The Department of Chemistry at the University of Victoria.
There are 19 faculty members in the Department of Chemistry at the University of Victoria, with experience in almost every major field of chemical science. The department's moderate size lends itself to a close working relationship between faculty and students. In addition, an undergraduate enrolment of over 1,200 chemistry students means chemistry is a major department on the campus and one that receives a full measure of support, both in teaching and research facilities.
Departmental teaching, research and instrument laboratories occupy some 3,500 square meters in the Elliott Building, which also accommodates the Department of Physics, and an additional 360 m square in the new Science and Engineering complex adjoining the Elliott Building, completed in 1986. The close arrangement and grouping of all the science departments on the campus promotes easy interaction and a broad awareness of the full range of scientific activity at the university.
The department is exceptionally well equipped. Major items of instrumentation serving both teaching and research needs include: two automated X-ray diffractometers, including a Nonius CAD-4/VAX11/730 system; five NMR instruments, including two superconducting multinuclear Fourier Transform spectrometers (250 MHz and a 360 MHz to arrive this year), variable temperature and decoupling facilities; an Hitachi-Perkin Elmer RMU-7 double focusing mass spectrometer; a Finnegan gas chromatograph-mass spectrometer equipped with a chemical ionization source, data acquisition system, and negative ion capability; a Bruker E200TT ESR spectrometer with ENDOR facilities and computer, as well as a Varian E6S ESR; a Princeton Applied Research 370 electrochemical system; a Laser Raman spectrometer; a Perkin Elmer 141 polarimeter; a range of UV and IR spectrometers; liquid (analytical and preparative) and gas chromatographs; and high pressure hydrogenation apparatus.
Among the specialized equipment associated with particular research groups are: a single photon luminescence decay spectrometer; an automated quantitative ion exchange chromatograph; a spectrofluorimeter with provision for automatic data collection; three stopped-flow spectrometers; several 1.5 m W gas lasers; interferometers; two video cameras and video records; a time domain reflectometer; a data acquisition system for preparation of video-taped data to the university computer; a Baird-Atomic 1.5 m stigmatic grating spectrograph; a Jarrell-Ash 3.4 m Ebert grating spectrograph; a PDP11 centered CAMAC data acquisition computer; a photoelectron spectrometer; and a liquid helium cryostat for the Bruker ESR photochemical reactors.
Adjacent to the Elliott Building is the McPherson Library, with a primary collection of 1.1-million volumes, over a million items on microform and more than 20,000 records and tapes. The library can provide on-line bibliographic search services to data bases such as CAN/OLE. Chemistry and related titles currently total over 11,000, in addition to 325 chemistry journals. Students, faculty and staff all have equal borrowing privileges. The department also maintains its own reading room and reference section.
The university's Computer Centre is housed in the Clearihue Building, next to the McPherson Library. The university's IBM and VAX mainframe systems operate 24-hours a day for faculty and student use. Terminals and remote entry installations are located throughout the Chemistry Department for data acquisition and transfer of on-site computing. Department computer holdings include a VAX 11/730, two PDP 11/23, a PDP11/10 and PDP 11/micro, other specialized computers for instrument automation, and many departmental and research-owned micro-computers.
During recent years, close working ties with industry and with government research centres have developed through the Co-operative Education Programme, already well established for undergraduate students and now being extended to include graduate students. Liaison with applied research is also growing through contact with Discovery Park, the name given to a scheme to encourage commercial ventures involving high technology to locate their premises on or near to the university campus. In collaboration with federal government agencies and private organizations, the chemistry department has been active in areas of applied research such as environmental toxicology, coal liquefaction/gasification, and biotechnology.
