UCLA

Chem 263 Seminars in Chemical Biology: Heta Desai
2023-05-30 16:00 - 17:30 (America/Los_Angeles) | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

Jeffrey I. Zink Inorganic Chemistry Seminar Series: Rebecca J. Abergel
2023-05-31 13:00 - 14:30 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States
Flyer: Prof. Rebecca Abergel Flyer
Title: Heavy elements in nature: from waste management to precision medicine
Abstract: From the potential contamination of individuals with radioactive fission products after a nuclear accident to the therapeutic use of radioisotopes for cancer diagnostics and treatment, the nuclear, coordination, and biological chemistry of actinides have become increasingly relevant to a number of applied problems. Understanding the fundamental bonding interactions of selective metal assemblies presents a rich set of scientific challenges and is critical to the characterization of f-element coordination chemistry, and to the development of highly efficient separation reagents or new therapeutic agents. Our approach to these challenges uses a combination of biochemical and spectroscopic studies on both in vitro and in vivo systems to characterize and tune the selective binding of man-made, f-block metal ions by natural and biomimetic ligand architectures. These studies will be discussed with a focus on emerging applications in separation, isotope production, and medicine.

Chemistry and Biochemistry Departmental Award Ceremony
2023-05-31 15:00 - 18:00 | CNSI Auditorium
Join the Department of Chemistry and Biochemistry for our annual Departmental Award Ceremony!
We are honored to recognize the achievements and research done by our Undergraduate/Graduate/Postdoctoral Researchers, as well as the leadership and administrative contributions from our Faculty and Staff throughout the 2022-2023 Academic Year.
We hope to see you at this celebratory Award Ceremony!

Chem 218 Student Exit Seminar: Danny Robertson
2023-06-01 12:00 - 13:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

Houk-Jung Organic Colloquium 247: Andrei Yudin
2023-06-01 16:00 - 17:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States
Yudin Flyer
Synthetic Half-Reactions
Abstract: This lecture will describe the concept of synthetic half-reactions and its applications towards understanding the interplay of chemical reactivity and conformational interconversions. Apart from electrochemistry, which offers half-reaction formalism to predict reactivity, there is no accepted system that dissects chemical transformations into simple components with the goal of matching uphill steps with cognate downhill processes. Such a system would allow one to look at organic reactivity from a different perspective, deemphasizing the role of molecular orbitals in favor of more intuitive enthalpic arguments. Given the frequent, although often questionable, use of the term “driving force” in organic chemistry, it stands to reason that such treatment of reactivity is long overdue. I will describe the origins of the theory of synthetic half-reactions and demonstrate their utility on examples from our and others’ laboratories.

Dickerson Biochemistry Seminar - Lily Taylor and Cindy Wang
2023-06-02 15:30 - 16:30 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

MACS Careers in Chemistry Seminar Series | Dr. Selma Duhovic | Prepel (X)
2023-06-02 16:00 - 17:00 | Mol Sci 3440, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States
2June2023 MACS Careers in Chemistry Seminar

Physical Chemistry Seminar 228: Scott Cushing
2023-06-05 16:00 - 17:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States
Prof. Cushing Flyer
Title: From Batteries to Photoelectrochemistry: Exploring Ultrafast Phenomena with Electrons, X-rays, and Entangled Photons
Abstract: The Cushing lab focuses on ultrafast instrumentation building that ranges from tabletop X-rays, entangled photon spectroscopy, ultrafast TEM/EELS, to new forms of battery spectroscopy. In this talk, I will give a brief introduction to our research areas, mentioning the increasingly “null” space explored with entangled photons, and then focus on two of the techniques – table top X-ray spectroscopy and our newly created laser-driven ultrafast impedance method. First, we use transient X-ray techniques to element-specifically explore complex photodynamics in solar to fuel and other solid-state systems. The ultrafast X-ray pulses measure a mix of electronic and structural dynamics, and using our excited state Bethe-Salpeter equation approach, we can extract everything from time-resolved electron and hole energies, defect state occupations, phonon and polaron modes, and transport in multi-layer junctions. New examples include measuring a lattice’s coherent response to polaron formation and dynamic localization in superatomic crystals. Second, we use our newly developed, laser-driven ultrafast impedance method to investigate the ion hopping Hamiltonian of superionic conductors. Picosecond temporal and spectral correlations differentiate electron-ion, electron-phonon, and even potentially ion-ion interactions. Follow up transient XUV studies can then give an atomistic view of how material parameters control solid-state electrolyte and electrode performance.

