Date of Award
© 2015 Peter A. Amadeo. All rights reserved. This work is freely available courtesy of the author. It may only be used for non-commercial, educational, and research purposes. For all other uses, including reproduction and distribution, please contact the copyright holder.
Bachelor of Arts
Chemistry & Biochemistry
Robert S. Paley
In the past, Paley lab has focused on the diastereoselective synthesis of spiroketals using sulfinyl iron(0) tricarbonyl diene complexes. This research has extended to study the formation of bis-spiroketals. As valuable natural products, bis-spiroketals are important synthesis targets, and the stereochemistry at the anomeric carbons is especially important. This research focuses on how sulfinyl iron(0) tricarbonyl diene complexes can help control the stereoselectivity of bis-spiroketal formation. The first attempt to make the desired bis-spiroketal involved preparmg a dihydroxy diketone precursor, which would undergo dehydrative cyclization. Unfortunately, there were various obstacles to preparing the precursor. Attempts to oxidize double bonds, remove dithiane protecting groups, and form the sulfinyl diene failed. Due to the many obstacles, a new synthesis was devised involving a gold catalyst. This course of action required the coupling of a hemi-acetal with an alkyne, so the hope was that the alkyne would be more stable and easier to work with than the dihydroxy diketone. Unfortunately, attempts to form the iron(0) tricarbonyl complex with the diene did not work when the diene also had an alkyne. When the complex was formed prior to the addition of the alkyne, nucleophilic addition of the alkyne failed. However, this complex was applied to the original synthesis to create the dihydroxy diketone precursor. While the final product was never synthesized, the most recent discovery is close. Following a simple oxidation of an alcohol and hydrogenation of an alkene, the original precursor should be ready to undergo dehydrative cyclization.
Amadeo, Peter A. , '15, "A Diastereoselective Approach to Bis-spiroketal Synthesis Using Sulfinyl Iron(0) Tricarbonyl Diene Complexes" (2015). Senior Theses, Projects, and Awards. 218.