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Full-Text Articles in Chemistry

Methods For Increasing The Electron Richness Of Iron Tricarbonyl Diimine Complexes, Francesca Lombardi, Joseph Maher, Sean Peloquin Apr 2023

Methods For Increasing The Electron Richness Of Iron Tricarbonyl Diimine Complexes, Francesca Lombardi, Joseph Maher, Sean Peloquin

Chemistry & Biochemistry Student Scholarship

Francesca Lombardi ’24, Major: Chemistry

Joseph Maher ’25, Major: Chemistry

Sean Peloquin ’26, Major: Biochemistry

Faculty Mentor: Dr. Maria Carroll, Chemistry and Biochemistry

The goal of our research is to synthesize new iron complexes that can reduce carbon dioxide. Increasing the electron richness of iron tricarbonyl diimine complexes, which have been synthesized previously in the Carroll research group, will increase the likelihood of a reaction with carbon dioxide occurring. We have taken two approaches to changing the electron density in the complexes. First, we reacted the complex Fe((CF3)2ArDABMe)(CO)¬3 with the reducing agent potassium on graphite, in order to reduce either …


Toward The Design, Synthesis, And Characterization Of Abiotic Coiled-Coil Peptides Via Solid-Phase Copper-Catalyzed Azide-Alkyne Cycloaddition (Sp-Cuaac) Click Reaction For The Preparation Of Controlled Self-Assembly Molecular Building Block, Liaquat Ali Apr 2023

Toward The Design, Synthesis, And Characterization Of Abiotic Coiled-Coil Peptides Via Solid-Phase Copper-Catalyzed Azide-Alkyne Cycloaddition (Sp-Cuaac) Click Reaction For The Preparation Of Controlled Self-Assembly Molecular Building Block, Liaquat Ali

Chemistry Theses

The production of cutting-edge materials, the development of novel medications, drug delivery systems, technological advancements, and biosynthesizing all depend on molecular building blocks. Proteins are required for the creation of intricate, well-organized structures, and coiled-coil protein domains are vital subunits for the oligomerization of protein complexes, gene expression, and the structural components of biological materials. The numerous interactions between a wide variety of amino acids make it difficult to assemble protein complexes with a particular shape. In the current study, we successfully designed and synthesized four different 32-residue peptides, each of which had two modified amino azide residues. These peptides …


Surface Characterization Of Mixed-Mode Adsorbents Using Bet C-Constant Energy Scale, Dinah C. Lee Apr 2023

Surface Characterization Of Mixed-Mode Adsorbents Using Bet C-Constant Energy Scale, Dinah C. Lee

Seton Hall University Dissertations and Theses (ETDs)

Mixed-mode chromatography is a chromatographic method in which solutes interact with stationary phase through more than one interaction mode or mechanism. It is because of these multiple complex interactions, which makes it difficult to predict chromatographic behavior of analytes on Mixed-mode columns. In order to fully understand the retention mechanisms on Mixed-mode columns, the packing material properties must be well characterized since each characteristic may contribute to the overall chromatographic performance of the column. Many non-chromatographic and chromatographic techniques are available to characterize and compare Mixed-mode columns in terms of their interaction abilities, retentivity, surface chemistry, chemical properties and geometry. …


Ultrafast Dynamics Of Photosynthetic Light Harvesting: Strategies For Acclimation Across Organisms, Olivia C. Fiebig, Dvir Harris, Dihao Wang, Madeline P. Hoffmann, Gabriela S. Schlau-Cohen Apr 2023

Ultrafast Dynamics Of Photosynthetic Light Harvesting: Strategies For Acclimation Across Organisms, Olivia C. Fiebig, Dvir Harris, Dihao Wang, Madeline P. Hoffmann, Gabriela S. Schlau-Cohen

Chemistry: Faculty Publications

Photosynthetic light harvesting exhibits near-unity quantum efficiency. The high efficiency is achieved through a series of energy and charge transfer steps within a network of pigment-containing proteins. Remarkably, high efficiency is conserved across many organisms despite differences in the protein structures and organization that allow each organism to respond to its own biological niche and the stressors within. In this review, we highlight recent progress toward understanding how organisms maintain optimal light-harvesting ability by acclimating to their environment. First, we review the building blocks of photosynthetic light harvesting, energy transfer, and time-resolved spectroscopic techniques. Then, we explore how three classes …


