Dale Shellhammer

Dale Shellhammer

  • Professor Emeritus
  • Undergraduate Research Mentor
  • Phone: 619.849.2207

Education

  • Ph.D., Department of Chemistry (Organic), University of California, Santa Barbara, CA with Dr. Donald H. Aue
  • B.A., University of California at Irvine, Irvine, CA

Background

Education:

1969-73Ph.D., Department of Chemistry (Organic), University of California, Santa Barbara, CA with Dr. Donald H. Aue.

1965-69B.A., University of California at Irvine, Irvine, CA.

Employment:

1973 - presentProfessor, Department of Chemistry, Point Loma Nazarene University (PLNU)

1974 - presentDirector, Summer Undergraduate Research Program at PLNU

1989 - 95Research Chemist/Consultant, Alliance Pharmaceutical Corporation, San Diego, CA

Honors:

2013Outstanding Achievement Award, Sigma Xi

 

2004Co-organizer, Symposium on Analytical and Fluorine Chemistry, 228 th National Meeting of the American Chemical Society, August 24, 2004, Philadelphia, PA.

2003Nov. 2003. Served on the Chemistry Division Review Panel of the National Science Foundation. Reviewed proposals for Research Experience for Undergraduate (NSF-REU).

2000 - 2005

Scientific Advisory Board, Fluorotronics

1999Candidate for Vice Chair of the Fluorine Division of the American Chemical Society

1997 - 2000Member Executive Committee of the Fluorine Division of the American Chemical Society.

1989 - 1994Consultant, Alliance Pharmaceutical, San Diego, CA

1989 - 1990Chairman, Scientific Advisory Board, Alliance Pharmaceutical

Grants:

1973 - presentTotal of 20 research grants for over $900,000

2007 - 2009 National Science foundation Grant, Research and Undergraduate Institutions (NSF RUI) $124,980

2001 - Mossan Undergraduate Research Fellowship in Fluorine Chemistry

Membership:

1968 - presentAmerican Chemical Society

Research

 

CURRENT RESEARCH

Our present research studies are focused on the influence that vinyl fluorine atoms have on the reaction of isocyanates to form beata-lactams.  beta-lactams are found in some antibiotics and they show potential as cholesterol lowering drugs. Reaction of isocyanates with fluoroalkenes provide beta-lactams containing a fluorine atom.  Many new drugs and agricultural chemicals comming to market now contain a fluorine atom that facilitates the efficacy of the new drug.

AREAS OF RESEARCH

Dr. Shellhamer’s research focus is primarily on organofluorine chemistry.  Organofluorine molecules are an important class of compounds in medicinal chemistry.  There are a limited number of reactions available to the synthetic chemist for incorporating fluorine into organic molecules.  We have developed new reactions with xenon difluoride, investigated the synthetic parameters of dialkylaminosulfur trifluoride reagents, and studied the reactions of interhalogen electrophiles with monofluoroalkenes to describe the effect a fluorine atom has on the symmetry of halonium ion intermediates.   Dr. Shellhamer’s recent research is on the reaction of isocyanates with monofluoroalkenes.

Reactions with Isocyanates

We found that when the monofluoroalkenes react with chlorosulfonyl isocyanate, the reaction pathway changes to a concerted process.  These findings were used to enhance the synthetic utility of these reactions.
“Kinetic Studies on the Reaction of Chlorosulfonyl Isocyanate with Monofluoroalkenes: Experimental Evidence for Both Stepwise and Concerted Mechanisms and a Pre-equilibrium Complex on the Reaction Pathway”, Dale F. Shellhamer*, Summer A. Bunting, Kelli R. Hickle, Parker C. Horn, Jacob C. Milligan, Danielle E. Shipowick, Lincoln B. Smith, David J. Vandenbroek, Marc C. Perry, and Jerry A Boatz†, Journal of Organic Chemistry, 2013, 78, 246-252
“Reaction of chlorosulfonyl isocyanate with fluorosubstituted alkenes: Evidence for a concerted pathway” Shellhamer, Dale F.; Davenport*, Kevyn J.; Hassler*, Danielle M.; Hickle*, Kelli R.; Thorpe*, Jacob J.; Vandenbroek*, David J.; Heasley, Victor L.; Boatz, Jerry A.; Reingold, Arnold L. and Moore, Curtis E., Journal of Organic Chemistry, 2010, 75, 7913.


