Type of Document Dissertation Author Phillips, Janice Paige URN etd-102498-111245 Title Rearrangements of Radical Anions Generated from Cyclopropyl Ketones Degree PhD Department Chemistry Advisory Committee
Advisor Name Title Tanko, James M. Committee Chair Anderson, Mark R. Committee Member Brewer, Karen J. Committee Member Castagnoli, Neal Jr. Committee Member Gibson, Harry W. Committee Member Wolfe, James F. Committee Member Keywords
- Marcus theory
- Homogeneous catalysis
- Reaction mechanism and kinetics
- Cyclopropyl ketones
- Cathodic reduction
- Ring opening
- Radical anion
Date of Defense 1998-05-04 Availability restricted AbstractCyclopropyl-containing substrates have been
frequently utilized as "probes" for the detection
of SET pathways in organic and biorganic systems.
These reactions are based on the
cyclorpropylcarbinyl - homoallyl rearrangement,
which is fast and essentially irreversible.
The implicit assumption in such studies is that if
a "radical" species is produced, it will undergo
ring opening. We have found that there are two
important factors to consider in the design of
SET probes: 1) ring strain, the thermodynamic
driving force for the rearrangement, and
2) resonance energy, which may help or hinder
rearrangement, depending on the specific system.
Delocalization of spin and charge were found to
be important factors pertaining to substituent
effects on the rates of radical anion
Previous studies from our lab have
centered on highly conjugated phenyl
cyclopropyl ketones. This work considers a series
of compounds varying in their conjugative
components from a highly conjugated
spiro[2.5]octa-4,7-dien-6-one and derivatives to
simple aliphatic ketones. Utilizing cyclic,
linear sweep voltammetry, and preparative
electrolysis techniques, it was discovered that
all substrates yielded ring opened products with
rates and selectivities that will prove useful
and informative in the design of mechanistic
probes based on the cyclorpropylcarbinyl -
homoallyl rearrangement. Rates of homogeneous
electron transfer from a series of hydrocarbon
mediators to substrates were measured using
homogeneous catalysis techniques. Standard
reduction potentials and reorganization energies
of substrates were derived using Marcus theory.
Conjugative interactions with the cyclopropyl
group are discussed.
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