This research program entitled "Asymmetric Hydrogenation at Electrode Surfaces" represents a significant expansion of the prior work by Professor Bernadette Donovan-Merkert of the University of North Carolina at Charlotte and is supported by the Analytical and Surface Chemistry program. The goal of this project is to prepare electrodes capable of chiral electrochemical hydrogenation. Metal complexes with pyrrole-modified chiral ligands will be attached to electrodes via electropolymerization of the pyrrole tether. This strategy allows several metal catalysts to be investigated, both as the pure film or copolymerized so as to increase the conductivity of the film. The chiral electrochemical hydrogenation will be evaluated with acetamidoacrylates, a class of substrates known to give high enantiomeric excess when hydrogenated under homogenous conditions.
Catalytic hydrogenation is a standard chemical reaction and usually yields an equal mixture of two stereoisomers. However, for biological applications, the two stereoisomers can have quite different properties. For example, one isomer may be a sedative while the other other may cause genetic abnormalities. To obtain the desired stereoisomer, there are two routes: One can make both isomers, and then separate the good from the bad. Or, more elegantly and less wasteful, create a chiral catalyst which only makes the desired stereoisomer. This research is focussed on a new style of chiral catalysts which could operate at lower temperatures and pressures, and thus more safely, than previous chiral catalysts.