Type of Document Dissertation Author Abrams, Jason Nathaniel URN etd-11042009-131626 Title 5-Endo-Dig Cyclization of a Carbon-Centered Radical and Utility of Cyclopentene Bromosulfone Product Degree Doctor of Philosophy Department Chemistry and Biochemistry, Department of Advisory Committee
Advisor Name Title Igor V. Alabugin Committee Chair Brian G. Miller Committee Member Gregory B. Dudley Committee Member William M. Landing University Representative Keywords
Date of Defense 2009-07-22 Availability unrestricted AbstractThe Baldwin rules provide a robust guideline for predicting the favorability of ring closure of
reactive intermediates based upon stereoelectronic considerations. Our group was intrigued by
the lack of examples of 5-endo-dig cyclizations with carbon-centered radicals, particularly
because these reactions were suggested to be favorable according to the Baldwin rules and to
our previous computational investigations using density functional analysis. We therefore set
out to fill the gap in the arsenal of radical C-C bond forming processes by using computational
data to design a new radical process. The first part of this thesis describes our studies aimed at
the discovery of the first efficient 5-endo-dig cyclization of a carbon-centered radical. This is
followed by experimental design and synthesis of substrates and finally reaction conditions
which yield products through this novel mode of cyclization.
The second part of this thesis explores the synthetic utility of the cyclized cyclopentene
bromosulfone products. First, background information for the preparation and utility of vinyl
sulfones is provided. This is followed by our results for derivatization of the bromide functional
group of our cyclopentene bromosulfone products.
Proper design of substrates and reaction conditions has allowed the 5-endo-dig radical
cyclizations to finally become an experimental reality after more than forty years since the
original prediction. The cyclized products which are enriched with functionality have been
transformed into a variety of other products, emphasizing the importance of this discovery.
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