DIRECT ARYLATION OF UNACTIVATED ARENE USING EARTH ABUNDANT IRON/TETRA-AZA MACROCYCLIC COMPLEX

Type: Graduate
Author(s): Tahmina Afroz Chemistry & Biochemistry
Advisor(s): Kayla Green Chemistry & Biochemistry
Location: SecondFloor, Table 7, Position 3, 1:45-3:45

DIRECT ARYLATION OF UNACTIVATED ARENE USING EARTH ABUNDANT IRON/TETRA-AZA MACROCYCLIC COMPLEX
The development of sustainable catalytic systems for carbon–carbon bond formation is of critical importance in modern synthetic chemistry. This study presents an iron-based catalytic system employing tetra-aza macrocyclic ligands as a cost-effective and environmentally benign alternative to palladium in direct arylation reactions. Using [Fe²⁺L6(Cl)₂] as the catalyst and molecular oxygen as the terminal oxidant, the direct C(sp²)–C(sp²) coupling of pyrrole with substituted phenylboronic acids was achieved under mild conditions, yielding 2-phenylpyrrole and its derivatives with moderate efficiency (up to 62%). The catalyst displayed broad substrate scope and functional group tolerance, effectively accommodating halogen, nitro, alkyl, and methoxy substituents. Mechanistic studies excluded a radical-mediated pathway and instead supported a non-radical oxidative mechanism involving an iron(III)-hydroperoxo intermediate. These findings underscore the potential of earth-abundant iron complexes in sustainable cross-coupling chemistry and set the stage for further exploration in heterocycle functionalization and pharmaceutical scaffold development.

Towards a Comprehensive Benchmark of Quantum Mechanical pKa Prediction: Conformational Sampling, Model Solvent, Basis Set, Density Functional, and Empirical Corrections for the SAMPL7 Dataset

Type: Graduate
Author(s): Donatus Agbaglo Chemistry & Biochemistry Minh Ho Biology
Advisor(s): Benjamin Janesko Chemistry & Biochemistry

Reimagined Route to Drug Discovery: Macrocyclization leads to 20 predicted and persistent products for chemical library development

Type: Graduate
Author(s): Liam Claton Chemistry & Biochemistry
Advisor(s): Eric Simanek Chemistry & Biochemistry
Location: SecondFloor, Table 8, Position 3, 11:30-1:30

In the pursuit of new ways to develop libraries of compounds for pharmaceutical drug discovery, the utilization of a robust and tunable macrocycle synthetic scaffold has led to the discovery of persistent and structurally well-defined conformational isomers. Targeting these macrocycles that exist as an ensemble of preorganized conformations represents a compromise between the pursuit of flexible molecules of undefined structure and rigid molecules biased towards a single conformation. This system is based on the quantitative dimerization of a monomer to afford macrocycle. When a single monomer is used, six unique structures are obtained. When two monomers are used, twenty unique structures are obtained. These different structures (conformational isomers) are accessed via hindered bond rotation with a barrier of ~18 kcal/mol and are observable by ¬1H NMR. Current drug discovery methods heavily rely on screening large chemical libraries of small, ridged molecules against protein targets and typically sacrifice entropy in favor of stronger ligand-target binding. Using our system, synthesis of 50 monomers allows for the generation of a library of over 10,000 structurally unique macrocycles. The goal of this work is to provide new chemical libraries for drug discovery.

Testing the Fundamental Kinetic Properties of Anti-Aging, Antioxidant Active Ingredients for Skincare

Type: Graduate
Author(s): Nora Del Bosque Chemistry & Biochemistry
Advisor(s): Kayla Green Chemistry & Biochemistry
Location: Basement, Table 5, Position 1, 1:45-3:45

