Preparation, characterization and study of the reactivity of high energy intermediates formed in metal-atom reactions

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Activated metals have had a significant impact on organic synthesis.  Also, many industrially important processes use metals as catalysts.  The efficiency of the processes depends on the nature of the metal, the material on which it is supported and the techniques available to introduce the metal into the support.  My research program involves studying the reactions of metal atoms with the aim of understanding the mechanisms controlling metal mediated catalysis, surface chemistry and the formation of organometallic compounds.  Metal atoms will be reacted with organic compounds at -196 degrees Celsius in a high vacuum chamber called a 'rotating cryostat'.  Pieces of metal wire or pellets heated in a furnace will be used to generate the metal atoms.  The products generated in the metal atom reactions are special in that their instability affords them extraordinary reactivity.  We will take advantage of the unusual reactivity of these compounds by treating them with appropriate reactants between -196 degrees Celsius and room temperature to provide new synthetic routes with increased reaction rates, product yield and cost efficiency.  Cyclic compounds containing a metal atom, i.e., metallacycles, are important intermediates implicated in many catalytic processes.  We will study how these intermediates are formed as well as their ability to react with compounds containing electron-deficient centres.  In addition, to gaining a better understanding of catalytic processes, we will investigate the nature of the organometallic intermediates formed in a number of different metal atom reactions.  To do this the intermediates will be collected and their structure determined by a spectroscopic technique known as electron paramagnetic resonance (EPR) spectroscopy.  The parameters extracted from the spectra will give us information about the bonding characteristics of metal-centered radicals generated in our reactions.  Some of the systems we will investigate include organomagnanese intermediates, intermediates formed in yttrium atom reactions and organometallic complexes of zerovalent copper.