Reactions with Xenon Difluoride

We developed a photochemical reaction and alkoxyfluorination reactions with xenon difluoride. Published papers describing these studies include:

"A Mild Method for introducing iodine Monofluoride into Alkenes and Iodination of Aromatics Using Xenon Difluoride," D.F. Shellhamer, B.C. Jones, B.J. Pettus, T.L. Pettus, J.M. Stringer, V.L. Heasley. J. Fluor. Chem., 88, 37, 1998

"Addition Reactions of Electronegative Alkoxyxenon Fluorides with Alkenes," M. L. Druelinger, D. F. Shellhamer, R. D. Chapman, S. A. Shackelford, M. E. Reiner, S. L. Carter, R. P. Callahan and C. R. Youngstrom, Journal of the Chemical Society, London, Perkin Transactions 2, 787, 1997.

"The Fluorination of Cyclopentadiene and 3,4-Epoxycyclopentene," D. F. Shellhamer, M. C. Chiaco, K. M. Gallego, W. S. C. Low, B. Carter, V. L. Heasley, and R. D. Chapman, Journal of Fluorine Chemistry, 72, 83, 1995.

"Reaction of Alkylhypochlorites and Xenon Difluoride with Cyclohexene," D. F. Shellhamer, M. J. Horney, A. L. Toth and V. L. Heasley, Tetrahedron Letters, 33, 6903, 1992.

" The Regioselectivity in the Addition of Alkoxyxenon Fluorides," D. F. Shellhamer, S. L. Carter, R. H. Dunham, S. N. Graham, V. L. Heasley, R. D. Chapman and M. L. Druelinger, Journal of the Chemical Society, London, Perkin Transactions 2, 159, 1989 and references therein.

"Radical Additions of Xenon Difluoride to cis- and trans-1-Phenylpropenes: Comparison with Trichloroamine and Iodobenzene Dichloride," D. F. Shellhamer, M. L. Ragains, B. T. Gipe, V. L. Heasley and G. E. Heasley, The Journal of Fluorine Chemistry, 20, 13, 1982.

 

Dialkylaminosulfur Trifluoride Reagents

We investigated the stereochemistry of these reagents and their reactions with dialcohols and cyclopentadiene epoxide. Published papers include:

"Reaction of Aminosulfur Trifluorides with Alcohols: Inversion vs. Retention", D. F. Shellhamer, A. A. Briggs, B. M. Miller, J. M. Prince, D. H. Scott and V. L. Heasley, Journal of the Chemical Society, London, Perkin  Transactions 2, 973, 1996.

"Reaction of Diethylaminosulfur Trifluoride with Diols", D. F. Shellhamer, D. T. Anstine, K. M. Gallego, B. R. Ganesh, A. A. Hanson, K. A. Hanson, R. D. Henderson, J. M. Prince and V. L. Heasley, Journal of the Chemical Society, London, Perkin Transactions 2, 861, 1995.

"The Fluorination of Cyclopentadiene and Epoxycyclopentene", D. F. Shellhamer, M. C. Chiaco, K. M. Gallego, W. S. C. Low, B. Carter, V. L. Heasley and R. D. Chapman. Journal of Fluorine Chemistry, 72, 83, 1995.

"Facile Addition of Poorly Nucleophilic Alcohols to Unactivated Alkenes", D. F. Shellhamer, R. P. Callahan, M. L. Druelinger, R. D. Chapman, and V. L. Heasley. Synthesis, 1997, 9, 1056.

Interhalogen Fluorides

Some of our earlier work to generate interhalogen fluorides include:

“The Chemistry of Interhalogen Monofluorides,” Dale F. Shellhamer* and Victor L. Heasley, Advances in Organic Synthesis, 2006, Vol. 2, Bentham Science Publishers, p. 43.

“Symmetry of Chloronium Ions from Ionic Reactions of Chlorine, Chlorine Monofluoride Gas and Chlorine Monofluoride Complex with Terminal Alkenes,” D.F. Shellhamer, P.K. Titterington*, V.L. Heasley.  J. Fluorine Chem., 124, 17, 2003.

"Generating Interhalogen Fluorides under Mild Conditions: A Comparison of Sluggish and Reactive Interhalogen Fluorides," D.F. Shellhamer, M.J. Horney, B.J. Pettus, T.L. Pettus, J.M. Stringer, and V.L. Heasley. J. Org. Chem., 64, 1094, 1999.