EUK-134 is a manganese-salen complex widely used in anti-aging skincare formulations due to its potent antioxidant activity resulting from catalytic decomposition of reactive oxygen species. Despite its popularity, the fundamental kinetic properties that govern its efficacy and recyclability are not well understood, limiting its optimization in skincare products. As a result, the study presented here investigates the efficiency, sustained activity, and selectivity of EUK-134 in comparison to the Green lab ligand library by evaluating its turnover number (TON), turnover frequency (TOF), and reaction rate. Results indicate that while EUK-134 demonstrates high catalase-type activity and selectivity, the activity decreases with continuous exposure to H₂O₂, suggesting a need for re-application in real-world scenarios to achieve long-term protection. Additionally, selectivity studies show that peroxidase activity was observed, which may impact the stability of sensitive ingredients in formulations. These findings provide essential kinetic benchmarks to compare future small molecules and optimize EUK-134’s use in antioxidant skincare products. Without a clear understanding of these fundamental properties, we lack benchmarks to compare future small molecules that compete with EUK-134.

Influence of the Quinoline Moiety on the Pharmacological Properties of Tetra-aza Pyridinophanes and Their Anticancer Activity

Type: Graduate
Author(s): Sarah Dunn Chemistry & Biochemistry
Advisor(s): Kayla Green Chemistry & Biochemistry
Location: SecondFloor, Table 5, Position 1, 1:45-3:45

The development of novel anticancer agents with enhanced selectivity and reduced toxicity remains a critical challenge in medicinal chemistry. In this study, we investigate the influence of the quinoline moiety on the pharmacological properties of tetra-aza pyridinophanes, with a focus on their anticancer activity. A series of structurally diverse derivatives were synthesized, incorporating variations in the quinoline moiety position and R-group functionalization. The compounds were characterized using multiple spectroscopic and analytical techniques, and their biological activity was evaluated in cancer cell lines. Results indicate that the presence of the quinoline moiety significantly improves anticancer efficacy compared to its absence, suggesting enhanced interactions with cellular targets. Furthermore, permeability studies reveal that the methoxy (-OMe) substitution on the pyridine ring enhances cellular uptake relative to the hydroxyl (-OH) counterpart. These findings highlight the potential of quinoline-functionalized tetra-aza pyridinophanes as promising candidates for targeted cancer therapy. By improving the selectivity between normal and cancerous cells, this work advances the design of next-generation chemotherapeutics with reduced systemic toxicity.

The Goldilocks Combination to Unprecedented Perovskites

Type: Graduate
Author(s): Maegyn Grubbs Chemistry & Biochemistry Sergei Dzyuba Chemistry & Biochemistry Zygmunt Gryczynski Physics & Astronomy Bong Lee Physics & Astronomy
Advisor(s): Jeff Coffer Chemistry & Biochemistry
Location: Basement, Table 4, Position 2, 11:30-1:30

Metal-halide perovskites are crystalline semiconductive materials with a tunable direct bandgap, defect tolerance, and high charge carrier mobility. These useful properties have led to application perovskites such as LEDs, solar cells, and more recently lasers.
In this project, cetyl ionic liquid (IL) enhanced Methylammonium Lead Tribromide perovskites thin films were studied on substrates with varying refractive indices to determine how refractive index impacts photophysical properties. Methylammonium Lead Tribromide perovskites have a refractive index of 2.19. In comparison glass, a common substrate, has a refractive index of 1.51 while yttrium-stabilized zirconium oxide (YSZ) is 2.15.
Thin films of Methylammonium Lead Tribromide grown on yttrium-stabilized zirconium oxide (YSZ) in the presence of an ionic liquid are found to be strongly emissive in the green at a wavelength of 535 nm (with quantum efficiency values above 60%). The associated photoluminescence excitation (PLE) spectra show an unprecedented series of distinct peaks, one set with an average energy separation of ~200 milli-electron volts, the other set with a ~100 milli-electron volt separation indicating possible Giant Rashba Splitting. The preparation and structure of these films, along with origins of this splitting, are presented.