Special Seminar: Research in Chemical Education and STEM Pedagogy: Dr. Heather Tienson-Tseng
2023-06-06 14:30 - 15:30 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States
Flyer: Dr. Heather Tienson-Tseng Flyer
Title: Using Assessment to Inform Instructional Changes
Abstract: An integral aspect of education is assessment, but what is the purpose of assessment, and what can we do to better assess our students? Two common reasons for assigning assessments include determining what students have learned and assigning grades, yet another purpose of assessments can include providing information about the effectiveness of instruction, both longstanding approaches and instructional innovations. In this seminar we will discuss both formative and summative assessments, as well as how one can use all forms of assessment to inform curricular change. Using examples from my research, we will discuss ways to integrate formative assessment into a course to provide feedback for the instructor as well as learning opportunities for students. We will explore an investigation in which I used a concept inventory to identify chemistry misconceptions held by students at the start of a biochemistry course, and then used the results of that assessment to make targeted instructional changes that succeeded in correcting those misconceptions. In another study, I helped develop an exam-level assessment that was used to evaluate student understanding of metabolic pathways; this provided evidence of systems thinking in student responses and illustrates ways to make assessments more accessible to all students. This assessment data can now serve as a baseline to evaluate future instructional changes in the biochemistry course. Through this seminar, we will see that all forms of assessment can be used to identify areas of instruction that can be improved upon, and that changes to instruction in response to assessments can be as small as a targeted clicker question or as large as redesigning a course. Regardless, instructional changes should be based on evidence from student assessments and continually evaluated for their efficacy through assessment of student learning.

Chem 263 Seminars in Chemical Biology: Mikayla Tan
2023-06-06 16:00 - 17:30 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

Jeffrey I. Zink Inorganic Chemistry Seminar Series: Wenyu Huang
2023-06-07 16:00 - 17:30 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States
Flyer: Prof. Wenyu Huang Flyer
Title: From Selective Hydrogenation to Polymer Upcycling: Implementation of Ordered Nanomaterials in Heterogeneous Catalysis
Abstract: Catalysis—the essential science for accelerating and directing chemical transformation—is the key to realizing environmentally friendly and economical processes for the conversion of fossil energy feedstocks. Catalysis is also the key to developing new technologies for converting alternative feedstocks, such as waste plastics, biomass, carbon dioxide, nitrogen, and water, to chemicals and fuels. The two grand challenges of heterogeneous catalysis, understanding mechanisms and dynamics of catalyzed reactions as well as the design and controlled synthesis of catalyst structures, require an atomic and electronic-level understanding of catalysts and catalytic processes. Due to their structural complexity, especially under reaction conditions, the catalytic active site and the molecule-catalyst interaction are often difficult to describe. This presentation will discuss our recent research on the synthesis, characterization, reaction study, and modeling of heterogeneous catalysts that are precisely synthesized at the atomic level using well-defined porous silica nanomaterials, intermetallic compounds, and metal-organic frameworks, which provide the means for meeting the two grand challenges of heterogeneous catalysis. This presentation will demonstrate that ordered nanomaterials could not only help the understanding of catalysis mechanisms but also reveal new catalytic phenomena.

Chem 218 Student Exit Seminar: Helen Huang
2023-06-08 12:00 - 13:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

Chem 218 Student Exit Seminar: Maya Segal
2023-06-15 12:00 - 13:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

Organic Graduate Symposium
2023-06-16 09:30 - 16:30 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

Chemistry and Biochemistry Commencement Ceremony
2023-06-17 16:30 - 17:45 | Court of Sciences
Join the Department of Chemistry and Biochemistry for our annual Commencement Ceremony honoring the accomplishments of graduating departmental students as they conclude this chapter of their academic journey.
Tickets are required for those attending in person. We will also be livestreaming the event with live captions activated. Please click below on Saturday, June 17 at 4:30pm to view the event.

Special Theoretical Chemistry Seminar by Prof. Sabre Kais
2023-07-12 13:00 - 14:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

Chem 218 Student Exit Seminar: Kathleen Chen
2023-08-17 12:00 - 13:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States
Kathleen Chen Flyer

Chem 247 Houk-Jung Organic Colloquium Special Seminar: Félix Calderón
2023-08-18 11:00 - 12:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

Jeffrey I. Zink Inorganic Chemistry Seminar Series: Sundargopal Ghosh
2023-09-20 16:00 - 17:30 | Collaboratory Yoo Seminar & Conference Hall YH4222
Title: “Coordination Chemistry of Diborane(4) and Diborane(6)”
Abstract: The fascinating aspect of metallaborane chemistry is that several classic organometallic complexes that defined fundamental structural and bonding paradigms are mimicked by many isoelectronic metallaborane analogues.[1] In this connection, diborane compounds not only mimics several classic organometallic compounds but also they have been extensively explored for the broad understanding of the chemical bonding and catalysis.[2] For example, we have recently synthesized and structurally characterized a bimetallic diborane(4) which mimics Cotton’s dimolybdenum–alkyne complex [{CpMo(CO)2}2C2H2].[3] Also, we have isolated the first classical diborane(5) [B2H5]-, in which the sp2-B center is stabilized by the electron donation from tantalum.[4] Very recently, we have developed an uncatalysed synthetic pathway to generate the doubly base stabilised symmetrical and unsymmetrical diborane(4) species from the thermolysis reaction of 2-mercaptopyridine with [BH3.THF]. The key results of this work will be described.

