Dr. Tamara Hamilton
Welcome to the Hamilton Research Group at Barry University! Research in the group is performed entirely by undergraduates, who learn techniques including organic synthesis, solid-state chemistry, synthesis of air-sensitive materials, column chromatography, self-assembly, coordination chemistry, green chemistry, crystallization, NMR, UV/Vis spectroscopy, IR spectroscopy, and analysis of X-ray crystallographic data.
Our research program has two goals:
- Development of more environmentally benign syntheses of porphyrins using a solvent-free approach called mechanochemistry, where reagents are ground together using a mortar and pestle, or an automated ball mill.
- Using exo-dentate porphyrins as ligands in metal-organic assembly metal-organic polyhedra and evaluation of their efficacy as catalysts.
Solvent-free Synthesis of Porphyrins
Reaction scheme for the mechanochemical synthesis of porphyrins.
We combine an aldehyde with pyrrole in the presence of an acid catalyst and grind using a mortar and pestle. After a few minutes grinding, a pink crystalline powder forms. Presence of a porphyrin is confirmed by UV/Vis and 1H NMR spectroscopy. The mechanochemical process can also be automated using a ball-mill. We have shown that the approach works with a variety of aldehydes, giving yields similar to, or in some cases greater than, those available through traditional solution-based methods (Shy et al. Faraday Discuss. 2014, 170, 59-69). We are currently working on expanding the approach to include aldehydes with bulky R-groups, mixed-aldehyde syntheses, and synthesis of di-substituted porphyrins.
Pyrrole, an aldehyde, and an acid catalyst are combined in a mortar. The reactants are colorless liquids.
After c. 1 min grinding, a pink powder starts to form.
After c. 6 min grinding, the reaction mixture is completely transformed to a pink, crystalline product.
Current and Former Undergraduate Research Students
- Michaela Reyes, current student.
- Nirva Maxi, 2017
- Diana Cordero, 2017. Went on to graduate studies at MIT.
- Qiwen Su, 2017. Went on to research internship at Pacific Northwest National Laboratory.
- Suzely Alexis, 2016.
- Cindy Molina, 2016. Went on to veterinary school, Michigan State University.
- Shanika Kingston, 2016. Went on to work as a research associate at the College of Pharmacy at Midwestern University, Arizona.
- Taylor Sabol, 2015.
- Victoria Hoelscher, 2015. Went on to McGovern Medical School, Houston, Texas.
- Miriam Basden, 2014. Went on to be a Nursery Wildlife Rehabilitator, South Florida Wildlife Center.
- Hannah Shy, 2013.Went on to the University of Arizona College of Medicine.
- Deepa Gharbharan, 2013. MS Program Anesthesiology Assistant, Nova Southeastern University.
- Paula Mackin, 2013. MS Program Occupational Therapy, Western University, Ontario, Canada.
- Meghan Knol, 2012. Went on to University of Michigan Medical School.
- Elvis Camacho, 2011. Went on to Columbia University Neuroscience Program.
- Cherice Boyce, 2010. Went on to MS Program in Public Health, University of West Indies.
- Vanessa Narciso, 2010. Went on to DMD Program, Nova Southeastern University.
- Megan Barnes, 2010.
- Simon Astor, 2009. Went on to MD Program, Nova Southeastern University.
- Frantzesca Belancourt, 2009. Went on to MS Program in Biomedical Sciences, Larkin Health Sciences Institute.
- Andrea Orvieto, 2009.
- Our research was highlighted in Barry Magazine
- What is a porphyrin? Wikipedia entry
- The 12 Principles of Green Chemistry: EPA website
- Back to Dr. Hamilton's
Group members at Barry's STEM Symposium, 2016 (L to R) Nirva Maxi, Qiwen Su, Dr. Hamilton, Shanika Kingston, Diana Cordero, Victoria Hoelscher.