Dr. Daniel Predecki
Associate Professor of Organic Chemistry
Organic chemistry is the study of molecules that contain carbon. Career opportunities in organic chemistry include drug discovery and development, agricultural chemicals, polymers, and textiles. My research has spanned many aspects of organic chemistry including kinetics, biochemistry, synthesis and forensics.
In 2015, 12.5 million people had misused prescription opioids and 33,091 people died from an opioid overdose (source: U.S. Dept. of Health and Human Services). During the Spring 2015 semester I completed a sabbatical (leave for research) at the Cumberland County Forensic Laboratory. I spent my sabbatical developing methods of analysis for six opioid drugs: codeine, morphine, hydrocodone, hydromorphone, oxycodone, and oxymorphone. This included procedures for derivatization and extraction of opioid samples from blood bank blood followed by analysis methods using gas chromatography-mass spectrometry. I was able to consistently analyze for 25 nanograms (and above) of codeine, morphine, hydrocodone, hydromorphone, oxymorphone, and oxycodone in 2 milliliters of blood bank blood.
In 2012, I published a kinetic study of two imines, N-methylisobutylidene (1) and N-isopropylethylidene (2) (Figure 1) that displayed previously unobserved non-first order kinetic behavior under acidic conditions.
Figure 1: Imines
The non-first order decay (figure 2) was attributed to a rapid approach to equilibrium, Keq, relative to Ka and k± (Figure 3). Direct measurement of the decay of the protonated imines, (1) and (2) resulted in calculation of the microscopic rate constants k1, k-1, Ka, and k±.
Figure 2: Example of a non-first order decay curve with two phases.
In general, protonated imineshave shown first order, single exponential decay kinetics under acidic conditions. Single exponential decay curves are observed if there is no build-up of intermediates (Figure 3, T+ and T±). This means Keq is slow relative to the rate limiting step (rls), k± (Figure 3). However, in this case, a biphasic decay curve was observed under acidic conditions (Figure 2), which was attributed to a buildup of intermediates and a change in rate limiting step from Keq to k±, under acidic conditions (Figure 3).
Figure 3: Imine Hydrolysis under Acidic Conditions (where R1 and R2 are carbon chains)
The imines we are studying do not have any biological relevance; however, there are imine type compounds that are formed in enzymatic pathways and therefore this work could be used as a model. This work is ongoing in my laboratory.
- Sirovetz, B.J.; Walters, N.E.; Bender, C.N.; Lenivy, C.M.; Troupe, A.S.; Predecki, D.P.; Richardson, J.N.; Zaleski, C.M. “A Multiweek Upper-Division Inorganic Laboratory Based on Metallacrowns.” J. Chem. Educ., 2013, 90(6), 782-785.
- Predecki, D. P. “Non-steady state intermediates: a re-examination of the kinetics of hydrolysis of N-methylisobutylidene and N-isopropylethylidene under acidic conditions.” Tetrahedron Lett., 2012, 53, 6250-6253.
- Mohler, D. L.; Coonce, J.G.; Predecki, D.P.; “Photoinduced DNA Cleavage by Benzenediradical Equivalents: 1,3- and 1,4-Bis(dicarbonylcyclopentadienyliron) benzene.” Bio. Org. Med. Chem. Lett. 2003, 17, 1377-1379.
- Peterson, L. A.; Predecki, D. P.; Thomson, N. M.; Villalta, P. W.; Donaldson, E. E. “Nucleophilic Reactions between Thiols and a Tobacco Specific Nitrosamine Metabolite, 4-Hydroxy-1-(3-pyridyl)-1-butanone.” Chem. Res. Toxicol. 2003, 16, 661-667.
- Byrns, M.C.; Predecki, D.P.; Peterson L.A. “Characterization of Nucleoside Adducts of cis-2-Butene-1,4-dial, a Reactive Metabolite of Furan.” Chem. Res. Toxicol. 2002, 15, 373-379.
- Peterson, L.A.; Naruko, K.C.; Predecki, D.P.; “A Reactive Metabolite of Furan, cis-2-Butene-1,4-dial, is Mutagenic in the Ames Assay.” Chem. Res. Toxicol. 2000, 13, 531-534.
Current Research Students
- Samantha Brayton
- Heritage Hamp
- Jessica Zheng
Former Research Students
- Erin Divito - Ph.D. from Duquesne - Works at PPG
- Chelsie Smith - Works at Wyeth Pharmaceuticals
- Joe DePasquale - Ph.D. from Drexel - Instructor at Northeastern University
- Dustin Underkoffler - Works at Johnson and Johnson
- Phillip Picket - M.S. from Bucknell - Accepted into Ph.D. program in polymer chemistry at the University of Southern Mississippi
- Diane Dietrich - Working on a Ph.D. in chemistry at Drexel University
- Katelyn Chadwick - Chemistry teacher at Freedom High School
- Todd Vargson - M.S. from the University of Pittsburgh - Works at PPG
- Shawn Spuhler - Works at the Pennsylvania Department of Environmental Protection
- Cassie Sidone - Works at Lakeview Health
- Mike Turley - Applying to medical school
- Heather Rensch - M.S. from Bucknell - Works at Bimax, Inc.
- Tyler Davidson - Accepted into the Ph.D. program in forensics at the University of West Virginia
- Josh Wolfgang - Accepted into the Ph.D. program in polymer chemistry at Virginia Tech
- Caleb Ancharski - accepted into optometry school
- Brandon Hockenberry - accepted into pharmacy school at Shenandoah University
- Charlie Waters - Accepted into the Ph.D. program in organic chemistry at the University of Maryland Baltimore County
My hobbies are powerlifting, fantasy football, spending time with my family, and "enlightening" students about the field of organic chemistry.
The chemistry majors awarded me "Most Likely to Tell a Dad Joke" in 2017, "Most Likely to Be in Their Office" in 2018, and I was awarded "Faculty of the Year" by the Shippensburg University Student-Athlete Advisory Committee in 2019.