Dominic V Mcgrath

Dominic V Mcgrath

Professor, Chemistry and Biochemistry-Sci
Professor, BIO5 Institute
Primary Department
Department Affiliations
Contact
(520) 626-4690

Research Interest

Dominic Mcgrath, PhD, set forth a program which involves the use of organic synthesis for the design, development, and application of new concepts in macromolecular, supramolecular, and materials chemistry. Research efforts span a number of areas in the chemical sciences and include studies of: 1) chiral dendritic macromolecules and the effect of chiral subunits on dendrimer conformation, 2) photochromic dendrimers and linear polymers which undergo structural changes in response to visible light, 3) liquid crystalline materials based on dendritic and photochromic mesogens, and 4) synthesis of new ligands based on saturated nitrogen heterocycles.A continuing interest remains in the effect of structural perturbations on the properties and functional of dendritic macromolecules. Part of this research addresses the design, synthesis, and study of dendrimeric materials containing chiral moieties in the interior for influencing the conformational order of these 3-dimensional macromolecules. An ultimate goal is to develop materials active for the selective clathration of small guest molecules. Potential applications include chemical separations, sensor technology, environmental remediation, and asymmetric catalysis.Dr. Mcgrath and his lab team recently developed several new classes of dendritic materials containing photochromic subunits. As nature uses light energy to alter function in photoresponsive systems such as photosynthesis, vision, phototropism, and phototaxis, they use light energy to drive gross topological or constitutional changes in fundamentally new dendritic architectures with precisely placed photoresponsive subunits. In short, they can drive dendrimer properties with light stimuli. Two entirely new classes of photoresponsive dendritic macromolecules have been developed and include: 1) photochromic dendrimers and 2) photolabile dendrimers. Dr. Mcgrath anticipates that switchable and degradable dendrimers of this type will have application in small molecule transport systems based on their ability to reversibly encapsulate guest molecules. He continues to develop these materials as potential transport hosts and photoresponsive supramolecular assemblies.

Publications

McElhanon, J. R., & McGrath, D. V. (2000). Toward chiral polyhydroxylated dendrimers. Preparation and chiroptical properties. Journal of Organic Chemistry, 65(11), 3525-3529.

Abstract:

Four dendrimers (1b-4b) containing chiral vicinal diol-based subunits were prepared from their acetonide-protected precursors (1a-4a). The optical activity of these chiral dendritic structures was successfully modeled using structurally similar, low molecular weight model compounds. Using the [Φ](d) values of the low molecular weight model compounds 5b-7b, we calculated [Φ](d) values for dendrimers 1b-4b that agree to within 4.5% of the observed values. Agreement between the optical activity of the model compounds and that of the dendrimers leads to the conclusion that the conformational equilibria of the dendrimer subunits are not perturbed relative to those of the model compounds.

Kevwitch, R. M., Shanahan, C. S., & McGrath, D. V. (2012). Vanillin and o-vanillin oligomers as models for dendrimer disassembly. New Journal of Chemistry, 36(2), 492-505. doi:http://doi.org/10.1039/c1nj20841a

Abstract:

Linear analogs have been synthesized to model disassembling dendrimers. These linear analogs provide a facile synthesis to molecules that can be used to test new trigger groups and cleavage vectors. Vanillin and o-vanillin were used as the monomer units of these analogs and two trigger groups, allyl and o-nitrobenzyl, were chosen to test the disassembly process. Allyl triggered analogs 1a-d and 3a-d and o-nitrobenzyl triggered analogs 2a-c and 4a-c showed good to excellent disassembly as followed by the evolution of p-nitrophenoxide reporter ion by UV-Visible spectroscopy. The rate and yield of disassembly was shown to depend on experimental conditions as well as length of the cleavage vector. © 2012 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.

McGrath, D. V., Brabson, G. D., Sharpless, K. B., & Andrews, L. (1993). Reinvestigation of the infrared spectra of oxoosmium(VI) esters by isotopic labeling. Inorganic Chemistry, 32(19), 4164-4165.
Szalai, M. L., Sisk, D. T., Horst, M. J., & McGrath, D. V. (2008). Impact of click chemistry strategies on the synthesis of dendritic systems: Chromophore modification and disassembling systems. American Chemical Society, Polymer Preprints, Division of Polymer Chemistry, 49(1), 184-.
Warren, P. D., McGrath, D. V., & Vande Geest, J. P. (2010). Effect of Crosslinker Length and Composition on the Hydrophobicity and Thermomechanical Response of Acrylate-Based Shape-Memory Polymers. Macromolecular Materials and Engineering, 295(4), 386-396. doi:http://dx.doi.org/10.1002/mame.200900348