STUDIES OF STERIC AND ELECTRONIC BEHAVIORS OF PALLADIUM COMPOUNDS BONDED TO DIPHOSPHORUS
Stephanie Pacheco, Quinetta Shelby.
DePaul University, Chicago, IL.
The overall goal of our research is to produce a palladium catalyst that has been proven to effectively control the stereochemistry of its product. Its effectiveness will be expressed through the reaction of allylsilances and aldehydes. This reaction will show the efficiency of the catalyst by producing its product with a desired, specific stereocenter. This catalyst would be able to affect the reaction greatly and still be regenerated since it is not directly influencing the reaction it aids. Having a diphosphorus compound that is negatively charged has been proven to be a better method to synthesize the desired palladium diphosphine dimer. This dimer compound is the only one known in which the ligands are unsymmetrical and not neutral. This gives the desired negative charge needed since it is known to be the better method of synthesis. Therefore, the focus is on unsymmetrical diphospine ligands that contain only aromatic substituents with different electronic and/or spatial character to further examine conditions that favor the diphosphine becoming negatively charged. Having completed 3 reactions out of the 5 necessary, we have produced a relatively pure product with a 26.5% yield. The next step of this reaction sequence is to increase the purity of the third reaction product as well as the percent yield.