Enantioselective Synthesis of 2,5-disubstitutedpolyhydroxy Pyrrolidines Mike Heffner, Derek Ross, and Owen Thomas

Abstract

Because enantiomers react with the body in different ways, it isimportant to pharmaceutical companies to have methods of producingenantiomerically pure substance. Because enantiomers are so similarin both their chemical and physical properties they are extremelydifficult to separate, often affording very low yields. Our researchuses an enantiomerically pure (~99.9%) starting material and thenmanipulates it in ways such that enantiopurity is maintained. Thisprocess eliminates the need to separate the enantiomers. Two mainmethods of reacting our starting material that add a great deal ofversatility are the Grubs Cross Metathesis and the Grignard Addition.The Grubs allows us to add on anything to the end of the double bondbefore cyclyzing and using the Grignard we are able to add on to thecyano group. Once the molecule cyclizes the groups added by thesereactions are positioned at 2 and 5 on the ring. This, along withthe two synthetic pathways, allows us access to functionalizing thepyrrole system, which is used in many drugs on the market today.