Graham Bodwell’s group is working the synthesis of severely distorted polycyclic aromatic hydrocarbons (PAH) and studying the effects of such distortion on the chemical and physical properties of the aromatic system. The largest aromatic system under investigation is teropyrene, which is a C36 decacyclic PAH.
Recent work has led to the development of a gram-scale synthesis of a (2,11)teropyrenophane, in which the teropyrene system is bent into almost a semicircle. Having access to synthetically useful amounts of material has enabled the exploration of the chemistry of the teropyrene system for the first time (Angew. Chem. Int. Ed. 2018, 57, 1707–1711). It was discovered that electrophilic aromatic substitution with molecular bromine readily affords a single tetrabromide. The very high regioselectivity of this reaction could be explained using the results of an EPR study of the easily-formed radical cation of the unbrominated cyclophane.
The research group of Travis Fridgen is exploring the interactions of metal ions with biomolecules and the fundamental forces which give biomolecules their three-dimensional shape. Graduate and undergraduate research student's in Dr. Fridgen's group are using state-of-the-art instrumentation, combining ion-trapping mass spectrometry with tunable infrared lasers to spectroscopically probe the structures of these ions in the gas phase. Recently (DOI: 10.1021/jp809993k) they have shown that solvating metal-ion bound DNA bases results in a huge structural change, promoting intramolecular hydrogen bonding.
Erika Merschrod's group is developing new types of protein scaffolds for use in cell culture and tissue engineering. This exciting work involves contributions from undergraduate and graduate students working with a range of cutting-edge biomaterials research techniques.
A major issue in creating a successful tissue scaffold is being able to optimize the structure across length scales. A recent paper from the Merschrod group in the journal Langmuir (DOI: 10.1021/la703292h) presents a new approach to templating materials with control from the nanoscale to the macroscale.
Several students in the Fran Kerton group have been developing polymerization catalysts based on earth abundant metals. In 2015, Hart Plommer (PhD candidate) saw his work on Aluminum catalysts published in Dalton Transactions. His catalyst showed an interesting structure-activity relationships for the ring-opening polymerization of epoxides to yield polyethers. With his most active catalyst, he was able to use an extremely low catalyst loading. He also designed the cover page for this special issue on earth-abundant elements in catalysis. The image in the background is a photo he took in Gros Morne National Park. Also in 2015, Dalal Alhashmialameer (PhD candidate) saw her work on ring-opening polymerization of lactide published in Dalton Transactions. Her report includes details on one of the most active sodium catalysts for this reaction to date. The product of her reactions poly(lactic acid) or PLA is a biodegradable polymer. Both of these papers are available free via an open-access license. Other researchers in Dr. Kerton's group work on carbon dioxide activation, biomass utilization and oxidation catalysis. Find our more about Green Chemistry @MUN by visiting our group's website.
Recent work by Peter Warburton and Ray Poirier has looked at defining both atoms and bonds in molecules by looking at the radial electron density. Continuing work in this direction will lead to new techniques in molecular modeling that are anticipated to significantly speed up many molecular modeling calculation types.
Since the arrival of Drs. Kerton and Kozak at Memorial University in September 2005, Green Chemistry has taken off and grown from being the focus of two researchers to over eleven in just three years. So what is Green Chemistry? Another name for it is Sustainable Chemistry and it is all about preventing environmental pollution from occurring by developing new, innovative chemicals and chemistry. A special article on Green Chemistry at MUN was published in the Gazette. (http://today.mun.ca/news.php?news_id=4242)
The Rowley group uses computer simulations to study biochemical systems, including the permeation of drugs and toxins across cell membrane and the covalent inhibition of proteins. A diverse range of computational methods are used, including ab initio molecular dynamics, high level ab initio methods, polarizable force fields, and QM/MM models. New computational methods are also developed to achieve greater accuracy and to explore larger, more complex systems. These simulations are performed on the national Compute Canada supercomputing facilities. Their work examining how the toxic gas hydrogen sulfide is able to cross cell membranes was published in the prestigious Journal of the American Chemical Society (DOI: 10.1021/ja508063s). The Rowley group's research has been recognized by the President's Award for Outstanding Academic Research and the ACS OpenEye Outstanding Junior Faculty Award in Computational Chemistry.
The Katz group studies porous materials; an example of a porous material that we use every day is a sponge in our kitchen. The focus on the research program is to study the synthesis, properties, and applications of these materials. The main class of porous materials that the research team investigates are metal-organic frameworks (MOFs). MOFs are made from inorganic metal cations or clusters which are connected to one another via organic bridging ligands (e.g., terephthalic acid). The structures of MOFs are such that a large percentage of framework-free space (e.g., like the pockets in a sponge) is available for chemistry (e.g., like absorbing water in a sponge). Unlike the sponge example, one of the research themes within the group focuses on studying how environmentally harmful chemicals are absorbed into a porous material. With this in mind, the research team is a multidisciplinary team that combines organic, inorganic, and physical chemistry methods to address many challenges. In a related manuscript published in Chemical Communications (DOI: 10.1039/C5CC09919F), the research team studied how a particular class of MOFs changes as a function of time. By understanding how and why these materials change over time, we can understand how they will function in various applications. Recently, Dr. Katz has received the Terra Nova Young Innovator Award. This funding opportunity will allow the research team to begin to investigate a new class of porous materials.