The department offers programmes leading to the degrees of master of science and doctor of philosophy. Research areas include: organo-metallic chemistry; inorganic kinetics; transition metal chemistry; inorganic photochemistry; hydrides of silicon; transition metal chemistry; multinuclear NMR studies; synthetic organic chemistry; natural products; biogenesis; physical organic chemistry; photochemistry; kinetics and mechanisms; free-radical chemistry; structural studies; x-ray crystallography; molecular spectroscopy; electrochemistry and electrode kinetics; surface phenomena; solid state luminescence; electron impact phenomena; molecular orbital calculations; photoelectron spectroscopy, membrane transport processes and bioinorganic chemistry.
Now for a brief description of each faculty member and their research work.
Walter J. Balfour, FCIC Infrared, Raman and especially electronic absorption and emission spectroscopy are being used by Balfour and his co-workers to study the structure and bonding in diatomic and small polyatomic molecules. Laboratory spectra of diatomic molecules of chemical and astrophysical interest currently under investigation include FeH, MnH and ReO.
Studies on polyatomic molecules are concerned principally with inductive and mesomeric effects in the (pi(*),pi) electronically excited states of substituted benzenes and the effects of conjugation on the energies, geometries and stabilities of singlet and triplet (pi(*)n) excited states of organic carbonyl compounds.
Graham R. Branton, MCIC Branton's interest centre around the analytical applications of physical methods. Primary interests involve the investigation of species which show large cross-sections for the production of negative ions, with secondary interests in chromatographic methods. To be useful analytically, a species with a large negative ion production cross-section must be sufficiently volatile to be examined via negative ion mass spectrometry and/or electron capture gas chromatography.
A programme of synthesis and examination of complexes and ligands which might be suitable is underway. The electronic effects within the ligands are being investigated by photoelectron spectrometry and the complexes themselves by mass spectrometry and gas chromatography. The negative ion sensitivity for mass spectrometive detection offers the potential for trace studies using stable isotopes.
Gordon W. Bushnell, MCIC His group is mainly involved with coordination compounds from close to the end of the transition series of elements. They have recently determined a number of novel five-coordinate structures of Cu(II) and Zn(II), and have examined compounds containing elements in rare and interesting oxidation states such as Ag(+2), Pd(+4/3), and Ir(+2). Correlations are made between NMR observations on solutions and crystal structure results, interrelationships which have involved ring current shielding, fluxional processes, and spin-spin coupling constants.
Work has been done on the transinfluence in Pt(II) chemistry, and there is an interest in the molecular mechanism of carcinostatic drugs which are coordination compounds, with particular emphasis on the field of Pt(II) chemistry centred around cis-(Pt2Cl2(NH3)2) and the Cu(II) thiosemicarbazone area. X-ray crystallography can show how these compounds react with the component parts of DNA. Recent work on the stereochemistry of the lone pair in Pb(II) complexes is pure chemistry linked with the practical concerns of lead poisoning and its treatment with chelating agents. Crystallographic results give the complete crystal structure, intermolecular interactions, space group symmetry, and bonding networks.
Thomas W. Dingle, MCIC Dingle's interests in theoretical chemistry are directed towards calculating various properties of atoms and molecules. This involves developing new methods and using standard techniques on systems of interest to colleagues in the Chemistry Department. Attempts are being made to calculate NMR spin-spin coupling constants by modifying the Fermi-contact operator to account for finite nuclear size, removing the difficulties associated with the Dirac delta function. Another investigation involves the calculation of the energies and electron distributions of some benzannulenes to explain their properties and predict possible new and novel compounds in this area. A third project involves the calculation of the different ionization energies of molecules determined by photoelectron spectroscopy.
UVic participates in the nuclear accelerator programme at UBC (TRIUMF) which studies muons, particles like an electron but much more massive. Calculations have begun on the energy levels of the particle when it is captured by normal molecules.
