Main group compounds for bond activation and catalysis

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Most value-added chemicals are produced from feedstock materials by means of catalysis. Catalysts are compounds that change the rate of chemical reactions and allow for chemical reactions to be carried out in a less expensive and more environmentally benign way. Catalysis is involved in a variety of industrial processes in the petroleum refining, energy production, agrochemical, polymer, and pharmaceutical industries, even food industry sectors. It accounts, directly or indirectly, for 20-25% of GDP of industrialised countries. However, most of these important processes are catalysed by late transition metals, such as rhodium and platinum, which are expensive and are recognized to be toxic, which contributes to the cost of synthesis and purification.****Over the past decade, scientists have begun applying main-group chemistry to catalysis to use cheaper and less toxic metals such as aluminum and zinc. Seminal advances include the discovery of heterolytic (ionic) cleavage of strong non-activated bonds by Frustrated Lewis Pairs and its application to hydrogenation of a vast array of substrates and the discovery of oxidative addition reaction of strong bonds to reduced main-group compounds. Although it has not yet been implemented in a practical way, the latter process is potentially a key to an important class of reactions that can couple two compounds together. The fundamental information about this process is rather scarce.****Our research programme is aimed at filling this gap. We shall prepare new families of low-valent main group compounds and investigate activation of strong sigma bonds and multiple bonds on these reduced centres. We expect that unusual and mostly new terminal oxo, imido, and sulfido derivatives of aluminum, zinc, silicon, and germanium will be produced as a result of these reactions. We shall also study the incidence of oxidative addition and its reverse (reductive elimination) reactions from main group centres supported by redox-active (non-innocent) ligands. And, finally, in a biologically inspired project, we shall study the applicability of zinc catalysts to practical reduction of synthetically useful carbonyl compounds by inexpensive and environmentally benign reagents, such as alcohols.****The main benefit to chemistry will be the advancement of scientific knowledge. The main benefit to Canada will be the training of Highly Qualified Personnel and development of more efficient and cleaner catalytic systems.*********