P-Stereogenic Phosphorus Compounds as Organocatalysts for Asymmetric Synthesis

Type: Graduate
Author(s): Ellis Guernsey Chemistry & Biochemistry
Advisor(s):
Location: Basement, Table 6, Position 3, 11:30-1:30

Asymmetric chemical transformations are essential, given that most pharmaceuticals are chiral. However, the industrial implementation of an asymmetric catalyst relies on basic economic principles. For an economically viable synthesis, catalysts should be readily available, cost-effective, and environmentally sustainable. We are synthesizing and evaluating a series of chiral phosphorus acids (CPAs) as catalysts for asymmetric transformations. Building on our previous work, we are developing P-chiral phosphorus acids as Brønsted acid catalysts for the acid-catalyzed asymmetric transformations.

Cancelling Cancer through Copper capture

Type: Graduate
Author(s): David Mingle Chemistry & Biochemistry
Advisor(s): Kayla Green Chemistry & Biochemistry

Copper plays particularly important roles in tumor growth and metastasis, making it a new target for anti-cancer therapies. The goal of this project is to exploit the pathways that cancer uses for proliferation as a target to inhibit cancer cell growth. To achieve this, tetra-aza macrocyclic small molecules will be used to sequester copper from the copper metabolizing pathways, recently we have discovered these molecules have high affinity for copper, water solubility, low toxicity, available in gram-quantities, and well-characterized. Our lead compound will be evaluated for anticancer activity on normal and breast cancer cells. This project also seeks to examine the pharmacological properties of the lead compound and explore of our compound on cooper pathways that leads to oxidative stress and inflammation.

Salt-Induced Diffusiophoresis of a Cationic Micelle in Water. Determination of Cross-Diffusion Coefficients

Type: Graduate
Author(s): Khanh Nguyen Chemistry & Biochemistry Minh Le Chemistry & Biochemistry
Advisor(s): Onofrio Annunziata Chemistry & Biochemistry
Location: FirstFloor, Table 1, Position 1, 11:30-1:30

Salt-induced diffusiophoresis is the movement of a charged nanoparticle in water, driven by an imposed directional gradient of salt concentration. This transport phenomenon has become a valuable tool for manipulating charged nanoparticles within porous materials and microfluidic systems. Micelles are a typical example of nanoparticles with the important ability to host small guest molecules. Therefore, micelle diffusiophoresis is also crucial for manipulating small molecules. This poster reports measurements of diffusiophoresis coefficients carried out on aqueous mixtures of the surfactant, hexadecylpyridinium chloride (CPC) in the presence of NaCl by Rayleigh interferometry. Measurements of NaCl osmotic diffusion from high to low micelle concentration are also reported. We observe that diffusiophoresis of CPC cationic micelles occurs from high to low salt concentration. A model describing the behavior of micelle diffusiophoresis as a function of NaCl concentration is reported. Our diffusiophoresis results are explained in terms of micelle electrical charge, salt osmotic diffusion coefficients and zeta potential. This work offers new insights into diffusiophoresis of charged nanoparticles with potential applications for enhanced-oil recovery from porous rocks, soil remediation and diffusion-based mixing inside microfluidics.

Europium-doped Cerium Oxide Nanotubes as a potential probe for bioimaging and optical sensors

Type: Graduate
Author(s): Leonardo Ojeda Hernandez Chemistry & Biochemistry Kayla Brownell Chemistry & Biochemistry Joseph Chouinard Physics & Astronomy
Advisor(s): Jeffery Coffer Chemistry & Biochemistry
Location: SecondFloor, Table 1, Position 2, 11:30-1:30

The development of cerium oxide (CeO2) nanomaterials is rapidly advancing, driven by their wide range of applications in catalytic converters, solid oxide fuel cells, and biological sensors. Considering this, doping CeO2 with rare earth elements such as Europium (Eu3+) not only enhances its catalytic properties but also adds visible fluorescence to the list. To explore the variability of this effect, Eu3+ doped CeO2 nanotubes were synthesized and carefully analyzed by varying the Eu3+ concentration to investigate their optical properties, crystallinity, and morphology. Current research is focused on evaluating the potential of these doped CeO2 nanotubes as probes for bioimaging and optical sensors.