Jeffrey I. Zink Inorganic Chemistry Seminar Series: Titel Jurca
2023-09-27 16:00 - 17:30 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States
Title: “Building a Toolbox for Sustainable Synthesis and Catalysis”
Abstract: The presentation will focus on three of our current areas of interest:
Mechanochemical synthesis: by leveraging mechanochemical forces via vibratory ball milling or ultrasonic irradiation, we can expedite the synthesis of both conventional, and exotic Schiff base coordination complexes. Critically these reactions can be performed solvent-free or solvent-minimal, and facilitate the formation of target compounds in one-pot and one-step from multiple starting materials in minutes-to-hours compared to conventional multi-day, multi-step processes.
Silane-based reductions: using silanes, high-valent, mid d-block metal halides can be controllably reduced to highly reactive mid-valent synthons (e.g. MoCl3). The reactions are facile, and produce only H2 and recoverable chlorosilanes as byproduct. The resulting products are ideal starting points towards new precursors for ALD and CVD; enabling technologies for coatings, electronic materials, and heterogeneous catalysis.
Monolith-based nanocatalysts: controlled growth of nanocatalysts on contiguous Ni foams. Ni foams afford numerous advantages; among these include ease of handling and facile separability inherent to monolith systems, suitability for continuous flow catalysis, and self-stirring. The application of these materials towards catalytic hydrogenations will be discussed.

Dickerson Biochemistry Seminar
2023-09-29 15:30 - 16:30 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States
Introduction of Biochemistry Faculty to First Year Biochemistry Graduate Students

Physical Chemistry Seminar 228: Evgeny Pidko
2023-10-02 16:00 - 17:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States
Pidko Flyer
Title: Death and Life of Homogeneous Carbonyl Reduction Catalysts: Navigating Condition Space Towards Superior Catalytic Performance
Abstract: Catalytic hydrogenation chemistry offers a greener and more sustainable alternative to prevalent stoichiometric reduction methodologies in the production of high-value chemicals. In recent years, traditional Ru and Ir catalysts have been complemented by novel first-row transition metal catalysts due to their favorable sustainability, economics, and reduced toxicity. The practical implementation of such catalysts based on e.g. Fe or Mn is often hampered by their limited stability under the catalytic conditions. Understanding the catalytic and deactivation paths for such systems is key to tailoring their properties towards enhanced and sustained catalytic performance. In this lecture, I will discuss the importance and challenges of understanding the chemistry of catalyst deactivation for the development of practical catalytic technologies with the examples of our recent studies on Mn catalysis for selective reduction of carbonyl-containing compounds. While the performance of homogeneous catalysts is typically interpreted based on the molecular structures and electronic properties of the originating organometallic compounds, these catalyst systems are complex and multifunctional. Their behavior is influenced by a wide range of parameters, such as activation procedure, presence of promotors, solvent type, and selected conditions. Insights into the underlying mechanisms and their condition-dependencies can be obtained through a combination of operando spectroscopy, kinetic studies, and automated computational mechanistic analysis. This approach can help navigate this vast condition space and enhance the efficiency and lifespan of 3d metal-based catalyst systems.

Jeffrey I. Zink Inorganic Chemistry Seminar Series: Brandon Jolly and Yi Chen
2023-10-04 16:00 - 17:30 | Collaboratory Yoo Seminar & Conference Hall YH4222
Flyer: Brandon Jolly and Yi Chen Flyer
Speaker: Brandon Jolly
Title: Spatial Control in Multi-step, Multi-catalyst Organometallic Processes
Abstract: Spatial localization is one method in which biology manages its complex network of multi-step and/or multi-catalyst processes. For example, encapsulation of enzymes via compartmentalization allows for the efficient generation and utilization of intermediate species along a biochemical pathway. Much work has been devoted to applying compartmentalization for efficient in vitro enzyme cascades both theoretically and experimentally. However, only recently has attention been given to spatial localization in the context of organometallic catalysis experimentally, with no theoretical insights. Therefore, we developed a kinetic model to evaluate and understand the effect compartmentalization may have on a multi-step organometallic process, such as a typical catalytic cycle. A key design principle born out of this work is that compartmentalization is predicted to benefit organometalic catalysis if diffusion into/out of the compartment is kinetically comparable to, or slower than the catalytic cycle itself, which is tunable via compartment morphology. Next, we then set out to extend the concept of spatial localization in organometallics to multi-catalyst processes. Specifically, electrocatalytic CO2 reduction integrated to Pd catalyzed polyketone synthesis was chosen as a target multi-catalyst system that may benefit from spatial control. Ultimately, we demonstrate the generation and consumption of CO from CO2 reduction to co-polymerization with ethylene in one pot, with external control over %CO incorporation into the polymer via applied current, which is unattainable without spatial control.
Speaker: Yi Chen
Title: Generate Gradient in Electrochemical Microfluidic Systems to Investigate P. Aeruginosa Metabolic Regulation Kinetics on Single Cell Level
Abstract: Comprehending how bacterial metabolism adapts to environmental changes, like oxygen abundance variation, is important in microbial ecology and has potential applications in disease treatment and bacterial infection. Previous research primarily centered on the collective regulatory responses in bulk culture study while single-cell level understanding of bacterial regulation kinetics still remains a challenge. To address the challenge, we developed an electrochemical microfluidic system to generate microscopic oxygen and hydrogen peroxide concentration gradients, simulating the intricate micrometer-scale environments inhabited by bacteria. Particularly, we cultivated P. aeruginosa in the generated oxygen gradient and investigated its metabolic regulation kinetics on single-cell level, specifically with regard to the concentration of adenosine triphosphate (ATP), in response to environmental oxygen spatial variation and temporal oscillation.

