A5073123654- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- N-Heterocyclic Carbenes in Organic and Inorganic Chemistry
- Metal complexes synthesis and properties
- Catalytic Cross-Coupling Reactions
- Asymmetric Hydrogenation and Catalysis
- Organometallic Complex Synthesis and Catalysis
- Magnetism in coordination complexes
- Crystallography and molecular interactions
- Various Chemistry Research Topics
- Metal-Catalyzed Oxygenation Mechanisms
- Metal-Organic Frameworks: Synthesis and Applications
- Biochemical and Molecular Research
- Catalytic C–H Functionalization Methods
- Metabolism and Genetic Disorders
- Diet, Metabolism, and Disease
- Chemical Reaction Mechanisms
- Carbon dioxide utilization in catalysis
- Coordination Chemistry and Organometallics
- Aerogels and thermal insulation
- Enzyme Catalysis and Immobilization
- Organic and Molecular Conductors Research
- Higher Education Research Studies
- Nanomaterials for catalytic reactions
- Engineering Education and Pedagogy
Fairfield University
2011-2025
Fairfield Hospital
2020
Centre National de la Recherche Scientifique
2005
Université de Montpellier
2005
Yale University
2002-2004
Universitat Jaume I
2004
Hartford Financial Services (United States)
2000
Trinity College
2000
The new air-stable and moisture-insensitive Ir catalysts for efficient transfer hydrogenation of ketones contain a chelating bis(N-heterocyclic carbene) ligand. Most other hydrogen show activity Rh > Ir, but we find these cases. Tuning the ligand wingtip substituents, R, can greatly increase catalyst (R = neopentyl) or selectivity isopropyl). Reactivity studies isotopic labeling are consistent with monohydride mechanism transfer.
Chelating bis(imidazolium) salts having (CH2)n chains of different lengths (n = 1−4) linking the diazole rings show very large reactivity differences on metalation with [(cod)RhCl]2. Long linkers favor a square-planar Rh(I) product, while short octahedral Rh(III). We ascribe origin effect to restricted rotation highly sterically anisotropic and preferred orientations these as n changes. Defining x y axes Rh−carbene bond directions, we find that tend be oriented close xy plane. This tends...
Some neopentyl-substituted NHC iridium complexes catalyze the reduction of a variety aldehydes and even enolizable by hydrogen transfer from refluxing 2-propanol with alkali-metal carbonate bases. Imidazole 1,2,4-triazole had comparable activities. The could also be reduced more slowly using mild base no complex.
Changing the counteranion along series Br, BF4, PF6, SbF6 in their ion-paired 2-pyridylmethyl imidazolium salts causes kinetic reaction products with IrH5(PPh3)2 to switch from chelating N-heterocyclic carbenes (NHCs) having normal C2 (N path) abnormal C5 binding (AN path). Computational work (DFT) suggests that AN path involves C-H oxidative addition Ir(III) give Ir(V) little anion dependence. The N path, contrast, goes by heterolytic activation proton transfer adjacent hydride. is...
Interconversion of the two chiral conformations square planar Pd(II) CCC pincer carbene complex, 1 (η3-C,C′,C″) (2,6-bis{[N-methyl-N′-methylene]imidazol-2-ylidene}phenyl)bromopalladium(II), and CNC cation, 2, (η3-C,C′,N)(2,6-bis{[N-methyl-N′-methylene]imidazol-2-ylidene}pyridine)bromopalladium(II)(1+), is characterized by VT NMR spectroscopy. Combined DFT/experimental work indicates alternative mechanisms. In case 1, having no counterion, several derivatives 2 with weakly nucleophilic...
Changing the counter-anion in 2-pyridylmethyl imidazolium salts (Br, BF4, PF6, SbF6) causes their kinetic reaction products with IrH5(PPh3)2 to be switched from normal C-2 abnormal C-5 binding.
We have synthesized novel cobalt(II) and nickel(II) pincer ligand complexes containing tridentate precursors that coordinate via oxygen, nitrogen, oxygen donor atoms. The ONO ligands, which are neutral, incorporate a carbonyl-substituted imidazole functionality contain R groups of ethyl, isopropyl, or tert-butyl. were thoroughly characterized using NMR spectroscopy, ESI-MS, IR spectroscopy. metal single crystal X-ray diffraction, elemental analysis, cyclic voltammetry. with t-butyl wingtip...
A series of tridentate pincer ligands, each possessing two sulfur and one nitrogen donor (SNS), based on bis-imidazolyl or bis-triazolyl salts were metallated with CuCl2 to give new SNS copper(I) complexes [(SNS)Cu]+. These orange exhibit a three-coordinate pseudo-trigonal-planar geometry in copper. During the formation these complexes, disproportionation is observed as copper(II) salt precursor converted into Cu(I) [(SNS)Cu]+ cation [CuCl4]2– counteranion. The characterized single crystal...
As part of a university-wide project to explore Shakespeare's classic play, Romeo and Juliet, from variety perspectives, an interdisciplinary talk was presented the university community on chemistry potions poisons referenced in Juliet. To draw multidisciplinary audience teach about forensics as well pharmaceutical herbs chemicals, presentation given perspective how modern crime scene investigator would approach famous play's final death without any prior knowledge situation. An autopsy...
Enzymes in the oxygen-activating class of mononuclear non-heme iron oxygenases (MNOs) contain a highly conserved center facially ligated by two histidine nitrogen atoms and one carboxylate oxygen atom that leave face metal (three binding sites) open for coordination to cofactor, substrate, and/or dioxygen. A comparative family [FeII/III(N2On)(L)4−n)]±x, n = 1–3, L solvent or Cl−, model complexes, based on ligand series supports N,N,O core is then modified either additional chelate arms, has...
In this article, the strategies and techniques used to successfully teach advanced inorganic chemistry, in lecture laboratory, a legally blind student are described. At Fairfield University, these separate courses, which have physical chemistry corequisite or prerequisite, taught for junior senior biochemistry majors. A earns grade each (three credits) laboratory course (two credits). An overview of topics is given, followed by general accommodations specific approaches that were used....
A three-week laboratory experiment, which introduces students in an advanced inorganic chemistry course to air-sensitive and catalysis, is described. During the first week, synthesize RuCl2(PPh3)3. second third weeks, characterize formed coordination compound use it as a precatalyst for oxidation of 1-phenylethanol acetophenone. The synthesized RuCl2(PPh3)3 characterized using 1H 31P NMR spectroscopy, IR magnetic susceptibility measurements. run catalytic control reactions determine percent...
This work reports the first example of mono-nuclear Cu pincers with SNS ligation acting as electrocatalyst precursors for electrochemical conversion carbon dioxide to CO and H<sub>2</sub> in protic organic media.
American Chemical Society (ACS) National Meetings are valuable for the development of undergraduate researchers but can be overwhelming first-time attendees. To orient and engage students with range offerings at an ACS meeting, we developed a cloud-based scavenger hunt. Using their mobile devices, teams undergraduates "scavenged" items off list by uploading "selfies" to designated folders within Google Drive, storage system. Time stamps offered cloud afforded real-time evidence student...
Chemical model complexes are prepared to represent the active site of an enzyme. In this protocol, a family tridentate pincer ligand precursors (each possessing two sulfur and one nitrogen donor atom functionalities (SNS) based on bis-imidazole or bis-triazole compounds) metallated with CoCl2·6H2O afford SNS cobalt(II) complexes. Preparation for liver alcohol dehydrogenase is facile. Based quick color change upon adding acetonitrile solution that contains precursor, complex forms rapidly....