UCLA

Dickerson Biochemistry Seminar Series - Rob Clubb and Bill Gelbart
2024-11-15 15:30 - 17:00 (America/Los_Angeles) | Collaboratory Yoo Seminar & Conference Hall YH4222

Bristol-Myers Squibb Lecture
2024-11-14 15:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222
BMS Seminar Flyer

Jeffrey I. Zink Inorganic Chemistry Seminar Series – Prof. Ellen Matson
2024-11-13 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222
Flyer: Prof. Ellen M. Matson Flyer
Title: Structure-function Relationships that Dictate Proton Coupled Electron Transfer at the Surfaces of Polyoxometalate Clusters
Abstract:While the dynamics of proton- and electron-transfer at metal oxides have been studied extensively in the field of electrochemical energy storage, researchers have only very recently begun to understand how these process play out on molecular length scales and in the presence of small-molecule substrates. The latter is notable, considering that redox-active metal oxides are widely used in thermal and electrochemical catalytic processes. Further advances in the effective use of metal oxides in electrochemical catalysis will require improved understanding of elementary charge-transfer reaction mechanisms. Our research team has been studying the interfacial reactivity of reducible metal oxides using atomically precise, polyoxometalate clusters as models for extended materials. Polyoxometalates (POMs) consist of three of more redox-active transition metal oxyanions that are linked together by bridging oxide units to form three dimensional structures. These self-assembled clusters are well-positioned to provide insight into the surface chemistry of reducible metal oxides. This talk will focus on the synthesis and characterization of reduced POMs, which have provided our research group with opportunities to investigate factors that dictate mechanisms of H-atom uptake and transfer at metal oxide surfaces. Collectively, our studies inform our understanding of proton-dependent reactivity of metal oxide surfaces, toward the design of materials capable of converting chemical pollutants into energy-rich fuels.

Dickerson Biochemistry Seminar Series - Joe Loo and Stefan Petrovic
2024-11-08 15:30 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Saul Winstein Lecture: Prof. Matthew Sigman
2024-11-07 16:00 - 17:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

Jeffrey I. Zink Inorganic Chemistry Seminar Series – Prof. Samanvaya Srivastava
2024-11-06 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222
Flyer: Prof. Samanvaya Srivastava Flyer
Title: Complex Coacervate Microemulsions
Abstract: This presentation will discuss our progress in creating stable membraneless water-water emulsions comprising complex coacervate microdroplets. Complex coacervation is a liquid-liquid phase separation phenomenon driven by the electrostatic association of oppositely charged multivalent macromolecules in water, creating coacervate microdroplets enriched with charged moieties. These aqueous membraneless microdroplets possess numerous attributes desired in colloidal reactors and protocell models. However, the membraneless coacervate-water interface that facilitates many of the bio(techno)logical functions of the coacervate microdroplets also promotes their coalescence, resulting in rapid coarsening and sedimentation. We will discuss our recently discovered strategy to stabilize complex coacervate microdroplets without introducing membranous sheaths around the droplets by utilizing the assembly of anionic comb polyelectrolytes at the water(coacervate)-water interface. We will demonstrate the tunability of microdroplet size, its months-long stability, and its ability to withstand high ionic strength environments. Selective sequestration of charged (bio)molecules (proteins and enzymes) into the crowded environments of stabilized coacervate microdroplets will be argued to affect a significant (up to 10-fold) and sustained acceleration of enzyme-mediated bioreactions. Aided by the low cost of the constituent polymers and the simplicity of the formulations, we will argue that the stabilized coacervate emulsions serve as efficient enzyme-encapsulants in economical, large-scale flow bioreactors.

Physical Chemistry Seminar 228: Prof. Anna Krylov
2024-11-04 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Chem 248 Organic Chemistry Student Seminar: Allison Clark
2024-11-04 15:00 - 16:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Dickerson Biochemistry Seminar Series – Steve Clarke and Carla Koehler
2024-11-01 15:30 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Houk-Jung Organic Colloquium: Prof. Grace Han
2024-10-31 16:00 - 17:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

Inorganic Chemistry Student Exit Talk: Yessica Nelson
2024-10-30 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222
Flyer: Yessica Nelson Student Exit Talk Flyer
Title: Tailoring Boron Clusters: The Impact of Vertex-Differentiated closo-Dodecaborates in Emerging Applications
Abstract: My presentation will highlight recent advancements in the vertex-precise manipulation of polyhedral boron clusters. Specifically, our work centers on developing methods to selectively functionalize the [B₁₂H₁₂]²⁻ cluster, a quintessential three-dimensional aromatic boron-based system, with high precision at individual boron vertices. I will demonstrate how multiple orthogonal strategies can be applied to precisely position various reactive functional groups on this cluster, enabling the creation of novel molecules that serve as key building blocks for extended solids, polymers, and materials with applications ranging from energy storage systems to biologically relevant imaging agents. Our approach allows the functionalization of the –OH, –SH, and –SeH groups as versatile synthetic handles. In some cases, these modifications can be achieved electrochemically, minimizing waste and simplifying purification processes.

