Joshua Davis

Mapping the Reactivity Surface of Metal-Olefin Reactions

Among the basic organic molecules, there is the olefin.  The olefin possesses two carbon atoms double bonded to each other.  When a metal is bonded to the double bond in the olefin, the resulting metal olefin compound can be used as an intermediate to make many other compounds.   In understanding how these metal-olefins react, better industrial processes can be developed.  The metal to olefin bond is not always symmetrical.  Depending on what is bonded to either carbon atom, the metal can be displaced closer to one carbon or another.  The purpose of this study is to understand how the asymmetry of the metal olefin can affect the rate of nucleophilic attack.  Previous studies suggest that as the asymmetry of the metal olefin increases, the rate of nucleophilic attack also increases, but only to an extent.  If the asymmetry is too large the reaction stops completely.

In order to optimize the symmetry of the metal-olefin, the rate of nucleophilic attack must be measured by using several derivatives of metal-olefins.  The symmetry of these derivatives will vary and be well characterized.  Our goal is to develop reproducible ways of measuring the rate of these reactions.  Before the rate of reaction can be measured, the initial concentrations of the nucleophile and metal-olefin must be measured accurately.   The two issues that are delaying our progress are learning correct technique and solvent and reactant compatibility.  Solutions of the metal-olefin complex are air-sensitive so they must be prepared under air-free conditions, with special glassware and techniques.  If air is introduced into the solution during the prep of the solution or in the concentration measurement, it can lead to an inaccurate measurement of concentration.  Some of the solvents we have used in our study have been shown to react with our reactants which also lead to inaccurate measurements of concentration.  We are currently on our forth solvent system.  With further exploration we will improve our methods enough to eventually measure reproducible kinetics data.

Faculty Mentor: Stephen Matchett, Chemistry

Page last modified July 20, 2010