"A Mild Method for introducing iodine Monofluoride into Alkenes and Iodination of Aromatics Using Xenon Difluoride," D.F. Shellhamer, B.C. Jones, B.J. Pettus, T.L. Pettus, J.M. Stringer, V.L. Heasley. J. Fluorine. Chem., 88, 37, 1998.

"Generating Interhalogen Fluorides," D. F. Shellhamer, B. C. Jones, B. J. Pettus, T. L. Pettus, J. M. Stringer, V. L. Heasley, Robert G. Syvret and John M. Dobrolsky, Jr. Oral presentation at The 13th Winter Fluorine Conference at St. Petersburg Beach, FL on January 23, 1997.

"Reaction of Alkylhypohalites and Xenon Difluoride with Cyclohexene," D. F. Shellhamer, M. J. Horney, A. L. Toth and V. L. Heasley, Tetrahedron Letters, 33, 6903, 1992.

Oral presentation: "A Mechanistic Study on the Generation of Interhalogen Fluorides: A Search for Reaction Intermediates," B.J. Pettus and D.F. Shellhamer. Presented by B.J. Pettus at the 1997 Southern California Undergraduate Research Conference in Chemistry and Biochemistry on April 26, 1997 at California State University, Northridge, CA.

Halonium Ion Symmetry

“Addition of Open-Ion Electrophiles to Monofluoroterminal Alkenes and Hydrocarbon Alkenes” D. F. Shellhamer, H. K. Forberg, M. P. Herrick, S. J. Rodriguez, S. Sanabria, N.N. Trager and V. L. Heasley, Trends in Organic Chemistry, 2008, in press.

“Rearrangement of 3-Membered 1,1,2-Trifluorobromonium and Iodonium Ions and Comparison of Trifluorochloronium to Fluorocarbenium Ions” D. F. Shellhamer, K. J. Davenport, H. K. Forberg, M. P. Herrick, R. N. Jones, S.J. Rodriguez, S. Sanabria, N.N. Trager, R. J. Weiss, V. L. Heasley and J. A. Boatz, J. Org. Chem. 2008, 73, 4532.

“Correlation of Calculated Halonium Ion Structures with Experimental Product Distributions from Terminal Alkenes: The Effect of Electron-Withdrawing Fluorine Substituents on the Structure and Charge Localization of Halonium Ions,” D.F. Shellhamer, D.C. Gleason*, V.L. Heasley, and J.J. Lehman.  Tetrahedron, 2006, 62, 11608.

“Ionic Reaction of Halogens with Terminal Alkenes: The Effect of Electron-Withdrawing Fluorine Substituents on the Bonding of Halonium Ions,” D.F. Shellhamer, J.L. Allen*, R.D. Allen*, D.C. Gleason*, C. O’Neil Schlosser*, B.J. Powers*, J.W. Probst*, M.C. Rhodes*, A.J. Ryan*, P.K. Titterington*, G.G. Vaughan* and V.L. Heasley.  J. Org. Chem., 68, 3932, 2003.

“Symmetry of Chloronium Ions from Ionic Reactions of Chlorine, Chlorine Monofluoride Gas and Chlorine Monofluoride Complex with Terminal Alkenes,” D.F. Shellhamer, P.K. Titterington*, V.L. Heasley.  J. Fluorine Chem., 124, 17, 2003.

“Comparison of the Electrophilic and Free-Radical and 1,3-Butadien,” D.F. Shellhamer, D.C. Gleason*, G.G. Vaughan*, A.J. Ryan*, P.K. Titterington*, V.L. Heasley and J.J. Lehman.  J. Fluorine Chem., 123, 171, 2003.

Publications

Patent:

“Detection of Carbon Halogen Bonds,” Gorelik, V.S.;  Sharts, C.M.; Sharts, O.N.; Metzger, R.P.; Shellhamer, D.F.; Wischnath, G.R., U.S. Patent No. US 7,433035 B2. Oct. 7, 2008.

Book Chapters: 

"The Chemistry of Interhalogen Monofluorides," Dale F. Shellhamer and Victor L. Heasley in Advances in Organic Synthesis, Vol. 2, 2006, pg. 43.  Bentham Science Publishers, The Netherlands.  ISBN: 90-77527-08-7.


"Is there a Time and Place for Raidopaque Fluorocarbons," D.M. Long, C.B. Higgins, R.F. Mattrey, R.M. Mitten, F.K. Multer, C.M. Sharts and D.F. Shellhamer in Preparation, Properties, and Industrial Applications of Organofluorine Compounds, 1982, pg. 139, Ellis Harwood Limited, England.  ISBN: 0-85312-276-8.

