08/23/19 - 4:00 PM to 5:00 PM
Special Seminar: Professor Kallol Ray
Small Molecule Activations at Transitional Metal Centers: Structure-Function Correlations
Small molecule activation constitutes one of the main frontiers of inorganic and organometallic chemistry, with much effort directed towards the development of new processes for the selective and sustainable transformation of abundant small molecules such as dioxygen (O2), water (H2O), hydrogen peroxide (H2O2) or protons (H+) into high-value chemical feedstocks and energy resources. Because nature mostly uses metal ions to activate these relatively inert molecules and modulate their reactivity, much inspiration for the field has come from bioinorganic chemistry. This talk will focus on some of the recent highlights from our group on homogenously catalyzed bioinspired activation of small molecules, as well as stoichiometric reactions that further our understanding towards such ends. It will cover many aspects of small molecule activation including: organometallic chemistry, spectroscopy, synthesis, and detailed mechanistic studies involving trapping of reactive intermediates. The demonstrated examples will help to emphasize the continuous effort of our group in uncovering the structure-reactivity relationships of biomimetic model complexes, which may allow vital insights into the prerequisites necessary for the design of efficient catalysts for the selective functionalization of unactivated C–H bonds, O2/H2O/H2O2 activations, or H+ reductions by using cheap and readily available first-row transition metals under ambient conditions.
Professor Ray’s research focuses on acquiring knowledge from nature about the principles governing reactivities in biological systems that employ common transition metals like copper, iron, manganese, etc. In order to interpret on a molecular level the data of metalloproteins and metalloenzymes, acquired by various physical methods, low-molecular weight synthetic model compounds are necessary as reference substances. His group focuses on synthesizing model complexes (both functional and structural) for monooxygenase and oxidase enzymes using newly designed chelating ligands. A battery of spectroscopic techniques, which cover more than 10 orders of magnitude in photon energy, characterizes the complexes. Different energy regions provide different complimentary insights into the properties of the complexes under study. By choosing the right combination of methods coupled with the ligand field and molecular orbital theories, a definite picture about the electronic structure of the model complexes can be obtained, furthers understanding on the actual enzymatic systems.
Professor Ray earned his bachelor's degree from the University of Calcutta in India, and his master's degree from the Indian Institute of Technology in India. He earned his doctorate at the Max Planck Institute for Bioinorganic Chemistry. He was also a post-doctoral researcher at the Max Planck Institute and University of Minnesota.