Transannular Functionalization Of Multiple C(Sp3)-H Bonds Of Tropane Via An Alkene-Bridged Palladium(I) Dimer, Ellen Y. Aguilera, En Chih Liu, Scott M. Thullen, Melanie S. Sanford Apr 2023

Transannular Functionalization Of Multiple C(Sp3)-H Bonds Of Tropane Via An Alkene-Bridged Palladium(I) Dimer, Ellen Y. Aguilera, En Chih Liu, Scott M. Thullen, Melanie S. Sanford

Chemistry Faculty Research & Creative Works

This Communication describes the Pd-catalyzed C(sp3)-H functionalization of a tropane derivative to generate products with functionalization at two (β/γ) or three (β/γ/β) different sites on the alicyclic amine core. These reactions proceed via an initial dehydrogenation to generate an alkene product that can react further to form a Pd(I) alkene-bridged dimer. Functionalization of this dimer affords β/γ/β-functionalized allylic arylation and allylic acetoxylation products.


The Influence Of Diamine Curing Additives On The Network Architecture Of Phthalonitrile Thermosetting Polymers, Tyler J. Richardson Apr 2023

The Influence Of Diamine Curing Additives On The Network Architecture Of Phthalonitrile Thermosetting Polymers, Tyler J. Richardson

Dissertations

Phthalonitrile monomers undergo diamine-promoted polymerization by a complex reaction mechanism involving two competitive cure pathways, forming two primary network architectures: linear polyisoindoline chains and branched triazine crosslinks. The influence of the diamine curing additive on the polymerization pathway, and the influence of the resulting network architectures on cured network properties, have not been adequately explored within the phthalonitrile field. Two structurally different diamine curing additives, bis[4-(3-aminophenoxy)phenyl] sulfone (mBAPS) and 1,3-phenylenebis((4-(4-aminophenoxy)phenyl)methanone) (AEK-134), were studied for the polymerization of resorcinol phenylphosphate phthalonitrile (RPPhPN), where the influence of diamine structure and concentration on the polymerization behavior, network architecture, and bulk thermal and thermomechanical …


Characterization Of Shinella 6-Hydroxy-(L)-Nicotine Oxidase (6hlno-Se), Kaitrin Funckes Apr 2023

Characterization Of Shinella 6-Hydroxy-(L)-Nicotine Oxidase (6hlno-Se), Kaitrin Funckes

Honors Theses

6-hydroxy-(L)-nicotine oxidase, isolated from the organism Shinella sp. HZN7 (6HLNO-SE), is an enzyme that during the catabolism of nicotine catalyzes the oxidation of (S)-6-hydroxynicotine to 6-hydroxypseudeooxynicotine. This enzyme is a member of the monoamine oxidase (MAO) structural family of flavoproteins, which contain a highly conserved FAD-binding domain. Within the binding domain is a conserved lysine residue that can be traced throughout evolutionary history in this family. 6HLNO isolated from Arthrobacter nicotinovorans serves as a model enzyme for the one isolated from Shinella as both catalyze the same reaction in this biochemical pathway and much has been studied about the Arthrobacter …


Synthesis And Characterization Of Some Disubstituted Cyclopentadienyl Rhenium Complexes As Potential Candidates In Semiconductive Materials, Chloe Vernon Apr 2023

Synthesis And Characterization Of Some Disubstituted Cyclopentadienyl Rhenium Complexes As Potential Candidates In Semiconductive Materials, Chloe Vernon

Liberty University Research Week

Undergraduate

Three Minute Thesis


Thp-1 Monocytes As A Model For The Characterization Of Potential Agents For Hypersensitization Observed In Ags?, Colin Baker Apr 2023

Thp-1 Monocytes As A Model For The Characterization Of Potential Agents For Hypersensitization Observed In Ags?, Colin Baker

Liberty University Research Week

Undergraduate

Three Minute Thesis


Incorporation Of Thiophenes And Benzothiophenes Into Novel Pi-Extended Dibenzophosphole Systems, Joshua Kim, Conner Schell Apr 2023

Incorporation Of Thiophenes And Benzothiophenes Into Novel Pi-Extended Dibenzophosphole Systems, Joshua Kim, Conner Schell

Campus Research Month

Dibenzophospholes are molecules with extended pi conjugation. This project aims to incorporate thiophenes and benzothiophenes into dibenzophosphole systems by using 2-bromothiophene, 2-bromobenzothiophene, and 3-bromobenzothiophene as starting materials. An ethyne intermediate is created via the Sonagashira reaction, which is further reacted to form the novel dibenzophosphole system. The ultimate goal is to fuse the newly incorporated functional groups, creating an even greater degree of conjugation.


