This award by the Inorganic, Bioinorganic, and Organometallic Chemistry Program supports the work of Professor Jack R. Norton at Columbia University to address several areas of homogeneous, organometallic catalysis, specifically: a) electrophilic attacks on metallaaziridines and metallaoxiranes, b) the quantitative measurement of ligand binding to constrained geometry zirconaziridines, c) the enantiofacial selectivity of ionic hydrogenation reactions, and d) zirconium/aluminum transmetallation. Each of these studies advances the fundamental understanding of highly relevant and industrially-important transformations. Professor Norton will continue to educate and train graduate students in detailed mechanistic studies. Undergraduate students in the NSF-sponsored REU program at Columbia University will also participate in the research. Professor Norton will serve as co-Program Chair for the 2008 Mid-Atlantic Regional American Chemical Society meeting.
How chemical reactions occur — their "mechanisms" — are the central interest of the Norton research group at Columbia University. The Norton group has studied the carboalumination of olefins, and the uptake of ethylene by aluminum alkyls. The latter reaction is of interest to companies such as ExxonMobil (they make plastics by such methods) and is important in the manufacture of detergents. The Norton group has shown that both reactions occur by analogous mechanisms, correcting a previous study on the topic. As molecules in biological settings are found only as a single enantiomer, the Norton group tries to make enantioenriched esters of amino acids (the building blocks for proteins). Their method requires a change in the configuration of the carbon next to a transition metal; they have used zirconium, but hope that titanium may give better results with faster enantiomer interconversion. The reaction of carboxylic acids and isonitriles has recently been used in chemical ligation, which is to create long peptide chains and eventually proteins. The method has required harsh conditions, but the Norton group is trying to find a catalyst that will make it happen under milder conditions. Already they have found that a change of solvent can accelerate the reaction.