Keith R. Dixon, FCIC The platinum group metals are of great current interest for their fundamental chemistry, for their technological importance in a wide variety of catalytic processes and, most recently, for their use in anti-cancer drugs. During the 1980s, the work of Dixon's group has concentrated on studies of these metals and includes the synthesis of many previously unknown complexes, computer analysis of unsual 31P and 195 Pt NMR spectra, dynamic NMR studies of fluxional systems including examples where access to a specific coordination site is controlled by a strongly bonded metal-ligand pivot, and synthetic and reactivity studies of novel tri-palladium and platinum/dipalladium cluster systems. Some x-ray structural work related to the action of platinum complexes as anti-cancer drugs has also been carried out.
On-going research is directed towards the discovery of new complexes and reactivity patterns for platinum metals, especially those of technological importance in catalytic processes, or relevant to chemotherapeutic use.
Alfred Fischer, FCIC The investigation of organic reaction mechanisms is the principal area of research of Fischer and his group. An active field of study is the formation of adducts accompanying electrophilic substitution of aromatic compounds, involving attack on the electrophile at an ipso (substituted) position. Such adducts, obtained as a pair of diastereoisomers, rearomatize by a variety of pathways which are being elucidated. Cyclohexadienyl cations are intermediates in both adduct formation and rearomatization reactions and the study of these reactions provides significant information concerning the chemistry of cyclohexadienyl cations. Some substrates give rise to conjugated diene adducts from 1,2 addition and these adducts exhibit radical and sigmatropic rearrangement pathways.
Thomas M. Fyles, MCIC One of the more intriguing developments of the past decade has been the emergence of the field of `biomimetic' chemistry. This field's rationale is to prepare artificial mimics of natural processes like receptors, catalysts or membrane transport systems. In addition to providing insight into the natural systems these studies often lead to applications in analytical chemistry and separation science. Fyles' research interests lie within this domain with particular emphasis on the synthesis and characterization of artificial receptors and transport systems for cations and anions. Syntheses centre on macrocyclic ligands of the crown ether or cryptand type and related complexing agents. Characterization of the ligands prepared relies on NMR and other spectroscopic techniques and potentiometric methods.
The transport of cations and anions across various types of artificial membranes has been a central theme of this research programme and various analytical methods are in place to study this process. Thus, although the projects are grounded in synthetic organic chemistry, other aspects of physical, inorganic, biological and analytical chemistry are involved.
David A. Harrington, MCIC His research is in electrochemistry and surface science. Recently available are the means of preparing well-ordered, contaminant-free single-crystal electrodes. Studies on electrode processes on these surfaces have led to better adsorption at the solid-liquid interface. The techniques of low energy electron diffraction, auger electron spectroscopy, thermal desorption spectroscopy and work function measurement are used.
Typically, clean single-crystal electrodes are prepared in ultra-high vacuum, and are then transferred to an electrolyte solution at atmospheric pressure to undertake an electrochemistry study. The products of the process are characterized after pumping down to UHV and applying the above techniques. Molecular-level information about the composition and structure of the species at the interface can be obtained. Understanding electrode processes on single-crystal surfaces aids in the understanding of the more complex processes in electrocatalysis, corrosion, batteries and fuel cells.
Martin B. Hocking, MCIC Synthetic hererocyclic chemistry, related mainly to the preparation and chemistry of phospholes, is of continuing interest to Hocking. This class of heterocycle is being examined with respect to its aromaticity and stability, particularly with reference to a variety of dienophiles.
He is also interested in the mechanistic and synthetic aspects of the chemistry of aqueous peroxides, and hydrogen peroxide in particular. For example, Dakin oxidation of o-, and p-hydroxyacylphenols has been examined in some detail. The results obtained are relevant to commercial options for the production of catechol or hydroquinone. Aspects of this work also relate to the mechanism of anthraquinone-promoted pulping, and to the peroxide bleaching of wood pulps for use in papermaking.
Alexander D. Kirk, FCIC Photoreactions of transition metal complexes, mainly of chromium(III), and related absorption and luminescence spectroscopy are being investigated by Kirk and his colleagues. Past research has emphasized studies of the reaction modes and stereochemistry of chromium(III) complexes and testing of various theoretical models. This has involved preparative, analytical and photochemial research.
