|Research in our group focuses on a range of challenges facing chemical synthesis. We have active research programs that draw upon and impact a number of areas, including:|
1) Total Synthesis of Natural Products
2) Medicinal Chemistry
3) Bioinorganic and Organometallic Catalysis
4) Materials Science
Central to each of these programs is our fascination with the biosynthesis of natural products and natural materials. To address challenges of synthetic efficiency, our group tries to adapt biosynthetic pathways to the laboratory setting, which often forces us to address fundamental challenges of catalysis and synthetic design. Solutions stemming from these investigations provide tools to address issues of synthetic efficiency, which is a particularly pressing challenge as society strives to reach a more sustainable future. In this context, our group has active interests in:1) Minimizing the environmental impact of chemical synthesis (i.e. â€œgreenâ€ or sustainable synthesis)
2) Identifying and exploiting sustainable sources of chemical feedstocks
Biomimetic Total Synthesis of Natural Products
Our group has a particular interest in complex cascade reactions, which efficiently create molecular complexity from relatively simple starting materials. To design these transformations, we draw upon biosynthetic pathways, which frequently exploit spring-loaded molecules to create multiple bonds via isomerization. Our current efforts are focused on a unified approach to the lignan family of polyphenols.
In general, functional molecules and materials contain a greater degree of C-O, C-N and C-S bonds than their precursors. As a result, the efficiency of chemical synthesis is intimately linked to the efficiency of C-H bond oxidation. Molecular oxygen is the ideal terminal oxidant for these transformations, as it represents a sustainable source of chemical potential energy that frequently produces water as the sole by-product. In order to activate O2, our group draws inspiration from metalloenzymes, and develops simplified mimics that recreate the enzymatic active site in the absence of the protein matrix.
Recent work in this area has focused on the dinuclear copper enzyme tyrosinase, which is responsible for the production of pigments in nearly all living organisms. Our catalyst design builds upon more than 50 years of efforts to mimic tyrosinase, and enables the first catalytic aerobic oxidation of phenols to ortho-quinones. We are currently pursuing a number of projects stemming from this initial success that span basic mechanism (organometallic and bioinorganic chemistry) as well as synthetic applications (organic synthesis).
Mechanochemical Synthesis of Single Molecule Magnets
Single molecule magnets are of relevance in the development of spintronic devices and have the potential to dramatically increase the storage density of digital information. Our group is focusing on a solvent free, mechanochemical synthesis of molecular magnets directly from low-valent metals and quinones. This work has spawned several projects aimed at bulk metal activation and corrosion, and couples solvothermal organic ligand synthesis with solid state metal-organic material synthesis.
(1) â€œControlling the Catalytic Aerobic Oxidation of Phenols.â€ Esguerra, K. V. N.; Fall, Y.; Petitjean, L. Lumb, J. P.* J. Am. Chem. Soc. 2014, 136, 7662.
(2) â€œA Biomimetic Catalytic Aerobic Functionalization of Phenols.â€ Esguerra, K. V. N.; Fall, Y.; Lumb, J. P.* Angew. Chem. Int. Ed. 2014, 53, 5877.