Bacterial-Mediated Photocatalytic Organic Oxidation, Peter J. Pellegrinelli Apr 2023

Bacterial-Mediated Photocatalytic Organic Oxidation, Peter J. Pellegrinelli

Theses and Dissertations

Bacteria, though well-known and widespread in scientific application, have plenty more opportunity to grow in the field of organic synthesis. The primary objective of this project was to apply the use of bioluminescent bacteria in an organic photoredox reaction intending to use the bacteria as a renewable source of light. This sustainable method, as opposed to high wattage bulbs, paves a green pathway for organic photocatalytic reactions. Using bioluminescent E. coli, the focus was on performing organic oxidation reactions with a recyclable photocatalyst. When using bacteria in conjunction with chemicals like nitromethane, it was an obstacle to keep the E. …


Computational Study Of The Rotational Barrier In Indole Derivatives, Javaughn Martinez Apr 2023

Computational Study Of The Rotational Barrier In Indole Derivatives, Javaughn Martinez

Honors Theses

The purpose of this computational study is to understand the rotational barrier in indole derivatives, leading to stereoisomers, specifically atropisomers, which will impact the research direction focused on the development of a porphyrin hosts in Professor Starnes’s group. The Starnes research group is working to synthesize a porphyrin host that can function as a sensor or to remove harmful and deleterious anions such as phosphate and nitrates (Busschaert, et al, 2015). We will utilize the data provided to understand the required energy to restrict a rotation around the indole-benzene bond. To do so, the indole derivatives will be studied using …


Computational Design And Molecular Modeling Of Morphine Derivatives For Preferential Binding In Inflamed Tissue, Makena Augenstein, Nayiri Alexander, Matthew Gartner Apr 2023

Computational Design And Molecular Modeling Of Morphine Derivatives For Preferential Binding In Inflamed Tissue, Makena Augenstein, Nayiri Alexander, Matthew Gartner

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The opioid epidemic has impacted over 10 million Americans in 2019. Opioids, like morphine, bind non-selectively in both peripheral tissue, leading to effective pain relief, and central tissue, resulting in dangerous side effects and addiction. The inflamed conditions of injured tissues have a lower pH (pH = 6–6.5) environment than healthy tissue (pH = 7.4). We aim to design a morphine derivative that binds selectively within inflamed tissue using molecular extension and dissection techniques. Morphine binds to the μ-opioid receptor (MOR) when the biochemically active amine group is protonated. Fluorination of a β-carbon from the tertiary amine group led to …


Hplc And Cms Analysis Of Clomipramine Metabolism: A Multi-Drug Study, Tess E. Buescher, Tu Khiem Ho, Kyler Ford Apr 2023

Hplc And Cms Analysis Of Clomipramine Metabolism: A Multi-Drug Study, Tess E. Buescher, Tu Khiem Ho, Kyler Ford

Research & Creative Achievement Day

Daily use of multiple medications is commonplace for many Americans. While pharmacists monitor prescriptions for drug interactions, consumers rarely check the possible side effects when using an over-the-counter product. In this fictional case study, Sam is prescribed clomipramine and ciprofloxacin, while also taking Tylenol PM. All three medications are orally administered, and drug metabolism is catalyzed in the liver by cytochrome P450 enzymes (CYP450). CYP isoenzymes CYP1A2, CYP3A4 and CYP2C19 are responsible for clomipramine metabolism and formation of major bioactive metabolite desmethylclomipramine, while CYP2D6 hydroxylates clomipramine and metabolite into hydroxyclomipramine and hydroxydesmethylclomipramine, respectively. Multi-drug use can inhibit or induce metabolic …


Exploration Of Known Disease-Causing Vrk1 Mutants, Madelyn M. Degenhardt Apr 2023

Exploration Of Known Disease-Causing Vrk1 Mutants, Madelyn M. Degenhardt

Research & Creative Achievement Day

VRK1 is a vaccinia-related serine/threonine kinase that contributes to the regulation of cell proliferation. Point mutations within the VRK1 sequence are associated with a variety of complex neurodegenerative disorders which previous research suggests are due to changes in kinase activity and/or structure and stability. Point mutations seen with VRK1 may affect how a tail on the C-terminus of the protein interacts with the protein's active site, possibly altering the ability of the protein to bind to specific substrates.  This study looked specifically at the point mutation D263G and its effect on protein stability and ability to bind substrates at its …