Physical Chemistry Seminar 228: Prof. Matthew Sheldon
2024-10-28 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Chem 248 Organic Chemistry Student Seminar: Ryan Lai
2024-10-28 15:00 - 16:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Distinguished Lecture Series/Donald J. Cram Lecture - Prof. David Leigh
2024-10-24 16:00 - 17:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

Jeffrey I. Zink Inorganic Chemistry Seminar Series – Prof. Jack Norton
2024-10-23 16:00 - 17:30 | Collaboratory Yoo Seminar & Conference Hall YH4222
Flyer: Prof. Jack Norton Flyer
Title: Applications of Catalytic H• Transfer from H2
Abstract: Transition-metal hydride complexes with en-he bonds stronger than 56 kcal mol’ can often be generated from hydrogen, and may thus be able to catalyze the transfer of H from that gas. Hydrides with unusually weak M-H bonds, such as HV(CO),(dppe), can carry out stoichiometric cyclizations of enamines that contain a remote C=C, converting them to pyrrolidines. The reaction of a Co(Il) salen complex with an olefin in the presence of NaBH, and ‘BuOOH also appears to form a radical by H• transfer, and these radicals can be trapped by TEMPO. The photochemical oxidation of these TEMPO adducts to carbocations (Knowles, Angew. Chem. Int. Ed. 2016, 55, 9969) allows the interception of these cations by many different nucleophiles, giving Markovnikov hydrofunctionalization products. A particularly valuable application of this reaction is in the net hydrofluorination of olefins.

Inorganic Chemistry Student Exit Talk: Shuaijing Du
2024-10-22 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222
Shuaijing Du of the Duan Research Group
Flyer: Shuaijing Du Student Exit Talk Flyer
Title: Introducing Chirality into Hybrid Superlattices
Abstract: I will present recent results on two different projects, with the common theme of introducing chirality into hybrid superlattices. 1: Modular assembly of a library of hybrid superlattices. Hybrid superlattices, composed of two-dimensional atomic crystals (2DACs) and self-assembled molecular layers, provide a platform for synergizing the rich physical properties of solid-state 2DACs with customizable molecular functionalities. In this project, we develop a modular electrostatic co-assembly approach for synthesizing over 50 hybrid superlattices from a diverse set of 2DACs and molecular building blocks. We demonstrate that in addition to amines, chiral amino acids and coordination complexes can also assemble with exfoliated MoS2 into hybrid superlattices, incorporating optical chirality into the hybrid superlattices. 2: Construction of chiral hybrid superlattices with monoatomic platinum layers. Compared with layered materials such as graphite and transitional metal dichalcogenides with highly anisotropic in-plane covalent bonds, freestanding metallic two-dimensional (2D) films with atomic thickness are intrinsically more difficult to achieve. This study introduces stabilized monoatomic Pt layers by forming a chiral hybrid superlattice structure with self-assembled chiral carboxylic acid ligand layers. Circular dichroism (CD) spectra of the chiral hybrid superlattices show clear CD signals distinct from the chiral carboxylic acids themselves.

UCLA SPACE Institute: Chemistry and Materials for Space Science and Technology
2024-10-18 13:00 - 19:30 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

UCLA Boehringer-Ingelheim Lecture
2024-10-17 15:00 - 17:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States

Inorganic Chemistry Student Exit Talk: Shiyun Lin, Yin Pok George Wong, and Hootan Roshandel
2024-10-16 16:00 - 18:00 | Collaboratory Yoo Seminar & Conference Hall YH4222
Flyer: Shiyun Lin, George Wong, and Hootan Roshandel Flyer
Shiyun Lin
Title: Multistate Catalysis: Ferrocene Aluminum Compound for Versatile Polymerization and Sustainable Polycarbonates
Abstract: Nature has developed an intricate mechanism through polymerase enzymes to control polymerization with monomer-level precision. However, this system is restricted to a limited range of monomers. In contrast, synthetic chemistry offers the potential to create an almost infinite variety of monomers for diverse materials, though synthetic catalysts typically lack the precise monomer selectivity seen in natural systems. In this work, we present a ferrocene aluminum compound, (salfan-H2)Al(OiPr) (salfan-H2 = 1,1’-di(2,4-bis-tert-butyl-salicylamino)ferrocene), which has four tunable redox and protonation states that demonstrate orthogonal reactivity toward different monomers. This system exhibits switchable ring-opening polymerization activity, enabling the synthesis of novel copolymers, including a ABCD tetrablock copolymers. We also explore its reactivity with CO2 in polycarbonate synthesis through biphasic reactions, achieving selective monomer incorporation and demonstrating the potential for closed-loop polycarbonate polymerization and depolymerization.
Yin Pok George Wong
Title: Accelerating Polymerization Catalyst Discovery with Data and Network Science
Abstract: In this talk, I will present the work on using various learning algorithms to predict and discover polymerization catalysts. As an example, we have applied a supervised classifier to predict palladium catalysts for producing non-alternating polyketones via the copolymerization of carbon monoxide and ethylene. Currently, reported examples are limited to using phosphine-sulfonate and diphosphazane monoxide supporting ligands. With a data-driven workflow, we were able to discover three new classes of supporting liagnds (phosphine-phenolate, bisphosphine monoxide and phosphonic diamide-phosphine) capable of achieving the palladium-catalyzed synthesis of non-alternating polyketones with a lower CO content than known catalysts. In addition, I will be introducing the concept of catalyst repurposing by showcasing ongoing work in building a bipartite network and using link prediction to create a recommender system that can rank existing catalysts for reactions which have not been tested before.
Hootan Roshandel
Title: Ferrocene Charcuterie: Ferrocene-Based Compounds for Polymerization and Quantum Applications
Abstract: This talk will contain a variety of topics ranging from the development of 3D visualization and augmented reality tools for applications in scientific communication and outreach, to the exploration of the reactivity of ferrocene-based ring opening polymerization catalysts for synthesis of biocompatible polymers, and to the role of ferrocene-based Yb(III) complexes for quantum sensing applications. Along the way, we will discuss the use of machine learning tools for the prediction of chemical activity of a series of redox-active catalysts, highlight the unexplored role of metal-ligand cooperativity in Ti and Zr amino ferrocene-based ligands, and utilization of unconventional nuclear magnetic resonance experiments for characterization of the ferrocene-based compounds for in situ structural and mechanistic studies.

