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Associate Member, Materials Science Institute
B.S., Stanford University, 1978. M.S., Stanford University, 1979 (James P. Collman). Ph.D., California Institute of Technology, 1983 (Robert Grubbs). Postdoctoral: University of California, Los Angeles, 1983–85 (Donald J. Cram). Honors and Awards: Fannie and John Hertz Foundation Fellow, 1979–83; American Cancer Society Scholar, 1984–85. At Oregon since 1989.
Research Interests:
Research in the Doxsee group revolves around various aspects of molecular recognition phenomena. Through the design, synthesis, and exploitation of molecules that interact with each other or with metal ions, we address a number of fundamental topics, including the phase- and shape-selective assembly of solid-state materials from molecular precursors and the development of ion-selective binding agents. Through these ongoing research efforts as well as separate projects dedicated to the development of new pedagogical materials, we seek to train students in the concepts and practice of green chemistry.
Green Chemistry
Working with Professor Hutchison, Professor Doxsee has transformed the undergraduate
organic laboratory curriculum so that all students now learn the fundamentals
of organic chemistry within the context of green chemistry. Development
of new laboratory experiments that both teach important chemical concepts
and illustrate the principles of green chemistry is an ongoing activity
in the Doxsee laboratory. Our other research activities, outlined below,
also implicitly and explicitly address green chemical issues by focusing
on the development of selective reactions that employ safer reagents, and
are effected with significantly reduced energy costs.
Phase- and Shape-Selective Assembly of Solid-State
Materials
Simple organic and inorganic salts are often completely insoluble in non-polar
solvents. However, solutions of complexes of salts with crown ethers in
such solvents may be readily prepared. These solubilized salts undergo “metathesis”
reactions with other solubilized reactants, resulting in the crystallization
of solid-state materials. The unique solvation and complexation interactions
presented under these crystallization conditions leads to dramatic alteration
of crystal form. For example, crystallization of silver bromide from water
generally affords cubic or octahedral crystals, while crystallization from
nonaqueous solvents affords a solvent-dependent variety of more complex
crystal forms. Further control is frequently exhibited over solid-state
phase as well as crystal form. Through use of small-molecule (or ion) precursors
under ambient conditions, we routinely access metastable phases. For example,
whereas crystallization of calcium carbonate from water affords the thermodynamic
phase (calcite); crystallization from methanol solution affords a metastable
phase (vaterite). Adaptation of these procedures for the preparation of
binary and ternary metal oxides (e.g., WO3, MnWO4) frequently affords new
metastable phases. We are applying these crystallization approaches to problems
of current technological importance, particularly in the areas of optical
and electronic materials.
Ion-Selective Binding Agents
Many pharmacologically active drugs, including anti-inflammatories and antitumor
agents, bear the alpha-hydroxyketone functionality. Our studies, which we
hope will lead to development of ion-selective sensors and a better understanding
of the chemistry of these drugs in vivo, suggest this functionality is quite
effective at complexation of the biochemically ubiquitous calcium ion. We
have structurally characterized phenacyl alcohol, cortisone, and hydrocortisone
complexes of calcium and have quantified the details of their interaction
in solution with calcium and other group 2 metal ions. Related studies with
hydroxamic acids, tetracycline, and the antitumor agent adriamycin are planned.
These investigations, which are primarily analytical and structural in nature,
are complemented by our program of design and synthesis of efficient and
selective complexation agents for calcium. The latter studies include the
synthesis of colorimetric binding agents for calcium, designed to allow
simple and quantitative determination of calcium levels in biological fluids.
Selected Publications:
Doxsee, K. M. "Crystallization of solid-state materials via decomplexation of soluble complexes", Chemistry of Materials 1998, 10, 2610-2618.
Hanawalt, E. M.; Doxsee, K. M.; Weakley, T. J. R. "Reactions of tungsten pentacarbonyl and mercuric chloride complexes of 1,3,4-triphenyl-1,2-dihydrophosphete"; Heteroatom Chemistry 1998, 9, 21-28.
Doxsee, K. M.; Chang, R. C.; Chen, E.; Myerson, A. S.; Huang, D. "Crystallization of solid-state materials in nonaqueous gels. I. Silver bromide"; J. Am. Chem. Soc. 1998, 120, 585-586.
Doxsee, K. M.; Wierman, H. R. "Crystallization of salts of organic acids from non-conventional solvents"; Molecular Crystals and Liquid Crystals 1998, 313, 285-292.
Doxsee, K. M.; Juliette, J. J. J.; Nieckarz, G.; Zientara, K.; "Methane elimination and the formation of titanacycles: High regioselectivity in intramolecular C-H activation reactions of titanocene complexes", J. Am. Chem. Soc. 1994, 116, 2147-2148.
To Contact Dr. Doxsee:
Phone: 541-346-4628
doxsee@uoregon.edu
WEBMASTER
chem@uoregon.edu