Development Of New Synthetic Routes For Ebselen In Pursuit Of The First Synthesis Of Ebtellur, Elijah Kellner, Creed Poppler Apr 2023

Development Of New Synthetic Routes For Ebselen In Pursuit Of The First Synthesis Of Ebtellur, Elijah Kellner, Creed Poppler

Research & Creative Achievement Day

Ebselen, N-phenyl-1,2-benzoisoselenazol-3(2H)-one, an established anti-oxidant and cytoprotective agent, has been assessed for an array of pharmaceutical applications in treating a multitude of disorders and maladies. It has further been identified as an anti-microbial and anti-viral agent against multiple infectious agents and has even been FDA-approved for a variety of these applications. While ebselen has captured pharmaceutical interest, its tellurium analogue, ebtellur, has yet to be successfully obtained, and in only one case was an attempt to obtain ebtellur reported. We have developed multiple new synthetic routes specifically targeting the first synthesis of ebtellur and discuss the viability of each pathway …


Utilizing Macroinvertebrate Communities And Chloride Levels To Evaluate Water Quality In Three Streams Near Winona, Minnesota, Amelia Engman, Izabella Setla Apr 2023

Utilizing Macroinvertebrate Communities And Chloride Levels To Evaluate Water Quality In Three Streams Near Winona, Minnesota, Amelia Engman, Izabella Setla

Research & Creative Achievement Day

Certain water quality and chloride levels are ideal for specific macroinvertebrate species. This study evaluates the water quality of three streams in and around Winona, Minnesota, using the macroinvertebrate communities present and chloride levels as indicators. Three upstream samples were taken and thoroughly examined at three different locations: Garvin Brook, Gilmore Creek, and Pleasant Valley Creek. During the snowmelt season, four sets of upstream and one set of downstream water samples were taken from each. The samples were analyzed using a Vernier chloride ion-selective electrode. The Izaak Walton League of America's Save Our Streams invertebrate classification system was used to …


Synthesis Of Activated Carbon From Spent Coffee Beans, Alyssa Priebe, Jennifer Zemke Apr 2023

Synthesis Of Activated Carbon From Spent Coffee Beans, Alyssa Priebe, Jennifer Zemke

Research & Creative Achievement Day

Activated carbon is a material that is used in various industries. An important way that activated carbon is used, is to remove impurities and contaminants from water. Activated carbon is used to filter out odors and pollutants such as organic compounds by adsorbing and trapping these molecules within the structure of the carbon. The goal of this research is to synthesize activated carbon from spent coffee grounds. To this end, we are developing and tuning a protocol for the synthesis of activated carbon via a Microwave-Assisted Reaction System (MARS-TA). Variables investigated in this study are the amount of phosphoric acid …


Temperature Dependent Esterification Of Free Fatty Acids In The Presence Of Triglycerides, Megan Mccoy, Margaret Tyler Apr 2023

Temperature Dependent Esterification Of Free Fatty Acids In The Presence Of Triglycerides, Megan Mccoy, Margaret Tyler

Liberty University Research Week

Undergraduate

Basic


Synthesis And Characterization Of Double Cross-Linked Pvpms Aerogels, Olivia B. Zill Apr 2023

Synthesis And Characterization Of Double Cross-Linked Pvpms Aerogels, Olivia B. Zill

Research & Creative Achievement Day

Aerogels have been rising to the surface as a material of interest for many practical applications. Aerogels are classified as "dried gels with a very high relative pore volume".1 The practical applications of aerogels include thermal insulators, electrical conductors, sensors, as well as optical applications and more.2–5 Aerogels are typically created through supercritical drying, in which the liquid in a sol-gel is turned into gas without destroying the structure of the gel. However this process requires high pressures and temperatures and the solvents used are highly flammable and unsafe at these conditions.6 The purpose of this research experiment is to …


Using 3d Printing To Illustrate Protein Modularity And Dynamics, Joanna M. Dinesen Apr 2023

Using 3d Printing To Illustrate Protein Modularity And Dynamics, Joanna M. Dinesen

Research & Creative Achievement Day

Many important enzymes are part of multi-subunit complexes that involve complex movements and interactions that are difficult to visualize via traditional 2-dimensional diagrams or in visualization software. Physical, 3-dimensional models are an especially effective way to illustrate abstract concepts within the curriculum, including about protein dynamics, subunit functions, pathway architectures, and the nature of protein-protein interactions. The usage of physical models in the classroom has been successful when teaching concepts such as enzyme catalysis and protein refolding, quantized by increased exam scores and positive student feedback. Here, we present work done to 3D print publicly available protein structures of the …


