₂BF₄), offering a high-yielding and mild synthetic route. The introduction of nitro groups significantly alters the dyes’ photophysical and self-assembly properties. Mono-nitrated BODIPYs exhibit hypsochromic shifts in absorption and emission spectra, increased dipole moments, enhanced Stokes shifts, and reduced molar absorptivity. In contrast, di-nitrated analogs show bathochromic shifts and decreased dipole moments in both ground and excited states. Spectroscopic characterization was performed using UV-vis and fluorescence spectroscopy, supported by density functional theory (DFT) calculations. Self-assembly behavior was investigated in polar (acetonitrile) and …
3d Visualization For Teaching And Learning In Organic Chemistry: Orbital Hybridization And Bonding, Bao Le, Jeffrey Hansen
3d Visualization For Teaching And Learning In Organic Chemistry: Orbital Hybridization And Bonding, Bao Le, Jeffrey Hansen
Annual Student Research Poster Session
This research focuses on developing techniques to create 3D visualizations for use in an electronic textbook. In this age of technology, traditional textbooks have become less appealing to the new generation compared to phones or tablets. Student learning can be enhanced by not only bringing the textbook online but also elevating the comprehensive experience for the students with 3D animations. We will show how animations of orbital hybridization and chemical bonding are made in Blender using Signed Distance Field (SDF) modeling. The orbitals’ models are mathematically combined allowing for smooth animation. We have used this technique to animate the transformation …
Creating Blender Animations To Help Students Visualize Organic Chemistry Concepts, Vasilina Vikareva, Jeffrey Hansen
Creating Blender Animations To Help Students Visualize Organic Chemistry Concepts, Vasilina Vikareva, Jeffrey Hansen
Annual Student Research Poster Session
Many students struggle with organic chemistry because they find it difficult to visualize molecular structures and interactions in three dimensions. Concepts like bond rotation for conformational isomers and intermolecular forces require strong spatial imagination, which traditional 2D drawings fail to develop effectively. This spatial visualization deficit contributes significantly to high failure rates and student anxiety in organic chemistry courses, creating a substantial barrier to success in STEM fields. This project aims to solve this problem by creating animations that demonstrate complex chemical concepts in clear, visual ways that enhance student comprehension and retention. The research methodology involves developing a comprehensive …
High-Capacity, Reversible, And Energy-Efficient Water Vapor Sorption By Hierarchical Micro-To-Macroporous Carbon Aerogels From Polybenzoxazine And Polybenzodiazine, Vaibhav A. Edlabadkar, Rushi U. Soni, Stephen Y. Owusu, A. B.M.Shaheen Ud Doulah, Nicholas Leventis, Chariklia Sotiriou-Leventis
High-Capacity, Reversible, And Energy-Efficient Water Vapor Sorption By Hierarchical Micro-To-Macroporous Carbon Aerogels From Polybenzoxazine And Polybenzodiazine, Vaibhav A. Edlabadkar, Rushi U. Soni, Stephen Y. Owusu, A. B.M.Shaheen Ud Doulah, Nicholas Leventis, Chariklia Sotiriou-Leventis
Chemistry Faculty Research & Creative Works
Quantitative, reversible water vapor sorption is in rising demand for applications ranging from home appliances to atmospheric water harvesting. However, most sorbents suffer from low water-uptake capacities, nonreusability, and especially high regeneration temperatures. This study addresses this challenge by introducing polybenzoxazine- (PBO) and polybenzodiazine-derived (PBDAZ) carbon aerogels as reversible high-capacity desiccants. PBO and PBDAZ aerogels were prepared from structurally related monomers via HCl-catalyzed ring opening polymerization. Both types of aerogels were first aromatized at 200–240 °C under air or O2 and then were carbonized at 800 °C under Ar. These as-prepared carbon aerogels were further etched at 1000 °C under …