Dickerson Biochemistry Seminar – Guillaume Chanfreau and Juli Feigon
2023-10-06 15:30 - 16:30 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

Physical Chemistry Seminar 228: Mitchio Okumura
2023-10-09 16:00 - 17:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States
Okumura Flyer
Title: Combs and Mirrors: Spectroscopic Studies of Radical Reactions Important in Air and Space
Abstract: Trace gas phase free radicals play a central role in the chemistry of Earth and planetary atmospheres, as well as the interstellar medium. Laboratory studies of their spectroscopy, reaction dynamics and kinetics are important for accurate modeling of these environments. Experiments require high sensitivity, time resolution, and specificity to detect these reactive intermediates. We have pursued advances in spectroscopic techniques using optical cavities and optical frequency combs to detect free radicals in the Mid-Infrared by direct absorption. I will discuss several examples of cavity ringdown, direct frequency comb cavity-enhanced spectroscopy, and Vernier comb spectroscopy and their applications to atmospheric kinetics. In addition, I will present experiments using Uniform supersonic flows and LIF detection reveal new dynamical effects in low temperature radical kinetics.

John D. & Edith Roberts Lecture - Prof. Soumitra Athavale
2023-10-10 16:00 - 17:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States
Title: TBD
Abstract: TBD
Flyer Pending

John D. & Edith M. Roberts Lecture - Soumitra Athavale
2023-10-10 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222
Roberts Lecture Flyer

Jeffrey I. Zink Inorganic Chemistry Seminar Series: Timothy Johnstone
2023-10-11 16:00 - 17:30 | Collaboratory Yoo Seminar & Conference Hall YH4222
Prof. Timothy Johnstone Flyer
Title:“Synthesis, Isolation, and Exploration of the Chemistry of Kinetically-Stabilized Pnictine Oxides”
Abstract: The light pnictine oxides R 3 NO, R 3 PO, and R 3 AsO comprise a well-characterized class of monomeric molecules with a tetrahedral geometry about the pnictogen center. In contrast, the preparation of the corresponding Sb and Bi species has long proved challenging. For the heavier pnictogens, reduced orbital overlap with oxygen increases charge separation, which in turn increases the electrophilicity of the pnictogen and the nucleophilicity of the oxygen. Furthermore, the heavier pnictogens have an increased propensity to expand their coordination spheres. Consequently, stibine oxides and bismuthine oxides occur as oligomeric/polymeric materials. We have recently employed a kinetic stabilization strategy to isolate the first example of an unperturbed monomeric stibine oxide. We have examined the electronic structure of the newly isolated stiboryl functional group using a variety of physical and theoretical techniques. These investigations have guided our exploration of the reactivity of this previously inaccessible unsaturated (heavy pnictogen)–oxygen bond

Houk-Jung Organic Colloquium 247: Steven D. Townsend
2023-10-12 16:00 - 17:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States
Townsend Flyer
Title: Preventing Premature Birth and Breaking Strong Bonds with Carbohydrates
Abstract: Abstract: Carbohydrates are the most abundant organic molecules on earth and are critical to a myriad of biological processes. The Vanderbilt Laboratory for Glycoscience uses a blend of synthetic organic chemistry and microbiology to elucidate the biological roles of carbohydrates, with a foci on advances in chemical synthesis and learning new mechanistic concepts. Our discussion will be divided into two categories: (1) the synthesis of structurally and biologically compelling complex carbohydrates, and (2) application of the host defense properties of human milk.

Dickerson Biochemistry Seminar – David Eisenberg and Bill Gelbart
2023-10-13 15:30 - 16:30 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States