Luminescence and transient absorption has been studied to yield information on energies and lifetimes of participating electronically excited states, rates of photophysical processes, and the role of energy transfer and quenching processes. This has involved low-temperature solid state studies with laser flash and photon counting techniques. Picosecond laser flash kinetic spectroscopy has revealed rapid intersystem crossing in some chromium(III) complexes and fast transient absorption processes in a variety of different types of metal complexes.
Future plans include continuation of these studies, extension to studies in nonaqueous solvents and at high pressure, and initiation of selected photoredox studies, some of interest as potential solar energy storage or conversion systems.
Alexander McAuley, FCIC The stability of unusual oxidation states of metal ions and the mechanisms of electron transfer reactions are active areas of research for McAuley and his co-workers. Frequently redox processes take place with the transient formation of radicals. Investigations of reaction pathways are essential for a understanding of many biologically and industrially-related systems. Nickel(III) centres may be stabilized by coordination of a macrocyclic (N-donor) ring and are formed readily from the corresponding Ni(II) species by oxidation in acidic aqueous (Co(3+)aq) or non-aqueous (NO+) solvents. With tetraazamacrocycles, axial coordination of ligands is confirmed by ESR measurements. Using the triazamacrocycle (9-aneN3), a very stable Ni(III) (9-aneN3)(3+)6 ion has been isolated. Since the NiN6 octahedral chromophore is maintained intact during redox, electron self exchange rates may be evaluated. The first stable palladium (III) ion Pd (9-aneN3)(3+)(2) has also been prepared and is the subject of investigation.
Attempts are also underway at encapsulation of metal ions (Co, Ni, Fe, Cr) in macrobicyclic ligand systems. Such species, stable under a variety of conditions, constitute ideal examples of outer-sphere electron transfer reagents. Reactions with both inorganic and organic reductants have been completed. Synthesis of bi- and tri-metallo macrocycles is continuing with a view to multi-electron transfer systems.
Reginald H. Mitchell, FCIC Mitchell's interests centre around synthetic organic chemistry, novel aromatic compounds, and molecules of theoretical interest. His group constantly searches for new methods of synthesizing unsaturated macrocyclic compounds, and of modifying their functionality. This involves a variety of organosulphur and selenium reactions, as well as more recently organometallic compounds. Particularly interesting are the aromatic molecules that show bond localization properties, for example, benzannelated aromatics, small-ring fused aromatics, and metal-complexed aromatics. Routes have been devised to synthesize such species, which are then examined spectroscopically to test if theoretical predictions derived from molecular orbital calculations are valid. Careful study of the physical and chemical properties of such molecules determines how well the behaviour of the molecule fits the theory, and hence whether theory needs to be modified.
Under recent study has been the interacting-clouds in metacyclophanes, bond localization in benzannulenes, bond fixation in cyclobutadihydropyrenes, cyclophanes with jumbo-sized internal substituents, biradicaloid annulenes, and chromium carbonyl derivatives of both cyclophanes and benzannulenes. The latter area is the beginning of an approach to an organic conductor.
Gerald A. Poulton, FCIC The major focus of Poulton's research programme is directed towards the study of the chemistry and biological activity of naturally occuring secondary metabolites of fungal pathogens and other native species. These investigations involve the isolation of major components, and the elucidation of their structure. Synthetic approaches are incorporated, not only in the preparation of model compounds for study and in the total synthesis of the natural products themselves, but also in the preparation of compounds to be used in biosynthetic investigations.
Recent studies have involved nitrogen and oxygen heterocycles, particularly compounds of the pyridine and pyrone families, and the techniques of chromatography (including HPLC), mass spectrometry, GCMS, chemical ionization mass spectrometry and NMR (both 1H and 13C) are used extensively.
