Michael GeorgesPh.D. | Professor Emeritus | Chemistry
3359 Mississauga Road
Mississauga , ON
Organic molecules play a role in enabling us to cry, laugh, fall in love and fall out of love. They cause diseases and yet provide many cures. They are ubiquitous in our lives, in many cases without us realizing it. They are fascinating molecules to say the least.
As a fundamental expression of an innate sense of curiosity we continue to explore new ways of manipulating organic molecules, developing in the process unique reaction schemes and organic compounds that hopefully will have the potential to improve our quality of life, be it a cure for an existing disease or simply to allow our clothes to be wrinkle free.
Over the years we have successfully used nitroxide and verdazyl stable radicals as moderators for living-radical polymerizations, presently one of the most popular area of polymer exploration (ref.1, 2). Deviating from this direction we have recently begun to investigate the use of these stable radicals as substrates for small molecule organic synthesis, thus beginning a new journey with a destination still to be determined, but based on initial results, guaranteed to be interesting and challenging. Beginning that journey, we have found that two molecules of verdazyl radical 1 react to form a structurally unique azomethine imine 2, which undergoes [3+2] cycloadditions with various dipolarophiles to give a plethora of diversely functionalized dihydrotetrazinone compounds 3 (ref.3). One of these derivatives has shown an ability to kill acute myloid leukemia cells suggesting a potential application for these molecules.
Equally interesting, many initially formed cycloaddition products, such as 4, undergo unique rearrangements providing challenges in structure and mechanism elucidations.
Our research in the next few years will focus on the study of these heterocyclic compounds both with respect to new reaction design and therapeutic drug applications.
(1) Eric Chen, Delphine Chan-Seng Peter O. Otieno, Robin G. Hicks and Michael K. Georges, Verdazyl Mediated Living-Radical Polymerization of Styrene and n-Butyl Acrylate, Macromolecules, 2007, 40(24), 8609-8616
(2) Dollin, M.; Szkurhan, A. R.; Georges, M. K. Rapid additive-free TEMPO-mediated stable free radical polymerizations of styrene, Journal of Polymer Science, Part A: Polymer Chemistry, 2007, 45(23), 5487-5493
(3) Yang, P.; Kasahara, T.; Chen, E. K. Y.; Hamer, G.; Georges, M. K.; 1,5-Dimethyl-3-Phenyl-6-Oxoverdazyl Radical as a Precursor to an Azomethine Imine for Cycloaddition Reactions, Eur. J. Org. Chem. 2008, 27, 4571-4574