Physical Chemistry Seminar 228: Prof. Jeff Sakamoto
2024-10-14 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Chem 248 Organic Chemistry Student Seminar: Cameron Scott Jones
2024-10-14 15:00 - 16:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Dickerson Biochemistry Seminar Series - David Eisenberg and Mike Lawson
2024-10-11 15:30 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

UCLA Amgen Lecture
2024-10-10 16:00 - 17:00 | Mani L. Bhaumik Centennial Collaboratory, 607 Charles E. Young Dr., East, Los Angeles, CA, 90095, United States
https://tinyurl.com/uclaamgen

Jeffrey I. Zink Inorganic Chemistry Seminar Series – Prof. Jonathan Rittle
2024-10-09 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222
Flyer: Prof. Jonathan Rittle Flyer
Title: Discovery of Manganese-Dependent Monooxygenases
Abstract: The aerobic oxidation of carbon–hydrogen (C–H) bonds in biology is currently known to be accomplished by a limited set of cofactors that largely include heme, nonheme iron, and copper. While manganese cofactors perform difficult oxidation reactions, including water oxidation within Photosystem II, they are generally not known to be used for C–H bond oxidation, and those that do catalyze this important reaction display highly limited intrinsic reactivity. In this seminar, I will describe a handful of homologous enzymes that either require manganese, iron, or mixtures thereof to functionalize strong, aliphatic C–H bonds (BDE = 100 kcal/mol). Structural and spectroscopic studies on these systems reveal redox-active, bimetallic active sites that represent the locus of O2 activation and substrate coordination. Our combined results dramatically expand the known reactivity of biological manganese–containing cofactors, and suggests that many uncharacterized (or mischaracterized) monooxygenases may similarly utilize manganese to perform crucial oxidative biochemical tasks.

Physical Chemistry Seminar 228: Prof. Connor Bischak
2024-10-07 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Dickerson Biochemistry Seminar Series - Profs Guillaume Chanfreau and Juli Feigon
2024-10-04 15:30 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Jeffrey I. Zink Inorganic Chemistry Seminar Series – Dr. David Kwabi
2024-10-02 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222
Flyer: Dr. David Kwabi Flyer
Title: Designing Organic Redox-Flow Batteries for Energy Storage and CO2 Capture
Abstract: Avoiding the most severe consequences of climate change can be achieved by increasing the pace at which carbon-free/renewable power is adopted to replace fossil fuels, capturing and permanently sequestering CO2 away from the atmosphere, or both. Large-scale implementation of both approaches is primarily challenged by technological barriers. Because renewable (e.g. solar and wind) power is intermittently available, its more extensive deployment on the grid requires low-cost storage technologies. CO2 capture systems must likewise be inexpensive and energy-efficient while enabling high rates of CO2 uptake from point and distributed sources. Electrochemical devices with organic active materials are promising candidates for both tasks. They can store electrical energy in the form of batteries and enable selective separation processes – in the latter case, without the Carnot efficiency limit that conventional thermal separation methods face. In this talk, I will discuss our group’s recent progress in using numerical modeling and statistical inference techniques to understand the kinetics of charge carrier conversion and decomposition in organic redox-flow batteries for grid-scale energy storage. I will also discuss how these techniques can be extended to understanding the performance limits of electrochemical CO2 capture scheme featuring reversible pH swings created by proton-coupled electron transfer in aqueous electrolytes.

Physical Chemistry Seminar 228: Prof. Joseph Francisco
2024-09-30 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Dickerson Biochemistry Seminar Series - Welcome Seminar
2024-09-27 15:30 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222

Houk-Jung Organic Colloquium Special Seminar - Prof. Weixin Tang
2024-09-19 16:00 - 17:00 | Collaboratory Yoo Seminar & Conference Hall YH4222