Frank P. Robinson, FCIC Mechanistic studies being undertaken by Robinson include synthesis and thermolysis of optically active and isotopically labeled azo compounds, using kinetic methods and CIDNP. Studies have involved structure-reactivity correlations on pyridine and naphthlene derivations, by pKa measurements and 1H and 19F nuclear magnetic resonance spectroscopy.
Other interests include rearrangements of phthalides to indanediones, and hydrolysis of metal ion complexes of biacetylacetone-ethylenediamine analogues.
Stephen R. Stobart, MCIC Catalytic activation of inert substrates like CO2 or CH4 by transition-metal complexes is a major current research objective with important implications for energy utilization. Unique properties imparted by coordination environment are critical in promoting metal-catalyzed reactions; in Stobart's laboratory, synthetic chemistry is revealing how electronic and steric factors can influence reactivity at a transition-metal site. Coordinatively unsaturated metal centers, which are electron-rich, mimic reactive metal surfaces and accordingly nucleophilic behaviour of such species frequently provides a pathway for molecular activation. To explore the effect on metal basicity of inductive release from Si, new ligand systems have been invented in which Si-M bonds are stabilized by incorporation of the silyl function into a chelate framework.
This strategy has led to isolation of novel complexes with unusual stereochemistry and high reactivity where M = Ru, Os, Rh, Ir, Pt: catalytic hydroformylation and CO2 reduction are among areas under continuing development. Electronic communication between adjacent metal sites, which offers a conceptual link between homogeneous and heterogeneous catalysis, is being investigated using pyrazolyl-bridged iridium dimers as molecular models.
A fascinating pattern of redox chemistry is emerging: nucleophilicity of one metal atom is dramatically enhanced through anchiomeric assistance from its neighbor via Ir-Ir bond formation or cleavage; corresponding one-electron reactions afford spin-delocalized bimetallic radicals. Such studies relate directly to mechanistic fundamentals of multicenter oxidative addition and electron-transfer in polymetallic chains.
Peter Wan, MCIC He studies excited state molecules, which in most instances have no ground-state (ie. thermal) analogs, and thus may in most cases be regarded as totally different molecules to their ground-state precursors. His research is directed towards the understanding of the mechanisms and generality of a number of new photochemical reactions discovered recently. Many of these reactions exhibit novel catalytic effects due to water and hydronium and hydroxide ions. Exploratory studies are also being conducted on the use of catalytic surfaces (eg. silica gel; zeolites) as a medium for carrying out photochemical transformations. The channels of zeolites (molecular sieves) have been shown to exert topological control on the course of some photochemical processes.
Paul R. West, FCIC Interest in the structure and reactivity of free radicals derived from biologically important organic molecules is the central theme of research programme. Several rather unusual factors profoundly influence the behaviour of free radical intermediates in the natural environment and in living systems. First the polar solvent properties of water tend to promote transient radical ion formation via ionization or net electron transfers involving the oxidation or reduction of organic species and metal ions. Next, a significant role is played by oxygen fixation involving superoxide, peroxide and oxidizing hydroxyl radicals (.OH).
Processes involving such species include both enzymatic reactions and natural photolytic or radiolytic damage. Current studies highlight these considerations. In aqueous solution near in vivo pH, ESR spectra of radical cations and phenoxyl free radicals are obtained by chemical and peroxidase enzyme oxidation of aromatic amines and phenols. Studies on the reactivity of these transient species toward electron donars (ascorbate, glutathione) and acceptors (oxygen) sheds light on free radical pathways in drug metabolism and carcinogen activation. Related environmental toxicology work involves radical ions and phenoxyl species. Generation of semi-quinone anions from synthetic anti-estrogens (DES analogues) provides intriguing spectroscopic problems (restricted rotations); while revealing potential environmental degradation routes of such species.
PHOTO : Fyles, is shown here with students.
PHOTO : The university campus from the air.
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|Publication:||Canadian Chemical News|
|Date:||Jun 1, 1989|
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