 

  

Five most recent professional publications out of 68 (#'s 1 & 2 are related to the new area of research):

  1. “Kinetic Studies on the Reaction of Chlorosulfonyl Isocyanate with Monofluoroalkenes: Experimental Evidence for Both Stepwise and Concerted Mechanisms and a Pre-equilibrium Complex on the Reaction Pathway”, Dale F. Shellhamer*, Summer A. Bunting, Kelli R. Hickle, Parker C. Horn, Jacob C. Milligan, Danielle E. Shipowick, Lincoln B. Smith, David J. Vandenbroek, Marc C. Perry, and Jerry A Boatz†, Journal of Organic Chemistry, 2013, 78, 246-252
  2. “Reaction of chlorosulfonyl isocyanate with fluorosubstituted alkenes: Evidence for a concerted pathway” Shellhamer, Dale F.; Davenport*, Kevyn J.; Hassler*, Danielle M.; Hickle*, Kelli R.; Thorpe*, Jacob J.; Vandenbroek*, David J.; Heasley, Victor L.; Boatz, Jerry A.; Reingold, Arnold L. and Moore, Curtis E., Journal of Organic Chemistry, 2010, 75, 7913.
  3. “Synthesis of a New Humic Acid Model, 2,4,6,6-Tetrachloro-2-methylcyclohex-4-ene-1,3-dione and Investigation of its Reactions with Monochloramine in Ether and in Methanol” Heasley, Victor L., Mitrovich, Kristin M., Sator Lisa C., Fisher, Audra M., Kerk, Amber R.E. and Shellhamer, Dale F., Research Journal of Chemistry and Environment, 2010, 14(4), 52.
  4. “Reaction of halogens and interhalogens with 1,1,2-trifluorobut-1-en-4-ol and 3-butene-1-ol: A study on the rearrangement of trifluorosubstituted 3-membered halonium ions” Shellhamer, Dale F.; Davenport*, Kevyn J.; Jones*, Rachel N.; Thorpe*, Jacob J.; Weiss*, Ryan J. and Heasley, Victor L., Trends in Organic Chemistry, 2010, 14, 73-76.
  5. “Addition of Open-Ion Electrophiles to Monofluoroterminal Alkenes and Hydrocarbon Alkenes” D. F. Shellhamer, H. K. Forberg, M. P. Herrick, S. J. Rodriguez, S. Sanabria, N.N. Trager and V. L. Heasley,  Trends in Organic Chemistry, 2008, 12, 39.

 

Five most recent presentations:

  1. Dale F. Shellhamer, Jacob C. Milligan, Danielle E. Shipowick, Lincoln B. Smith and Jerry A. Boatz, "Kinetic and Quantum Chemical Calculation Studies on the Stepwise vs. Concerted Pathways for Reaction of Chlorosulfonyl Isocyanate Reactions with Monofluoroalkenes", 21st Winter Fluorine Conference, St. Petersburg FL., January 13-18, 2013.
  2. Jacob C. Milligan, Danielle E. Shipowick and Dale F. Shellhamer “Synthetic Utility of CSI Reactions at Lower Temperatures”, 245th American Chemical Society National Meeting and Exposition, New Orleans, LA, April 7-11, 2013
  3. Summer A. Bunting and Dale F. Shellhamer, “Microwave initiation and N-heterocyclic carbene catalysis of chlorosulfonyl isocyanate reactions with unreactive hydrocarbons and fluoroalkenes”, 243rd American Chemical Society National Meeting and Exposition, San Diego, CA, March 25-29, 2012
  4. Parker, C. Horn and Dale F. Shellhamer, “Kinetics and studies on the reaction of chlorosulfonyl isocyanate with monofluoroalkenes”, 243rd American Chemical Society National Meeting and Exposition, San Diego, CA, March 25-29, 2012
  5. Dale F. Shellhamer*, Summer A. Bunting*, Parker C. Horn*, Jacob C Milligan*, Danielle E. Shipowick*, and Jerry A. Boatz§, “Calculations and experimental data supporting both concerted and stepwise pathways for reaction of chlorosulfonyl isocyanate with monofluoroalkenes”, 243rd American Chemical Society National Meeting and Exposition, San Diego, CA, March 25-29, 2012