Student Laboratory For Synthesis And Characterization Of Proton Exchange Membranes, Christiana Hoyt Apr 2023

Student Laboratory For Synthesis And Characterization Of Proton Exchange Membranes, Christiana Hoyt

Research & Creative Achievement Day

The primary goal of this research was to improve the current Proton Exchange Membrane (PEM) Synthesis and Characterization laboratory exercise for CHEM 411-Synthesis and Characterization of Materials. Intended improvements to this lab included measuring conductivity of the PEM by finding the best procedure for creating the conductivity cell through both research and experiments in order to add electrochemical impedance spectroscopy in the characterizations for the lab. Commercial membranes, such as Nafion, have multiple issues: high cost, high methanol permeability, poor function at elevated temperatures and at low humidity being some of them. Using PEEK to synthesize PEMs can be used …


Degradation Of Ovulation Inhibitor Estrogens Using Hplc Chromatography, Jenna Holst Apr 2023

Degradation Of Ovulation Inhibitor Estrogens Using Hplc Chromatography, Jenna Holst

Research & Creative Achievement Day

In recent years, there has been a rise in observed intersex aquatic species along with a rise of reproductive issues in humans. This has been linked to the endocrine disrupting properties of over 200 chemicals that have estrogenic activity and persist in aquatic environments. The focus of our research is the estrogens that are used in hormonal birth control as ovulation inhibitors. Between 2015-2017, 14% of US women aged 15-49 were using hormonal birth control. According to a study published in 2002, three estrogens that are used in hormonal birth controls as ovulation inhibitors, 17α-ethynyl estradiol, mestranol, and 19-norethisterone, occur …


Purification And Characterization Of Vrk2 For Further Research, Steven Richter Apr 2023

Purification And Characterization Of Vrk2 For Further Research, Steven Richter

Research & Creative Achievement Day

Kinases represent a vast and varied group of proteins, having more than 500 members in human beings alone. They have been found to be involved in various signal transduction pathways, ranging from embryonic development to apoptosis. The vaccinia-related kinases (VRKs) are a small sub-group of kinases containing three members: VRK1, VRK2, and VRK3. These proteins are involved in the cell cycle, cellular proliferation, chromatin condensation and gene transcription. VRK1 has been extensively studied not only for its normal biological roles, but also for its link to cancer. VRK2 is not as well studied as VRK1. However, the two kinases are …


Synthesis And Characterization Of Cdse Nanoparticles For Use In Solar Cells, Benjamin A. Carvell Apr 2023

Synthesis And Characterization Of Cdse Nanoparticles For Use In Solar Cells, Benjamin A. Carvell

Research & Creative Achievement Day

Over the last several years, interest in thin-film, nanoparticle-based solar cells have increased due to their potential to be low cost, tunable, and highly efficient when compared to other current solar cell technologies. In this research, cadmium selenide nanoparticles capped by oleic acid (CdSe-OLA) were synthesized. After those nanoparticles were synthesized, the bulky oleic acid ligand was exchanged with much smaller, more tunable ligands such as vanillic acid, malic acid, and Sodium 2,3-Dimercaptopropane-1-sulfonate (DMPS). This allows for easier energy transfer when applied to a solar cell. The successful synthesis of these nanoparticles was confirmed using FTIR, UV-vis, and NMR spectroscopy. …


Investigations Of The Effects Of Mutations In Inscuteable Mediated Pins-Mud Complex And Par Complex Functions In Drosophila Neuroblast, Ryan Liu Apr 2023

Investigations Of The Effects Of Mutations In Inscuteable Mediated Pins-Mud Complex And Par Complex Functions In Drosophila Neuroblast, Ryan Liu

Research & Creative Achievement Day

Drosophila melanogaster central brain neuroblasts asymmetrically segregate proteins along the cell's apical-basal axil. Divisions along abnormal orientations or the complete failure to divide asymmetrically may result in overgrowth phenotypes. Neuroblastoma, one of the deadliest solid tumor diseases with extremely poor survival rate for late stages, is an example of this dysregulation. The protein Inscuteable (Insc) was previously found to bind with the protein Partner of Inscuteable (Pins; mPins or LGN in mammals), a receptor-independent G-protein activator, which is a subunit of the Pins-Gαi complex. The combined complex recruits Dlg to ensure correct spindle attachment on the cortex of the cell, …


Validation Of Computational Methods For The Tautomerism Of Thiourea Dioxide, Mckenna Lund Apr 2023

Validation Of Computational Methods For The Tautomerism Of Thiourea Dioxide, Mckenna Lund

Research & Creative Achievement Day

In solution, thiourea dioxide exists in an equilibrium between its dioxide and sulfinic acid forms. This tautomeric relationship, as they all are, is substantially influenced by the solvent's polarity and hydrogen bonding capabilities. More well-known systems, e.g., acetylacetone, have been extensively studied in this regard, while thiourea dioxide's equilibrium has not. We have initiated a hybrid computational-spectroscopic investigation of this system utilizing low-cost Hartree-Fock methods with the 3–21G, 3–21+G, 3–21G*, 3–21+G*, MINI, MIDI, SBKJC and HW basis sets. Beyond gas phase calculations, both tautomeric forms were modeled using the C-PCM implicit solvent model for water and toluene. Obtained modeling results …


Volume 14, Ireland Seagle, Dalton C. Whitby, Cassandra Poole, Rachel Cannon, Heidi Parker-Combes, Devon G. Shifflett, Antonio Harvey Apr 2023

Volume 14, Ireland Seagle, Dalton C. Whitby, Cassandra Poole, Rachel Cannon, Heidi Parker-Combes, Devon G. Shifflett, Antonio Harvey

Incite: The Journal of Undergraduate Scholarship

Table of Contents:

  • Introduction: Dr. Amorette Barber
  • From the Editor: Dr. Larissa "Kat" Tracy
  • From the Designers: Rachel English, Rachel Hanson
  • Hungry Like the Wolf: The Wolf as Metaphor in Paramount Network’s Yellowstone: Ireland Seagle
  • “Floating Cities”: Illustrating the Commercial and Conservation Conflict of Alaskan Cruise Ship Tourism: Dalton C. Whitby
  • What Can You Do When Your Genes are the Enemy? Current Applications of Gene Manipulation and the Associated Ethical Considerations: Cassandra Poole
  • La doble cara: un tema romántico en las obras de Larra y Hawthorne: Rachel Cannon
  • Resolving a Conflict: How to …


Synthetic, Catalytic, And Mechanistic Studies Of Supermesityl Phosphiranes And Phosphines, Ryan M. Tipker Apr 2023

Synthetic, Catalytic, And Mechanistic Studies Of Supermesityl Phosphiranes And Phosphines, Ryan M. Tipker

Dartmouth College Ph.D Dissertations

Methylation of P-stereogenic phosphiranes Mes*PCH2CH(R) (Mes* = 2,4,6-(t-Bu)3C6H2, R = Me, Ph) with MeOTf gave P-stereogenic phosphiranium cations; [Mes*P(Me)CH2CH(Ph)][OTf] underwent syn-anti isomerization via P-epimerization. Mechanistic studies suggested ring opening gave a hyperconjugation-stabilized carbocation in which pyramidal inversion at P was promoted by s-interaction with the pendant cation. Attempted phosphirane protonation with HOTf resulted in ring opening and C-H activation of an o-t-Bu group to give phospholanium cations. Treatment of [Mes*P(Me)CH2CH(Ph)][OTf] with LiPPh2 gave bis(phosphino)ethanes. Copper- catalyzed P-alkylation of the secondary phosphine PHPh(Mes*) with benzyl bromides gave P-stereogenic tertiary phosphines with a supermesityl substituent.


Cooperative Heterometallic Platforms Enabling Selective C–H Bond Activation And Functionalization Of Pyridines, Manar M. Shoshani Apr 2023

Cooperative Heterometallic Platforms Enabling Selective C–H Bond Activation And Functionalization Of Pyridines, Manar M. Shoshani

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

The development of methodologies for regioselective C–H functionalization of N-heterocycles has seen sustained growth over the last two decades. Cooperative reactivity stemming from the addition of Lewis-acidic metals to late-transition-metal complexes has enabled regioselective catalytic transformations. Progress in the design of ligands and Lewis-acidic metal precursors has led to development of in situ cooperative catalysts able to facilitate C–H functionalization of pyridine at C-2, C-3, and C-4 positions. Very recently, focused efforts toward well-defined heterometallic complexes facilitating C-H bond catalysis have been targeted. Transformations showcasing regioselective C-2 transformations have been achieved. This perspective examines select examples delineating the evolution …